BACKGROUND:By the way, from Wikipedia via google images, here is the superior frontal gyrus:
Previous functional magnetic resonance imaging studies have shown strong correlations between cue-elicited craving for cigarettes and activation of the superior frontal gyrus (SFG). Repetitive transcranial magnetic stimulation (rTMS) offers a noninvasive means to reversibly affect brain cortical activity, which can be applied to testing hypotheses about the causal role of SFG in modulating craving.
METHODS:
Fifteen volunteer smokers were recruited to investigate the effects of rTMS on subjective responses to smoking versus neutral cues and to controlled presentations of cigarette smoke. On different days, participants were exposed to three conditions: 1) high-frequency (10 Hz) rTMS directed at the SFG; 2) low-frequency (1 Hz) rTMS directed at the SFG; and 3) low-frequency (1 Hz) rTMS directed at the motor cortex (control condition).
RESULTS:
Craving ratings in response to smoking versus neutral cues were differentially affected by the 10-Hz versus 1-Hz SFG condition. Craving after smoking cue presentations was elevated in the 10-Hz SFG condition, whereas craving after neutral cue presentations was reduced. Upon smoking in the 10-Hz SFG condition, ratings of immediate craving reduction as well as the intensity of interoceptive airway sensations were also attenuated.
CONCLUSIONS:
These results support the view that the SFG plays a role in modulating craving reactivity; moreover, the results suggest that the SFG plays a role in both excitatory and inhibitory influences on craving, consistent with prior research demonstrating the role of the prefrontal cortex in the elicitation as well as inhibition of drug-seeking behaviors.
This blog reports new ideas and work on mind, brain, behavior, psychology, and politics - as well as random curious stuff. (Try the Dynamic Views at top of right column.)
Wednesday, July 27, 2011
Inappropriate cravings? Hold a magnet by your head!
Here's an idea for a BioTech startup!...(I'm not serious)...suggested by an article from McClemon et al. titled "Repetitive Transcranial Magnetic Stimulation of the Superior Frontal Gyrus Modulates Craving for Cigarettes."
Tuesday, July 26, 2011
Watching Humor in the Brain
Bekinschtein et al. look at what may be the brain correlates of "humor as a cognitive cleanup mechanism" mentioned in my June 17 post, at least in the case of jokes that depend on semantic ambiguity resolution:
What makes us laugh? One crucial component of many jokes is the disambiguation of words with multiple meanings. In this functional MRI study of normal participants, the neural mechanisms that underlie our experience of getting a joke that depends on the resolution of semantically ambiguous words were explored. Jokes that contained ambiguous words were compared with sentences that contained ambiguous words but were not funny, as well as to matched verbal jokes that did not depend on semantic ambiguity. The results confirm that both the left inferior temporal gyrus and left inferior frontal gyrus are involved in processing the semantic aspects of language comprehension, while a more widespread network that includes both of these regions and the temporoparietal junction bilaterally is involved in processing humorous verbal jokes when compared with matched nonhumorous material. In addition, hearing jokes was associated with increased activity in a network of subcortical regions, including the amygdala, the ventral striatum, and the midbrain, that have been implicated in experiencing positive reward. Moreover, activity in these regions correlated with the subjective ratings of funniness of the presented material. These results allow a more precise account of how the neural and cognitive processes that are involved in ambiguity resolution contribute to the appreciation of jokes that depend on semantic ambiguity.
Monday, July 25, 2011
Confabulation
Here is an entry from Fiery Cushman on the Edge.org question "What scientific concept would improve everybody's cognitive toolkit?," on how we frequently rationalize our behavior, unaware of unconscious factors that actually guided it. Here are some clips:
We are shockingly ignorant of the causes of our own behavior. The explanations that we provide are sometimes wholly fabricated, and certainly never complete. Yet, that is not how it feels. Instead it feels like we know exactly what we're doing and why. This is confabulation: Guessing at plausible explanations for our behavior, and then regarding those guesses as introspective certainties…The problem is that we get all of our explanations partly right, correctly identifying the conscious and deliberate causes of our behavior. Unfortunately, we mistake "party right" for "completely right", and thereby fail to recognize the equal influence of the unconscious, or to guard against it.
People make harsher moral judgments in foul-smelling rooms, reflecting the role of disgust as a moral emotion. Women are less likely to call their fathers (but equally likely to call their mothers) during the fertile phase of their menstrual cycle, reflecting a means of incest avoidance. Students indicate greater political conservatism when polled near a hand-sanitizing station during a flu epidemic, reflecting the influence of a threatening environment on ideology. They also indicate a closer bond to their mother when holding hot coffee versus iced coffee, reflecting the metaphor of a "warm" relationship.
Automatic behaviors can be remarkably organized, and even goal-driven. For example, research shows that people tend to cheat just as much as they can without realizing that they are cheating. This is a remarkable phenomenon: Part of you is deciding how much to cheat, calibrated at just the level that keeps another part of you from realizing it.
One of the ways that people pull off this trick is with innocent confabulations: When self-grading an exam, students think, "Oh, I was going to circle e, I really knew that answer!" This isn't a lie, any more than it's a lie to say you have always loved your mother (latte in hand), but don't have time to call your dad during this busy time of the month. These are just incomplete explanations, confabulations that reflect our conscious thoughts while ignoring the unconscious ones.
Perhaps you have noticed that people have an easier time sniffing out unseemly motivations for other's behavior than recognizing the same motivations for their own behavior…we jump to the conclusion that others' behaviors reflect their bad motives and poor judgment, attributing conscious choice to behaviors that may have been influenced unconsciously… we assume that our own choices were guided solely by the conscious explanations that we conjure, and reject or ignore the possibility of our own unconscious biases...By understanding confabulation we can begin to remedy both faults.
Friday, July 22, 2011
The importance of our brains’ resting state activity.
Pizoli et al find, in an open access article describing the clinical case of a young boy with epileptic encephalopathy who underwent successful corpus callosotomy surgery for treatment of drop seizures (i.e., separation of connections between the two hemispheres), that resting state brain activity (temporal synchrony across distributed brain regions termed resting-state networks that persists during waking, sleep, and anesthesia) is required for normal brain development and maintenance:
One of the most intriguing recent discoveries concerning brain function is that intrinsic neuronal activity manifests as spontaneous fluctuations of the blood oxygen level–dependent (BOLD) functional MRI signal. These BOLD fluctuations exhibit temporal synchrony within widely distributed brain regions known as resting-state networks. Resting-state networks are present in the waking state, during sleep, and under general anesthesia, suggesting that spontaneous neuronal activity plays a fundamental role in brain function. Despite its ubiquitous presence, the physiological role of correlated, spontaneous neuronal activity remains poorly understood. One hypothesis is that this activity is critical for the development of synaptic connections and maintenance of synaptic homeostasis. We had a unique opportunity to test this hypothesis in a 5-y-old boy with severe epileptic encephalopathy. The child developed marked neurologic dysfunction in association with a seizure disorder, resulting in a 1-y period of behavioral regression and progressive loss of developmental milestones. His EEG showed a markedly abnormal pattern of high-amplitude, disorganized slow activity with frequent generalized and multifocal epileptiform discharges. Resting-state functional connectivity MRI showed reduced BOLD fluctuations and a pervasive lack of normal connectivity. The child underwent successful corpus callosotomy surgery for treatment of drop seizures. Postoperatively, the patient's behavior returned to baseline, and he resumed development of new skills. The waking EEG revealed a normal background, and functional connectivity MRI demonstrated restoration of functional connectivity architecture. These results provide evidence that intrinsic, coherent neuronal signaling may be essential to the development and maintenance of the brain's functional organization.
Thursday, July 21, 2011
Pressure to conform - survey of tight and loose cultures.
Gelfand et al. have constructed a metric they term "tightness-looseness" - the extent to which societies impose social norms, and have collected data across 33 large-scale cultures from ~7,000 individuals. Their questionnaire asked people to rate the appropriateness of 12 behaviors (such as eating or crying) in 15 situations (such as being in a bank or at a party). Then, they compared the responses to an array of ecological and historical factors. From Norenzayan's summary:
...Overall, they found that societies exposed to contemporary or historical threats, such as territorial conflict, resource scarcity, or exposure to high levels of pathogens, more strictly regulate social behavior and punish deviance. These societies are also more likely to have evolved institutions that strictly regulate social norms. At the psychological level, individuals in tightly regulated societies report higher levels of self-monitoring, more intolerant attitudes toward outsiders, and paying stricter attention to time. In this multilevel analysis, ecological, historical, institutional, and psychological variables comprise a loosely integrated system that defines a culture.
These findings complement a growing literature that reveals the power of the comparative approach in explaining critically important features of human behavior. For example, research suggests that the substantial variation in religious involvement among nations can be explained, in large part, by perceived levels of security. Religion thrives when existential threats to human security, such as war or natural disaster, are rampant, and declines considerably in societies with high levels of economic development, low income inequality and infant mortality, and greater access to social safety nets.
Blog Categories:
culture/politics,
human evolution,
social cognition
Wednesday, July 20, 2011
The Forbidden Fruit Intuition - our inability to cope with what we know about our minds.
I've recently done a scan of old MindBlog posts, and a number of them stand out so strongly for me, that I want to have their ideas repeated, hoping repetition will aid intellectual assimilation. Here then, a post from April 2006 on Thomas Metzinger's brief essay titled "The Forbidden Fruit Intuition", in the initial post I didn't point to his first paragraph,
I get frustrated when I try to reconcile what I know from empirical data to be true about my self (see the "I-Illusion" essay on this website) with the common sense feeling of agency and responsibility that we are share.
Our commonsense conceptions of ourselves have co-evolved over hundreds of thousands of years, along with their physiological, homeostatic, neuroendocrine, and limbic emotional correlates. This whole complex (us, that is) can be upset by facing what it can come to know to be true about the impersonal physical processes that actually run our show, finding it impossible to integrate its 'illusory' self image.
Here is a clip, and then its more extended context from the piece by Metzinger on edge.org..his response to the question "What is your dangerous idea." He frames it much better than I can. First the clip:
"I think that the irritation and deep sense of resentment surrounding public debates on the freedom of the will actually has nothing much to do with the actual options on the table. It has to do with the perfectly sensible intuition that our presently obvious answer will not only be emotionally disturbing, but ultimately impossible to integrate into our conscious self-models."
Then the more extended quotation:
"For middle-sized objects at 37° like the human brain and the human body, determinism is obviously true. The next state of the physical universe is always determined by the previous state. And given a certain brain-state plus an environment you could never have acted otherwise. A surprisingly large majority of experts in the free-will debate today accept this obvious fact...."
"Yes, you are a physically determined system. But this is not a big problem, because, under certain conditions, we may still continue to say that you are "free": all that matters is that your actions are caused by the right kinds of brain processes and that they originate in you. A physically determined system can well be sensitive to reasons and to rational arguments, to moral considerations, to questions of value and ethics, as long as all of this is appropriately wired into its brain. You can be rational, and you can be moral, as long as your brain is physically determined in the right way. You like this basic idea: physical determinism is compatible with being a free agent. You endorse a materialist philosophy of freedom as well. An intellectually honest person open to empirical data, you simply believe that something along these lines must be true.
Now you try to feel that it is true. You try to consciously experience the fact that at any given moment of your life, you could not have acted otherwise. You try to experience the fact that even your thoughts, however rational and moral, are predetermined — by something unconscious, by something you can not see. And in doing so, you start fooling around with the conscious self-model Mother Nature evolved for you with so much care and precision over millions of years: You are scratching at the user-surface of your own brain, tweaking the mouse-pointer, introspectively trying to penetrate into the operating system, attempting to make the invisible visible. You are challenging the integrity of your phenomenal self by trying to integrate your new beliefs, the neuroscientific image of man, with your most intimate, inner way of experiencing yourself. How does it feel?
I think that the irritation and deep sense of resentment surrounding public debates on the freedom of the will actually has nothing much to do with the actual options on the table. It has to do with the perfectly sensible intuition that our presently obvious answer will not only be emotionally disturbing, but ultimately impossible to integrate into our conscious self-models.
Or our societies: The robust conscious experience of free will also is a social institution, because the attribution of accountability, responsibility, etc. are the decisive building blocks for modern, open societies. And the currently obvious answer might be interpreted by many as having clearly anti-democratic implications: Making a complex society work implies controlling the behavior of millions of people; if individual human beings can control their own behavior to a much lesser degree than we have thought in the past, if bottom-up doesn't work, then it becomes tempting to control it top-down, by the state. And this is the second way in which enlightenment could devour its own children. Yes, free will truly is a dangerous question, but for different reasons than most people think. "
We all would like to believe that, ultimately, intellectual honesty is not only an expression of, but also good for your mental health. My dangerous question is if one can be intellectually honest about the issue of free will and preserve one's mental health at the same time. Behind this question lies what I call the "Forbidden Fruit Intuition": Is there a set of questions which are dangerous not on grounds of ideology or political correctness, but because the most obvious answers to them could ultimately make our conscious self-models disintegrate? Can one really believe in determinism without going insane?Here is the original post:
I get frustrated when I try to reconcile what I know from empirical data to be true about my self (see the "I-Illusion" essay on this website) with the common sense feeling of agency and responsibility that we are share.
Our commonsense conceptions of ourselves have co-evolved over hundreds of thousands of years, along with their physiological, homeostatic, neuroendocrine, and limbic emotional correlates. This whole complex (us, that is) can be upset by facing what it can come to know to be true about the impersonal physical processes that actually run our show, finding it impossible to integrate its 'illusory' self image.
Here is a clip, and then its more extended context from the piece by Metzinger on edge.org..his response to the question "What is your dangerous idea." He frames it much better than I can. First the clip:
"I think that the irritation and deep sense of resentment surrounding public debates on the freedom of the will actually has nothing much to do with the actual options on the table. It has to do with the perfectly sensible intuition that our presently obvious answer will not only be emotionally disturbing, but ultimately impossible to integrate into our conscious self-models."
Then the more extended quotation:
"For middle-sized objects at 37° like the human brain and the human body, determinism is obviously true. The next state of the physical universe is always determined by the previous state. And given a certain brain-state plus an environment you could never have acted otherwise. A surprisingly large majority of experts in the free-will debate today accept this obvious fact...."
"Yes, you are a physically determined system. But this is not a big problem, because, under certain conditions, we may still continue to say that you are "free": all that matters is that your actions are caused by the right kinds of brain processes and that they originate in you. A physically determined system can well be sensitive to reasons and to rational arguments, to moral considerations, to questions of value and ethics, as long as all of this is appropriately wired into its brain. You can be rational, and you can be moral, as long as your brain is physically determined in the right way. You like this basic idea: physical determinism is compatible with being a free agent. You endorse a materialist philosophy of freedom as well. An intellectually honest person open to empirical data, you simply believe that something along these lines must be true.
Now you try to feel that it is true. You try to consciously experience the fact that at any given moment of your life, you could not have acted otherwise. You try to experience the fact that even your thoughts, however rational and moral, are predetermined — by something unconscious, by something you can not see. And in doing so, you start fooling around with the conscious self-model Mother Nature evolved for you with so much care and precision over millions of years: You are scratching at the user-surface of your own brain, tweaking the mouse-pointer, introspectively trying to penetrate into the operating system, attempting to make the invisible visible. You are challenging the integrity of your phenomenal self by trying to integrate your new beliefs, the neuroscientific image of man, with your most intimate, inner way of experiencing yourself. How does it feel?
I think that the irritation and deep sense of resentment surrounding public debates on the freedom of the will actually has nothing much to do with the actual options on the table. It has to do with the perfectly sensible intuition that our presently obvious answer will not only be emotionally disturbing, but ultimately impossible to integrate into our conscious self-models.
Or our societies: The robust conscious experience of free will also is a social institution, because the attribution of accountability, responsibility, etc. are the decisive building blocks for modern, open societies. And the currently obvious answer might be interpreted by many as having clearly anti-democratic implications: Making a complex society work implies controlling the behavior of millions of people; if individual human beings can control their own behavior to a much lesser degree than we have thought in the past, if bottom-up doesn't work, then it becomes tempting to control it top-down, by the state. And this is the second way in which enlightenment could devour its own children. Yes, free will truly is a dangerous question, but for different reasons than most people think. "
Blog Categories:
culture/politics,
evolutionary psychology,
human evolution,
psychology,
self,
self help
Tuesday, July 19, 2011
Clips: Animal Joys - Diet and Weight
There's a fun article in today's NYTimes Science section ("The Joy of a Sun Bath, a Snuggle, a Bite of Pâté") reviewing a new book by animal behaviorist Jonathan Balcombe on "hedonic ethology" titled “The Exultant Ark.”
Also, one of the best articles on diet and weight loss, by Jean Brodie, that I've recently seen.
Also, one of the best articles on diet and weight loss, by Jean Brodie, that I've recently seen.
Our Umwelt
I found the following bit to be an engaging and refreshing reminder, from David Eagleman:
In 1909, the biologist Jakob von Uexküll introduced the concept of the umwelt. He wanted a word to express a simple (but often overlooked) observation: different animals in the same ecosystem pick up on different environmental signals. In the blind and deaf world of the tick, the important signals are temperature and the odor of butyric acid. For the black ghost knifefish, it's electrical fields. For the echolocating bat, it's air-compression waves. The small subset of the world that an animal is able to detect is its umwelt. The bigger reality, whatever that might mean, is called the umgebung.
The interesting part is that each organism presumably assumes its umwelt to be the entire objective reality "out there." Why would any of us stop to think that there is more beyond what we can sense?…it rarely strikes us that things could be different. Similarly, until a child learns in school that honeybees enjoy ultraviolet signals and rattlesnakes employ infrared, it does not strike her that plenty of information is riding on channels to which we have no natural access. From my informal surveys, it is very uncommon knowledge that the part of the electromagnetic spectrum that is visible to us is less than a ten-trillionth of it.
Our brains are tuned to detect a shockingly small fraction of the surrounding reality. Our sensorium is enough to get by in our ecosystem, but is does not approximate the larger picture...I think it would be useful if the concept of the umwelt were embedded in the public lexicon. It neatly captures the idea of limited knowledge, of unobtainable information, and of unimagined possibilities. Consider the criticisms of policy, the assertions of dogma, the declarations of fact that you hear every day — and just imagine if all of these could be infused with the proper intellectual humility that comes from appreciating the amount unseen.
Blog Categories:
attention/perception,
culture/politics
Monday, July 18, 2011
Peer pressure influences our memories
Fascinating observations from Edelson et al., who examine how our accurate initial memories of an event can be be changed by hearing different accounts from others. They find that activity in the hippocampus and amygdala brain regions involved in memory can vary, depending on how our memory has been shaped by interacting with others. Here is their abstract:
Human memory is strikingly susceptible to social influences, yet we know little about the underlying mechanisms. We examined how socially induced memory errors are generated in the brain by studying the memory of individuals exposed to recollections of others. Participants exhibited a strong tendency to conform to erroneous recollections of the group, producing both long-lasting and temporary errors, even when their initial memory was strong and accurate. Functional brain imaging revealed that social influence modified the neuronal representation of memory. Specifically, a particular brain signature of enhanced amygdala activity and enhanced amygdala-hippocampus connectivity predicted long-lasting but not temporary memory alterations. Our findings reveal how social manipulation can alter memory and extend the known functions of the amygdala to encompass socially mediated memory distortions.
Friday, July 15, 2011
Stress and the City
The number of the world's people living in cities has increased from 30% to 50% since 1950, and by 2050 is projected to be ~70%. Many experiments, done on insects, rodents, primates, and humans, have shown that extremes of either social isolation or crowding can have harmful effects. Lederbogen et al. have now used functional magnetic resonance imaging to examine specific human brain structures that are affected by urban living, comparing people living in rural areas, towns with more than 10,000 residents, and cities with more than 100,000 residents. They replicated their findings in several separate samples, used two different stress-inducing tasks, and demonstrated that there were no effects of urbanicity on brain activation when participants performed a non-stressful cognitive task. Stress increased participants' heart rate, blood pressure, saliva cortisol, and activity in the amygdala, with city dwellers showing the largest increases. They found that participants' age, education, income, marital and family status, as well as aspects of their health, mood, personality and the amount of social support they had did not significantly influence the effects of urbanicity. Thus they suggest that living in a city environment changes brain response during a social stressor by a distinct, but mysterious, mechanism. Here is the abstract:
http://www.nature.com/nature/journal/v474/n7352/full/474452a.html
http://www.nature.com/nature/journal/v474/n7352/full/nature10190.html
More than half of the world’s population now lives in cities, making the creation of a healthy urban environment a major policy priority. Cities have both health risks and benefits1, but mental health is negatively affected: mood and anxiety disorders are more prevalent in city dwellers and the incidence of schizophrenia is strongly increased in people born and raised in cities. Although these findings have been widely attributed to the urban social environment, the neural processes that could mediate such associations are unknown. Here we show, using functional magnetic resonance imaging in three independent experiments, that urban upbringing and city living have dissociable impacts on social evaluative stress processing in humans. Current city living was associated with increased amygdala activity, whereas urban upbringing affected the perigenual anterior cingulate cortex, a key region for regulation of amygdala activity, negative affect and stress. These findings were regionally and behaviourally specific, as no other brain structures were affected and no urbanicity effect was seen during control experiments invoking cognitive processing without stress. Our results identify distinct neural mechanisms for an established environmental risk factor, link the urban environment for the first time to social stress processing, suggest that brain regions differ in vulnerability to this risk factor across the lifespan, and indicate that experimental interrogation of epidemiological associations is a promising strategy in social neuroscience.
http://www.nature.com/nature/journal/v474/n7352/full/474452a.html
http://www.nature.com/nature/journal/v474/n7352/full/nature10190.html
Blog Categories:
culture,
fear/anxiety/stress,
social cognition
Thursday, July 14, 2011
Effects of blue light on our memory, cognition, and circadian thythm
I ran a vision research laboratory for 30 years, and in the early 1970s found that installing natural spectrum florescent lights (with more blue wavelengths) in my research laboratory enhanced my relaxation and alertness. My graduate students and post-docs reported the same effect. Following this subject I've done posts on work documenting this effect, and then subsequently finding that blue light is the best stimulus for a visual pathway that lies outside of the classical (red/green/blue) rod and cone photoreceptor cells of our retinas, driven by a the blue sensitive visual pigment melanopsin in some inner (ganglion) cells of the retina. The amygdala, at the core of our emotional brain, receives direct projections from these light sensitive retinal ganglion cells. Activation of this system also causes changes in brain areas related to working memory. An article by Beil now points to recent work noting consequences of the fact that that blue light is especially effective in suppressing the sleep promoting hormone melatonin that regulates our diurnal sleep-wake cycle. To examine the effects of energy-efficient light bulbs and electronic gadgets with LED screens that have greatly increased levels of blue light wavelengths, some researchers at the University of Basel:
...asked 13 men to sit before a computer each evening for two weeks before going to bed. During one week, for five hours every night, the volunteers sat before an old-style fluorescent monitor emitting light composed of several colors from the visible spectrum, though very little blue. Another week, the men sat at screens backlighted by light-emitting diodes, or LEDs. This screen was twice as blue...Melatonin levels in volunteers watching the LED screens took longer to rise at night, compared with when the participants were watching the fluorescent screens, and the deficit persisted throughout the evening...The subjects also scored higher on tests of memory and cognition after exposure to blue light...The finding adds to a series of others suggesting... that exposure to blue light may keep us more awake and alert, partly by suppressing production of melatonin. An LED screen bright enough and big enough could be giving an alert stimulus at a time that will frustrate the body’s ability to go to sleep later.
Wednesday, July 13, 2011
Watching contextual memories
Our memories from a particular time and place are linked together (recall Proust's Madeleine cookie) and referred to as contextual memory. Benedict Carey points to an elegant study by Manning et al. that has studied 69 neurosurgical patients who were implanted with subdural electrode arrays and depth electrodes during treatment for drug-resistant epilepsy. As electrocorticographic (ECoG) signals were recorded, the patients volunteered to participate in a free recall memory experiment, in which they studied lists of common nouns and then attempted to recall them verbally in any order following a brief delay. Their results suggest that memory is like a streaming video that is bookmarked, both consciously and subconsciously. New memories of even abstract facts are encoded in brain-cell firing sequences that also contains information about what else was happening during and just before the memory was formed. Here is their abstract, followed by a striking figure from the paper:
Psychological theories of memory posit that when people recall a past event, they not only recover the features of the event itself, but also recover information associated with other events that occurred nearby in time. The events surrounding a target event, and the thoughts they evoke, may be considered to represent a context for the target event, helping to distinguish that event from similar events experienced at different times. The ability to reinstate this contextual information during memory search has been considered a hallmark of episodic, or event-based, memory. We sought to determine whether context reinstatement may be observed in electrical signals recorded from the human brain during episodic recall. Analyzing electrocorticographic recordings taken as 69 neurosurgical patients studied and recalled lists of words, we uncovered a neural signature of context reinstatement. Upon recalling a studied item, we found that the recorded patterns of brain activity were not only similar to the patterns observed when the item was studied, but were also similar to the patterns observed during study of neighboring list items, with similarity decreasing reliably with positional distance. The degree to which individual patients displayed this neural signature of context reinstatement was correlated with their tendency to recall neighboring list items successively. These effects were particularly strong in temporal lobe recordings. Our findings show that recalling a past event evokes a neural signature of the temporal context in which the event occurred, thus pointing to a neural basis for episodic memory.
Evidence for context reinstatement in the temporal lobe. (A) Each dot marks the location of a single electrode from our dataset in Montreal Neurological Institute space. We divided our dataset into four regions of interest: temporal lobe (blue, 1,815 electrodes), frontal lobe (red, 1,737 electrodes), parietal lobe (yellow, 512 electrodes), and occipital lobe (green, 138 electrodes).
Tuesday, July 12, 2011
Dopamine, reward, and beliefs
I want to point to comments made by Charles (The Dopamine Project) on the How we form beliefs post below. The Sapolsky video is quite entertaining.
Varies of reward in the brain.
Smith et al. do some interesting tracking of the different circuits that are active in different kinds of reward in the brain. Here is their summary (which is a bit less technical than the abstract pointed to by the link):
Reward can be separated into several components, which include sensory pleasure (liking), incentive motivation triggered by related cues (wanting), and predictive associations that allow cues to raise expectations of the pleasure to come (learning). Attraction to food in the refrigerator when hungry, for example, involves learned predictions of tasty treats, motivation to eat, and finally, pleasure enjoyed on eating. In the brain, signals for each of these components are funneled together through looping pathways connecting the nucleus accumbens with the ventral pallidum (VP), which form a circuit mediating motivation, behavior, and emotions. This circuit is crucial for healthy reward processing, and its dysfunction plays a special role in pathological drug addiction, eating disorders, and emotional disorders. However, it is not known how the different reward components are kept separate within this circuit. If they are funneled together, how are they independently encoded as distinct signals? Here, we report that distinct signatures of neuronal firing in the VP track each reward component. We also report that selective enhancements of liking vs. wanting brought about by specific neurochemical activations in nucleus accumbens can be tracked independently from one another in downstream firing of VP neurons, all without distorting signals related to prediction of reward.
Monday, July 11, 2011
Our brains are hard-wired to make poor choices about harm prevention.
Daniel Gilbert, always an engaging writer, has done a nice piece in Nature "Buried by bad decisions" and I pass on a few clips here:
…should we do everything in our power to stop global warming? To make sure terrorists don't board aeroplanes? To keep Escherichia coli out of the food supply? These seem like simple questions with easy answers only because they describe what we will do without also describing what we won't. When both are made explicit — should we keep hamburgers safe or aeroplanes safe? — these simple questions become vexing. Harm prevention often seems like a moral imperative, but because every yes entails a no, it is actually a practical choice. ..research shows that when human beings make decisions, they tend to focus on what they are getting and forget about what we are forgoing. For example, people are more likely to buy an item when they are asked to choose between buying and not buying it than when they are asked to choose between buying the item and keeping their money “for other purchases”. Although “not buying” and “keeping one's money” are the same thing, the latter phrase reminds people of something they know but typically fail to consider: buying one thing means not buying another.
In the seventeenth century, Blaise Pascal and Pierre de Fermat derived the optimal strategy for betting on games of chance, and in the process demonstrated that wise choices about harm prevention are always the product of two estimates: an estimate of odds (how likely is the harmful event?) and an estimate of consequences (how much harm will it cause?). If we know which harm is most likely and which harm is most severe, then we know which harm to prevent. We should spend less to prevent a natural disaster that will probably leave 3,000 people homeless than a communicable disease that will certainly leave 3 million people dead, and this is perfectly obvious to everyone….Except when it isn't.
Our brains were optimized for finding food and mates on the African savannah and not for estimating the likelihood of a core breach or the impact of overfishing. Nature has installed in each of us a threat-detection system that is exquisitely sensitive to the kinds of threats our ancestors faced — a slithering snake, a romantic rival, a band of men waving sticks — but that is remarkably insensitive to the odds and consequences of the threats we face today…Because we specialize in understanding other minds, we are hypersensitive to the harms those minds produce..we worry more about shoe-bombers than influenza, despite the fact that one kills roughly 400,000 people per year and the other kills roughly none. We worry more about our children being kidnapped by strangers than about becoming obese, despite the fact that abduction is rare and diabetes is not.
We are especially concerned when threats human agents produce are to our dignity, values and honor…Our obsession with morality can also discourage us from embracing practical solutions to pressing problems. The taboo against selling our bodies means that people who have money and need a kidney must die so that people who need money and have a spare kidney can starve. Economic models suggest that drug abuse would decline if drugs were taxed rather than banned7, but many people have zero tolerance for policies that permit immoral behaviour even if they drastically reduce its frequency.
Our species' sociality has always been its greatest advantage, but it may also be its undoing. Because we see the world through a lens of friends and enemies, heroes and villains, alliances and betrayals, virtue and vice, credit and blame, we are riveted by the dramas that matter least and apathetic to the dangers that matter most. We will change our lives to save a child but not our light bulbs to save them all.
What are we to do about the mismatch between the way we think and the problems we should be thinking about? One solution is to frame problems in ways that appeal to our nature. For example, when threats are described as moral violations, apathy often turns to action. Texas highways were awash in litter until 1986, when the state adopted a slogan — 'Don't mess with Texas' — that made littering an insult to the honour of every proud Texan, at which point littering decreased by 72%.
The other way to deal with the mismatch between the threats we face and the way we think is to change the way we think. People are capable of thinking rationally about odds and consequences, and it isn't hard to teach them. Research shows that a simple five-minute lesson dramatically improves people's decision-making in new domains a month later10, and yet that is five minutes more than most people ever get. We teach high-school students how to read Chaucer and do trigonometry, but not how to think rationally about the problems that could extinguish their species.
Blog Categories:
acting/choosing,
emotion,
evolutionary psychology,
human evolution
Friday, July 08, 2011
How we form beliefs
A.C. Grayling offers a review of Michael Shermer's latest book "The Believing Brain: From Ghosts and Gods to Politics and Conspiracies — How We Construct Beliefs and Reinforce Them as Truths," which looks like a fascinating read. Shermer is a psychology professor, the founder of Skeptic magazine and resident sceptical columnist for Scientific American (I've done MindBlog posts on several of these columns). Grayling does such a concise job of summing up Shermer's main points that I pass on chunks of the review here (Sigh...like many of you, I suspect, I read many more reviews of books than actual books.)
Two long-standing observations about human cognitive behaviour provide Michael Shermer with the fundamentals of his account of how people form beliefs. One is the brain's readiness to perceive patterns even in random phenomena. The other is its readiness to nominate agency — intentional action — as the cause of natural events.
Both explain belief-formation in general, not just religious or supernaturalistic belief. Shermer, however, has a particular interest in the latter, and much of his absorbing and comprehensive book addresses the widespread human inclination to believe in gods, ghosts, aliens, conspiracies and the importance of coincidences.
The important point, Shermer says, is that we form our beliefs first and then look for evidence in support of them afterwards. He gives the names 'patternicity' and 'agenticity' to the brain's pattern-seeking and agency-attributing propensities, respectively. These underlie the diverse reasons why we form particular beliefs from subjective, personal and emotional promptings, in social and historical environments that influence their content.
As a 'belief engine', the brain is always seeking to find meaning in the information that pours into it. Once it has constructed a belief, it rationalizes it with explanations, almost always after the event. The brain thus becomes invested in the beliefs, and reinforces them by looking for supporting evidence while blinding itself to anything contrary. Shermer describes this process as “belief-dependent realism” — what we believe determines our reality, not the other way around.
He offers an evolution-based analysis of why people are prone to forming supernatural beliefs based on patternicity and agenticity. Our ancestors did well to wonder whether rustling in the grass indicated a predator, even if it was just the breeze. Spotting a significant pattern in the data may have meant an intentional agent was about to pounce.
Problems arise when thinking like this is unconstrained, he says. Passionate investment in beliefs can lead to intolerance and conflict, as history tragically attests. Shermer gives chilling examples of how dangerous belief can be when it is maintained against all evidence; this is especially true in pseudo-science, exemplified by the death of a ten-year-old girl who suffocated during the cruel 'attachment therapy' once briefly popular in the United States in the late 1990s.
Shermer's account implies that we are far from being rational and deliberative thinkers, as the Enlightenment painted us. Patternicity leads us to see significance in mere 'noise' as well as in meaningful data; agenticity makes us ascribe purpose to the source of those meanings. How did we ever arrive at more objective and organized knowledge of the world? How do we tell the difference between noise and data?
His answer is science. “Despite the subjectivity of our psychologies, relatively objective knowledge is available,” Shermer writes. This is right, although common sense and experience surely did much to make our ancestors conform to the objective facts long before experimental science came into being; they would not have survived otherwise.
Powerful support for Shermer's analysis emerges from accounts he gives of highly respected scientists who hold religious beliefs, such as US geneticist Francis Collins. Although religious scientists are few, they are an interesting phenomenon, exhibiting the impermeability of the internal barrier that allows simultaneous commitments to science and faith. This remark will be regarded as outrageous by believing scientists, who think that they are as rational in their temples as in their laboratories, but scarcely any of them would accept the challenge to mount a controlled experiment to test the major claims of their faith, such as asking the deity to regrow a severed limb for an accident victim.
Shermer deals with the idea that theistic belief is an evolved, hard-wired phenomenon, an idea that is fashionable at present. The existence of atheists is partial evidence against it. More so is that the god-believing religions are very young in historical terms; they seem to have developed after and perhaps because of agriculture and associated settled urban life, and are therefore less than 10,000 years old.
The animism that preceded these religions, and which survives today in some traditional societies such as those of New Guinea and the Kalahari Desert, is fully explained by Shermer's agenticity concept. It is not religion but proto-science — an attempt to explain natural phenomena by analogy with the one causative power our ancestors knew well: their own agency. Instead of developing into science, this doubtless degenerated into superstition in the hands of emerging priestly castes or for other reasons, but it does not suggest a 'god gene' of the kind supposed for history's young religions with their monarchical deities.
This stimulating book summarizes what is likely to prove the right view of how our brains secrete religious and superstitious belief. Knowledge is power: the corrective of the scientific method, one hopes, can rescue us from ourselves in this respect.
Blog Categories:
culture/politics,
evolutionary psychology,
human evolution,
religion
Married, with Infidelities
I thoroughly enjoyed reading this article by Mark Oppenheimer in the Sunday NYTimes Magazine. It focuses on the ideas of Dan Savage, who is gay,a devoted husband, proud father, and sex columnist (I am a devoted reader of his weekly column in The Onion). Savage argues that marriage should be about stability, not monogamy.
Thursday, July 07, 2011
Emotion hot spots in our brain - modern phrenology
I am guilty, as well as much of the modern press, of using the discredited shortcut of associating specific emotions with specific brain areas (amygdala = fear; insula = revulsion; anterior cingulate = subjective pain; etc.) rather than noting that none of these emotions can exist in the absence of an extensive network of interacting brain areas. This is the modern equivalent of the 19th century phrenologists who judged character traits by bumps on the skull. I want to pass on the abstract of a meta-analytic review of the brain basis of emotion by Lindquist et al. currently under review by BBS, which rather nails this point. (Email me if you are interested in a copy.) The article has some nice graphics of brain regions they associate with two major approaches: "the locationist approach (i.e., the hypothesis that discrete emotion categories consistently and specifically correspond to distinct brain regions) with the psychological constructionist approach (i.e., the hypothesis that discrete emotion categories are constructed of more general brain networks not specific to those categories). Here is their abstract:
Researchers have wondered how the brain creates emotions since the early days of psychological science. With a surge of studies in affective neuroscience in recent decades, scientists are poised to answer this question. In this paper, we present a meta-analytic summary of the human neuroimaging literature on emotion. We compare the locationist approach (i.e., the hypothesis that discrete emotion categories consistently and specifically correspond to distinct brain regions) with the psychological constructionist approach (i.e., the hypothesis that discrete emotion categories are constructed of more general brain networks not specific to those categories) to better understand the brain basis of emotion. We review both locationist and psychological constructionist hypotheses of brain-emotion correspondence and report metaanalytic findings bearing on these hypotheses. Overall, we found little evidence that discrete emotion categories can be consistently and specifically localized to distinct brain regions. Instead, we found evidence that is consistent with a psychological constructionist approach to the mind: a set of interacting brain regions commonly involved in basic psychological operations of both an emotional and non-emotional nature are active during emotion experience and perception across a range of discrete emotion categories.
Wednesday, July 06, 2011
We are lost in thought.
Some clips from Sam Harris' contribution to this year's Edge Question "What scientific concept would improve everybody's cognitive toolkit?"
While most of us go through life feeling that we are the thinker of our thoughts and the experiencer of our experience, from the perspective of science we know that this is a distorted view. There is no discrete self or ego lurking like a minotaur in the labyrinth of the brain. There is no region of cortex or pathway of neural processing that occupies a privileged position with respect to our personhood. There is no unchanging "center of narrative gravity" (to use Daniel Dennett's phrase). In subjective terms, however, there seems to be one — to most of us, most of the time.
Our contemplative traditions (Hindu, Buddhist, Christian, Muslim, Jewish, etc.) also suggest, to varying degrees and with greater or lesser precision, that we live in the grip of a cognitive illusion. But the alternative to our captivity is almost always viewed through the lens of religious dogma. A Christian will recite the Lord's Prayer continuously over a weekend, experience a profound sense of clarity and peace, and judge this mental state to be fully corroborative of the doctrine of Christianity; A Hindu will spend an evening singing devotional songs to Krishna, feel suddenly free of his conventional sense of self, and conclude that his chosen deity has showered him with grace; a Sufi will spend hours whirling in circles, pierce the veil of thought for a time, and believe that he has established a direct connection to Allah.
The universality of these phenomena refutes the sectarian claims of any one religion. And, given that contemplatives generally present their experiences of self-transcendence as inseparable from their associated theology, mythology, and metaphysics, it is no surprise that scientists and nonbelievers tend to view their reports as the product of disordered minds, or as exaggerated accounts of far more common mental states — like scientific awe, aesthetic enjoyment, artistic inspiration, etc.
Our religions are clearly false, even if certain classically religious experiences are worth having. If we want to actually understand the mind, and overcome some of the most dangerous and enduring sources of conflict in our world, we must begin thinking about the full spectrum of human experience in the context of science.
But we must first realize that we are lost in thought.
Tuesday, July 05, 2011
Introspection and shyness - evolutionary tactic?
I have previously pointed to the work of Jerome Kagan at Harvard; who, along with others, has shown that some of us are born with a predisposition to be timid and more anxious. The temperament we display in early childhood (introvesion versus extroversion, high versus low reactivity, anxiety in unfamiliar versus familiar situations, etc) is largely genetically determined and persists through life. In this vein Susan Cain has recently offered an interesting article on shyness. She first notes the re-framing of shyness into "Social Anxiety Disorder" by drug company TV adds seeking to sell serotonin reuptake inhibitors (S.S.R.I.), cited Zoloft advertisements:
...the ad’s insinuation aside, it’s also possible the young woman is “just shy,” or introverted — traits our society disfavors. One way we manifest this bias is by encouraging perfectly healthy shy people to see themselves as ill...Social anxiety disorder did not officially exist until it appeared the 1980 Diagnostic and Statistical Manual, the DSM-III, the psychiatrist’s bible of mental disorders, under the name “social phobia.” It was not widely known until the 1990s, when pharmaceutical companies received F.D.A. approval to treat social anxiety with S.S.R.I.’s and poured tens of millions of dollars into advertising its existence...Though the DSM did not set out to pathologize shyness, it risks doing so, and has twice come close to identifying introversion as a disorder, too. (Shyness and introversion are not the same thing. Shy people fear negative judgment; introverts simply prefer quiet, minimally stimulating environments.)Cain's article continues with an interesting discussion of the respective advantages and disadvantages of being a sitter or a rover.
...shy and introverted people have been part of our species for a very long time, often in leadership positions...We find them in recent history, in figures like Charles Darwin, Marcel Proust and Albert Einstein, and, in contemporary times: think of Google’s Larry Page, or Harry Potter’s creator, J. K. Rowling.
...We even find “introverts” in the animal kingdom, where 15 percent to 20 percent of many species are watchful, slow-to-warm-up types who stick to the sidelines (sometimes called “sitters”) while the other 80 percent are “rovers” who sally forth without paying much attention to their surroundings. Sitters and rovers favor different survival strategies, which could be summed up as the sitter’s “Look before you leap” versus the rover’s inclination to “Just do it!” Each strategy reaps different rewards.
IN an illustrative experiment, David Sloan Wilson, a Binghamton evolutionary biologist, dropped metal traps into a pond of pumpkinseed sunfish. The “rover” fish couldn’t help but investigate — and were immediately caught. But the “sitter” fish stayed back, making it impossible for Professor Wilson to capture them. Had Professor Wilson’s traps posed a real threat, only the sitters would have survived. But had the sitters taken Zoloft and become more like bold rovers, the entire family of pumpkinseed sunfish would have been wiped out. “Anxiety” about the trap saved the fishes’ lives.
Next, Professor Wilson used fishing nets to catch both types of fish; when he carried them back to his lab, he noted that the rovers quickly acclimated to their new environment and started eating a full five days earlier than their sitter brethren. In this situation, the rovers were the likely survivors. “There is no single best ... [animal] personality,” Professor Wilson concludes in his book, “Evolution for Everyone,” “but rather a diversity of personalities maintained by natural selection.”
The same might be said of humans, 15 percent to 20 percent of whom are also born with sitter-like temperaments that predispose them to shyness and introversion. (The overall incidence of shyness and introversion is higher — 40 percent of the population for shyness, according to the psychology professor Jonathan Cheek, and 50 percent for introversion. Conversely, some born sitters never become shy or introverted at all.)
Monday, July 04, 2011
MindBlog retrospective - 3rd and 1st person narrative in personality change
Over the past few weeks, I've been scanning the titles of old MindBlog posts (all 2,588 of them, taken 300 at a time because fatigue sets in very quickly in such an activity), glancing through the contents of the ones I recall as being most interesting to me, and assembling a list of ~80 reflecting some major themes. I am struck by the number of REALLY INTERESTING items that I had COMPLETELY forgotten about. (An illustration is the paragraph starting below with the graphic which is a repeat of a post from May 30, 2007.) It frustrates me that I have lost from recall so much good material. And, of course, it is also frustrating that the insight we do mange to retain will not necessarily change us (the subject of this March 23, 2006 post.)
Benedict Carey writes a piece in the Tuesday NY Times science section (PDF here) reviewing work done by a number of researchers on on how the stories people tell themselves (and others) about themselves do or don't help with making adaptive behavior changes. Third person narratives, in which subjects view themselves from a distance - as actors in their own narrative play - correlate with a higher sense of personal power and ability to make personality changes. First person narratives - in which the subject describes the experience of being immersed in their personal plays - are more likely than third person narratives to correlate with passivity and feeling powerless to effect change. This reminds me of Marc Hauser's distinction of being a moral agent or a moral patient. The third person can be a more metacognitive stance, thinking about oneself in a narrative script while the first person can be a less reflective acting out of the script.
Blog Categories:
deric,
morality,
psychology,
self,
self help
In the light of evolution - Cooperation and conflict
The Proceeding of the National Academy has just published the fifth in a series of Colloquia under the general title “In the Light of Evolution.” The contents of the 17 papers presented are free online, and I thought I would pass on the abstracts of two broad review articles on human evolution:
From Silk and House, "Evolutionary foundations of human prosocial sentiments":
From Silk and House, "Evolutionary foundations of human prosocial sentiments":
A growing body of evidence shows that humans are remarkably altruistic primates. Food sharing and division of labor play an important role in all human societies, and cooperation extends beyond the bounds of close kinship and networks of reciprocating partners. In humans, altruism is motivated at least in part by empathy and concern for the welfare of others. Although altruistic behavior is well-documented in other primates, the range of altruistic behaviors in other primate species, including the great apes, is much more limited than it is in humans. Moreover, when altruism does occur among other primates, it is typically limited to familiar group members—close kin, mates, and reciprocating partners. This suggests that there may be fundamental differences in the social preferences that motivate altruism across the primate order, and there is currently considerable interest in how we came to be such unusual apes. A body of experimental studies designed to examine the phylogenetic range of prosocial sentiments and behavior is beginning to shed some light on this issue. In experimental settings, chimpanzees and tamarins do not consistently take advantage of opportunities to deliver food rewards to others, although capuchins and marmosets do deliver food rewards to others in similar kinds of tasks. Although chimpanzees do not satisfy experimental criteria for prosociality in food delivery tasks, they help others complete tasks to obtain a goal. Differences in performance across species and differences in performance across tasks are not yet fully understood and raise new questions for further study.And, from Boyd et al., "The cultural niche: Why social learning is essential for human adaptation."
In the last 60,000 y humans have expanded across the globe and now occupy a wider range than any other terrestrial species. Our ability to successfully adapt to such a diverse range of habitats is often explained in terms of our cognitive ability. Humans have relatively bigger brains and more computing power than other animals, and this allows us to figure out how to live in a wide range of environments. Here we argue that humans may be smarter than other creatures, but none of us is nearly smart enough to acquire all of the information necessary to survive in any single habitat. In even the simplest foraging societies, people depend on a vast array of tools, detailed bodies of local knowledge, and complex social arrangements and often do not understand why these tools, beliefs, and behaviors are adaptive. We owe our success to our uniquely developed ability to learn from others. This capacity enables humans to gradually accumulate information across generations and develop well-adapted tools, beliefs, and practices that are too complex for any single individual to invent during their lifetime.
Friday, July 01, 2011
MindBlog's most popular posts
I've been cruising my blog posting since MindBlog's beginning in Feb. of 2006, cherry picking the posts I think most interesting, to see if any integrative themes or bottom lines magically rise from plethora of topics that have been covered. It is slow going, I'm only up to Dec. of 2007 so far. But, I noted back then that I was occasionally posting Google Feedburner's data on "aggregate item use," i.e., the most read items. So, I just looked that up again, and here it is:
On the art of puttering...
Here is an engaging editorial from the NYTimes I've been meaning to pass on. It's sentiments strike very close to my own experience.
We are a driven people, New Yorkers. Too much to do, not enough time. We keep lists; we crowd our schedules; we look for more efficient ways to organize ourselves — we get things done when we’re not too busy planning to get things done. Even our leisure time is focused, and there is something proactive about our procrastination. We don’t merely put things off. We put things off by piling other things on top of them. As Robert Benchley once noted, “anyone can do any amount of work, provided it isn’t the work he is supposed to be doing at that moment.”
But every now and then there comes a day for puttering. You can’t put it in your book ahead of time because who knows when it will come? No one intends to putter. You simply discover, in a brief moment of self-awareness, that you have been puttering, or, as the English would say, pottering. It often begins with a lost object. Not the infuriating kind that causes you to turn the house upside down while looking at your watch, but the speculative kind. “I wonder where that is,” you think.
You begin to look. Your attention is diverted almost immediately and then diverted again. You move through the morning with a calm, oblivious focus, taking on tasks — incidental ones — in the order they present themselves, which is to say no order at all. Puttering is small-scale, stream-of-consciousness problem-solving. It is setting sail on a sea of random course changes. The day passes, and you have long since forgotten what you were looking for — or that you were looking for anything at all. You feel as though you’ve accomplished a lot, though you have no idea what. It has been a holiday from purpose.
Thursday, June 30, 2011
Consciousness - correlation is not a cause
Here are excerpts from Susan Blackmore's contribution to the Edge.org question "What scientific concept would improve everybody's cognitive toolkit?"
The phrase "correlation is not a cause" (CINAC) may be familiar to every scientist but has not found its way into everyday language, even though critical thinking and scientific understanding would improve if more people had this simple reminder in their mental toolkit.
One reason for this lack is that CINAC can be surprisingly difficult to grasp. I learned just how difficult when teaching experimental design to nurses, physiotherapists and other assorted groups. They usually understood my favourite example: imagine you are watching at a railway station. More and more people arrive until the platform is crowded, and then — hey presto — along comes a train. Did the people cause the train to arrive (A causes B)? Did the train cause the people to arrive (B causes A)? No, they both depended on a railway timetable (C caused both A and B).
Stories of health scares and psychic claims may get people's attention but understanding that a correlation is not a cause could raise levels of debate over some of today's most pressing scientific issues. For example, we know that global temperature rise correlates with increasing levels of atmospheric carbon dioxide but why? Thinking Cinacally means asking which variable causes which or whether something else causes both, with important consequences for social action and the future of life on earth.
Some say that the greatest mystery facing science is the nature of consciousness. We seem to be independent selves having consciousness and free will, and yet the more we understand how the brain works, the less room there seems to be for consciousness to do anything. A popular way of trying to solve the mystery is the hunt for the "neural correlates of consciousness". For example, we know that brain activity in parts of the motor cortex and frontal lobes correlates with conscious decisions to act. But do our conscious decisions cause the brain activity, does the brain activity cause our decisions, or are both caused by something else?
The fourth possibility is that brain activity and conscious experiences are really the same thing, just as light turned out not to be caused by electromagnetic radiation but to be electromagnetic radiation, or heat turned out to be the movement of molecules in a fluid. At the moment we have no inkling of how consciousness could be brain activity but my guess is that it will turn out that way. Once we clear away some of our delusions about the nature of our own minds, we may finally see why there is no deep mystery and our conscious experiences simply are what is going on inside our brains. If this is right then there are no neural correlates of consciousness. But whether it is or not, remembering CINAC and working slowly from correlations to causes is likely to be how this mystery is finally solved.
Wednesday, June 29, 2011
Internet use restructures the brain
An interesting study out of China by Yuan et al. does fMRI studies of the brains of Chinese college-age students self-diagnosed with "internet addiction disorder" (i.e. obsessive online game players) and finds decreased gray matter volume in the bilateral dorsolateral prefrontal cortex (DLPFC), the supplementary motor area (SMA), the orbitofrontal cortex (OFC), the cerebellum and the left rostral ACC (rACC), along with changes in deeper brain structures. It doesn't seem all that surprising that playing online games 10-12 hours a day might cause brain changes. Intensive sports or musical instrument practice also cause changes in the relevant brain areas.
Note, from Mosher's summary in the Scientific American:
Note, from Mosher's summary in the Scientific American:
...the self-assessment test, created in 1998 by psychiatrist Kimberly Young of Saint Bonaventure University in New York State, is an unofficial standard among Internet addiction researchers, and it consists of eight yes-or-no questions designed to separate online addicts from those who can manage their Internet use. (Questions range from, "Do you use the Internet as a way of escaping from problems or of relieving an anxious mood?" to "Have you taken the risk of losing a significant relationship, job, educational or career opportunity because of the Internet?".Some further clips from that summary:
...another part of the new study on Internet addiction...zeroed in on white matter tissue deep in the brain which links together various regions. The scans showed increased white matter density in the right parahippocampal gyrus, a spot also tied to memory formation and retrieval. In the left posterior limb of the internal capsule, which is linked to cognitive and executive functions, white matter density dropped relative to the rest of the brain...The abnormality in white matter in the right parahippocampal gyrus may make it harder for Internet addicts to temporarily store and retrieve information, if a recent study is correct. Meanwhile, the white matter reduction in the left posterior limb could impair decision-making abilities—including those to trump the desire to stay online and return to the real world.
Blog Categories:
brain plasticity,
human development,
technology
Tuesday, June 28, 2011
Ventromedial prefrontal cortex and judgement bias.
More from Reed Montague and colleagues in an open access article that further probes the role of the ventromedial prefrontal cortex in judgement bias:
Recent work using an art-viewing paradigm shows that monetary sponsorship of the experiment by a company (a favor) increases the valuation of paintings placed next to the sponsoring corporate logo, an effect that correlates with modulation of the ventromedial prefrontal cortex (VMPFC). We used the same art-viewing paradigm to test a prevailing idea in the domain of conflict-of-interest: that expertise in a domain insulates against judgment bias even in the presence of a monetary favor. Using a cohort of art experts, we show that monetary favors do not bias the experts’ valuation of art, an effect that correlates with a lack of modulation of the VMPFC across sponsorship conditions. The lack of sponsorship effect in the VMPFC suggests the hypothesis that their brains remove the behavioral sponsorship effect by censoring sponsorship-dependent modulation of VMPFC activity. We tested the hypothesis that prefrontal regions play a regulatory role in mediating the sponsorship effect. We show that the dorsolateral prefrontal cortex (DLPFC) is recruited in the expert group. Furthermore, we tested the hypothesis in nonexpert controls by contrasting brain responses in controls who did not show a sponsorship effect to controls who did. Changes in effective connectivity between the DLPFC and VMPFC were greater in nonexpert controls, with an absence of the sponsorship effect relative to those with a presence of the sponsorship effect. The role of the DLPFC in cognitive control and emotion regulation suggests that it removes the influence of a monetary favor by controlling responses in known valuation regions of the brain including the the VMPFC.
Monday, June 27, 2011
How our attention can be highjacked.
Here are some interesting observations by Anderson et al. on how our attention can be highjacked by stimuli irrelevant to the task at hand, causing failures of cognitive control.:
Attention selects which aspects of sensory input are brought to awareness. To promote survival and well-being, attention prioritizes stimuli both voluntarily, according to context-specific goals (e.g., searching for car keys), and involuntarily, through attentional capture driven by physical salience (e.g., looking toward a sudden noise). Valuable stimuli strongly modulate voluntary attention allocation, but there is little evidence that high-value but contextually irrelevant stimuli capture attention as a consequence of reward learning. Here we show that visual search for a salient target is slowed by the presence of an inconspicuous, task-irrelevant item that was previously associated with monetary reward during a brief training session. Thus, arbitrary and otherwise neutral stimuli imbued with value via associative learning capture attention powerfully and persistently during extinction, independently of goals and salience. Vulnerability to such value-driven attentional capture covaries across individuals with working memory capacity and trait impulsivity. This unique form of attentional capture may provide a useful model for investigating failures of cognitive control in clinical syndromes in which value assigned to stimuli conflicts with behavioral goals (e.g., addiction, obesity).
Blog Categories:
attention/perception,
memory/learning
Friday, June 24, 2011
Debate on mechanisms for change..continued
My recent post pointing to David Brooks comments on the health care debate drew a number of spirited responses, and I though I would continue this thread by passing on this link to comments by Gary Gutting on clearly distinguishing facts versus convictions.
Does cognitive training work?
From Jaeggi et al., this open access article on their most recent cognitive training studies:
Does cognitive training work? There are numerous commercial training interventions claiming to improve general mental capacity; however, the scientific evidence for such claims is sparse. Nevertheless, there is accumulating evidence that certain cognitive interventions are effective. Here we provide evidence for the effectiveness of cognitive (often called “brain”) training. However, we demonstrate that there are important individual differences that determine training and transfer. We trained elementary and middle school children by means of a videogame-like working memory task. We found that only children who considerably improved on the training task showed a performance increase on untrained fluid intelligence tasks. This improvement was larger than the improvement of a control group who trained on a knowledge-based task that did not engage working memory; further, this differential pattern remained intact even after a 3-mo hiatus from training. We conclude that cognitive training can be effective and long-lasting, but that there are limiting factors that must be considered to evaluate the effects of this training, one of which is individual differences in training performance. We propose that future research should not investigate whether cognitive training works, but rather should determine what training regimens and what training conditions result in the best transfer effects, investigate the underlying neural and cognitive mechanisms, and finally, investigate for whom cognitive training is most useful.
Thursday, June 23, 2011
Why ketamine ( 'special K') makes you happy
I've mentioned in a previous post that the club drug K may be useful for something besides the psychedelic high of going "down the K-hole." Now
Science NOW points to an article from Monteggia and colleagues who find a new pathway that partially explains why the anti-depressant effects of low doses of ketamine (used at higher levels as an anesthetic and taken recreationally as a hallucinogen) start soon after it is taken, rather than requiring weeks, as with Zoloft or Paxil. Here is a clip from the Science summary:
Science NOW points to an article from Monteggia and colleagues who find a new pathway that partially explains why the anti-depressant effects of low doses of ketamine (used at higher levels as an anesthetic and taken recreationally as a hallucinogen) start soon after it is taken, rather than requiring weeks, as with Zoloft or Paxil. Here is a clip from the Science summary:
...ketamine binds to, and blocks, a receptor in the brain called NMDAR, which triggers its anesthetic effects, so Monteggia's group used other compounds to block NMDARs in mice...the animals depression once again lessened, so the researchers knew that ketamine's antidepressant effects also depended on NMDAR. Next, the team studied how levels of certain proteins in the brain changed when mice were given ketamine. Blocking NMDARs with other compounds turns off production of some proteins, but ketamine causes the neurons to make more of a protein called BDNF (brain-derived neurotrophic factor)...The findings suggest a new set of molecules that ketamine and NMDAR affects, and that means a new set of molecules involved in depression.
...
There are two ways of activating NMDARs. Some turn on when the specific neurons fire to accomplish a task—be it learning, memorizing, or thinking. But other NMDARs are activated simply as background noise in the brain. Ketamine, the researchers showed, doesn't block the brain from activating NMDARs when it's using them to send a specific message. But it does block them from creating that background noise. Although scientists have long known about the brain's spontaneous level of background nerve firing, Monteggia's study is the first to suggest a link between such background noise and depression.
Wednesday, June 22, 2011
The visual impact of gossip
Here is an interesting bit from Anderson et al. Apparently hearing negative gossip about someone apparently activates top down brain filtering mechanisms that make it more likely that we will notice their face among conflicting stimuli:
Gossip is a form of affective information about who is friend and who is foe. We show that gossip does not influence only how a face is evaluated—it affects whether a face is seen in the first place. In two experiments, neutral faces were paired with negative, positive, or neutral gossip and were then presented alone in a binocular rivalry paradigm (faces were presented to one eye, houses to the other). In both studies, faces previously paired with negative (but not positive or neutral) gossip dominated longer in visual consciousness. These findings demonstrate that gossip, as a potent form of social affective learning, can influence vision in a completely top-down manner, independent of the basic structural features of a face.
Tuesday, June 21, 2011
Innate Euclidean geometry.
This report from Izard et al. is kind of neat:
Kant argued that Euclidean geometry is synthesized on the basis of an a priori intuition of space. This proposal inspired much behavioral research probing whether spatial navigation in humans and animals conforms to the predictions of Euclidean geometry. However, Euclidean geometry also includes concepts that transcend the perceptible, such as objects that are infinitely small or infinitely large, or statements of necessity and impossibility. We tested the hypothesis that certain aspects of nonperceptible Euclidian geometry map onto intuitions of space that are present in all humans, even in the absence of formal mathematical education. Our tests probed intuitions of points, lines, and surfaces in participants from an indigene group in the Amazon, the Mundurucu, as well as adults and age-matched children controls from the United States and France and younger US children without education in geometry. The responses of Mundurucu adults and children converged with that of mathematically educated adults and children and revealed an intuitive understanding of essential properties of Euclidean geometry. For instance, on a surface described to them as perfectly planar, the Mundurucu's estimations of the internal angles of triangles added up to ∼180 degrees, and when asked explicitly, they stated that there exists one single parallel line to any given line through a given point. These intuitions were also partially in place in the group of younger US participants. We conclude that, during childhood, humans develop geometrical intuitions that spontaneously accord with the principles of Euclidean geometry, even in the absence of training in mathematics.Added note: Galina Miklosic has done a translation of this post into Ukrainian.
Monday, June 20, 2011
The amygdala - not command central for our fear reactions?
Most of us have accepted for years, starting from LeDoux's early work, that there is an automatic unconscious 'downstairs' rapid pathway in our brain that does our most important affective processing, before other more 'upstairs' cortical networks fill in the consciousness perceptual details. A recent review by Pessoa and Adolphs (PDF here) has offered a more nuanced view, from a 'low road' to 'many roads' model for our processing the significance of affective stimuli, in which the cortex plays a much larger role in processing affective visual information than is typically acknowledged. Part of their argument is based on recent studies showing that reaction times for detecting fearful faces in a patient with complete bilateral amygdala lesions were normal, a finding now extended to several further patients.
Here is the abstract of that review:
Here is the abstract of that review:
A subcortical pathway through the superior colliculus and pulvinar to the amygdala is commonly assumed to mediate the non-conscious processing of affective visual stimuli. We review anatomical and physiological data that argue against the notion that such a pathway plays a prominent part in processing affective visual stimuli in humans. Instead, we propose that the primary role of the amygdala in visual processing, like that of the pulvinar, is to coordinate the function of cortical networks during evaluation of the biological significance of affective visual stimuli. Under this revised framework, the cortex has a more important role in emotion processing than is traditionally assumed.This review has triggered extensive commentary, and I wanted to pass on to those MindBlog readers who are into brain and emotion details PDFs of two letters outlining the issues, the critique from de Gelder et al., and the convincing and balanced (to me) response from Pessoa and Adolphs.
Article of the future...
I'm on the editorial board of one of the Elsevier journals, and so get occasional emails on things they are cooking up. Towards the end of 2011 they proclaim they will be changing what has been for 350 years the standard format of scientific articles. They offer online prototypes of their "Article of the Future," and here is their prototype for Psychology and Cognitive Science.
Looks to me like they are playing catchup with Cell Press and its associated Journals, such as Neuron, which has an interesting recent special issue on social neuroscience.
Looks to me like they are playing catchup with Cell Press and its associated Journals, such as Neuron, which has an interesting recent special issue on social neuroscience.
Friday, June 17, 2011
Why we laugh
In the June 10 issue of Science Walter Sinnott-Armstrong reviews what looks like a fascinating and fun book: "Inside Jokes Using Humor to Reverse-Engineer the Mind," by Matthew M. Hurley, Daniel C. Dennett, and Reginald B. Adams Jr. MIT Press, Cambridge, MA. (I just downloaded it to my Kindle.) The reviewer lays out their core theory:
The key to the authors' success is that they locate humor within recent cognitive science and evolutionary theory. To aid survival, our brains constantly and covertly use heuristics to generate expectations about what we will experience next, but we would be too inventive for our own good if we did not regularly search for and remove discrepancies between our expectations and our experiences. The immediate incentive to look for such discrepancies and thereby to reduce error comes from the pleasure of discovering a mistake in a currently harmless active belief that was introduced covertly. That pleasure is mirth, and humor is what produces it. Thus, humor is “a cognitive cleanup mechanism” that stains with mistaken belief before washing out the error (as in “I wondered why the Frisbee was getting bigger, and then it hit me.”). Laughter is then a public signal of our ability to clean up our minds. Because such cognitive prowess is useful, it attracts mates—both friends and sexual partners—and spreads throughout the world.
Hurley, Dennett, and Adams apply their theory to well over a hundred examples (including stupid jokes, dark humor, musical jokes, and witty remarks that are not humorous), to many apparent counterexamples (such as surprises, forgetting, riddles, and lies), and to related phenomena (such as magicians and garden-path sentences).
Thursday, June 16, 2011
Techie nirvana - Google's human android
I've gone for the cloud. On receiving an invitation (which I requested) from Google to try their beta version of Google Music (music.google.com) I've installed their music manager app which appears to be uploading my entire 23 GB iTunes library to their servers (from my university office with very high speed upload rate - much faster than would happen at home), playable from any web browser or android phone or tablet. Given how completely dependent I have become on Google's Calendar, Contact list, Mail, Phone, and Blogger applications that synch across my computers at three different locations, I have become a Google Humanoid Android (definition: Possessing human features. n. An automaton that is created from biological materials and resembles a human. Also called humanoid.) When the first really major terrorist cyber attack takes out the cloud, I will loose ego projections that have assumed almost as much importance in constituting my human self as my actual arms and legs. (Probably not, actually, since I'm writing this.)
Liszt - Années de pèlerinage - Vallee d'Obermann
This is the fourth piece played in a house concert for friends at my home on Twin Valley Road in Middleton WI, on May 22, 2011. This recording was made on June 13. The piece is from one of Liszt's three suites titled 'Years of Pilgrimage.' Obermann's Valley is from the Swiss suite which contains nine pieces written in 1848-1854. It has several romantic captions, one from Byron's Childe Harold's Pilgrimage ("Could I embody and unbosom now / That which is most within me,--could I wreak / My thoughts upon expression, and thus throw / Soul--heart--mind--passions--feelings--strong or weak-- …etc., ) and two captions from the French romantic writer Senancour's book Obermann, which includes questions like , “What do I want? Who am I? What do I ask of nature?" … This is a very histrionic and emotional piece.
The Empathetic Brain
Christian Keyser, who does research on mirror neurons at The Netherlands Institute for Neuroscience, sent me an email yesterday pointing out his new book on human empathy. My scan of the copy he sent to me finds the book to written in a friendly, engaging, and accessible style for a non-technical audience. I point it out here because it is available as a Kindle Book at Amazon, and the price is right ($3.00).
Wednesday, June 15, 2011
The quest for validation.
Out of the virtual diarrhea of commentary on Anthony Weiner's weiner, the commentary by Ross Douthat struck a chord with me, and so I muse a bit following these clips from his piece:
In the sad case of Representative Anthony Weiner’s virtual adultery, the Internet era’s defining vice has been thrown into sharp relief. It isn’t lust or smut or infidelity, though online life encourages all three. It’s a desperate, adolescent narcissism...his “partners” existed less to titillate him than to hold up mirrors to his own vanity...a growing body of research suggests that American self-involvement is actually reaching an apogee in the age of Facebook and Twitter.. In a culture increasingly defined by what Christine Rosen describes as the “constant demands to collect (friends and status), and perform (by marketing ourselves),” just being a United States congressman isn’t enough. You have to hit the House gym and look good coming out of the shower, and then find a Twitter follower who’s willing to tell you just “how big” you really are...Facebook and Twitter did not forge the culture of narcissism. But they serve as a hall of mirrors in which it flourishes as never before — a “vast virtual gallery,” as Rosen has written, whose self-portraits mainly testify to “the timeless human desire for attention.”After feeling a bit superior reading this article about 'poor Anthony Weiner' I turn it around to try this as a description of myself. Why do I write this blog, why do I put effort into piano performance and posting the videos of recent playing? In my most lucid moments I genuinely feel that the "I-it" relationship is primary, my own personal experience of immersing myself in great ideas or great music, and then secondarily sharing this experience with others. But it is also the case that another Deric, the kid who showed up at 4th grade show-and-tell with his grandfather's dress U.S. Calvary sword to impress everyone, is a motive engine. So I also stand guilty as charged above. Still, "the timeless human desire for attention" is the inborn mechanism by which our brains grow and we become selves by mirroring and then internalizing the selves of others. To do this we must grab the attention of others, and thus have a desire to perform so that they will be impressed. At some point, however, we hope to have ourselves more or less together as adults, and let go off our earlier insatiable longing for validation. (It is not surprising that the most common outlets for remnants of this longing are real or imagined fantasies of sexual attractiveness.)
Tuesday, June 14, 2011
Shame and honor drive cooperation
In Biological Letters, an interesting and simple result from Jacquet et. al.:
Can the threat of being shamed or the prospect of being honoured lead to greater cooperation? We test this hypothesis with anonymous six-player public goods experiments, an experimental paradigm used to investigate problems related to overusing common resources. We instructed the players that the two individuals who were least generous after 10 rounds would be exposed to the group. As the natural antithesis, we also test the effects of honour by revealing the identities of the two players who were most generous. The non-monetary, reputational effects induced by shame and honour each led to approximately 50 per cent higher donations to the public good when compared with the control, demonstrating that both shame and honour can drive cooperation and can help alleviate the tragedy of the commons.
Monday, June 13, 2011
Debate on optimal mechanisms for political and social change
David Brooks has done what seems to me a balanced piece on the fundamental philosophical issues underlying the current debate on reform of entitlements, role of government,etc. I find myself less reflexively opposed to his conservative sympathies after reading his description of different strategies for effecting change. The basic issue boils down to "What is the best mechanism for effecting change in enormously complex social systems." Brooks, in the tradition of the British philosopher Oakeshott (seems to me he should have referenced his own essay on Oakeshott), thinks that decentralized bottom-up market based solutions are the best way to reform medical care, noting that
...competition-based plans (favored by Republicans) have improved outcomes in many places. Such plans cover employees of the University of California and state employees in California, Wisconsin and Minnesota. They also note that the Medicare prescription drug benefit also uses a competition model. Consumers have been adept at negotiating a complex marketplace, and costs are 41 percent below expectations.The alternative (liberal, Democratic) view is that the best mechanism of change is top-down control that
...seeks to concentrate decision-making and cost-control power in the hands of centralized experts. Under the Obama health care law, a team of 15 officials will be created to discover best practices and come up with cost-cutting measures. There will also be a Center for Medicare and Medicaid Innovation in Washington to organize medical innovation. Centralized officials will decide how to set national reimbursement rates.They argue that
Health care is phenomenally complicated. Providers have much more information than consumers. Insurance companies are rapacious and are not in the business of optimizing care.Brooks:
...there is no dispositive empirical proof about which method is best — the centralized technocratic one or the decentralized market-based one. Politicians wave studies, but they’re really just reflecting their overall worldviews. Democrats have much greater faith in centralized expertise. Republicans (at least the most honest among them) believe that the world is too complicated, knowledge is too imperfect. They have much greater faith in the decentralized discovery process of the market.So here we go, another either/or Manichean kind of presentation... maybe we should reference a biological model, take a lesson from how our brains organize our behavior, both from the bottom up AND from the top down, with feedback loops continually connecting the two.
Friday, June 10, 2011
Searching for the True Self
Joshua Knobe writes a piece for The Stone, a forum for contemporary philosopers in The New York Times Opinionator. The issue posed is:
Knobe has an appointment at Yale in both Cognitive Science and in Philosophy. He is a co-editor, with Shaun Nichols, of the volume “Experimental Philosophy.” Given his cognitive science appointment, I am struck that he doesn't bring up the question of whether "The True Self" is a viable concept at all, given what we now know about how our brains clearly construct not one, but a multitude of selves, all of which are essentially confabulations tested by their utility (see the sundry web lectures I list in the left column of this blog).
...which aspect of a person counts as that person’s true self?Knobe describes an 'experimental philosophy' experiment done with another colleague that presented a series of question to liberals and conservatives and found a systematic connection between people’s own values and their judgments about the true self. Conservative participants were more inclined to say that a person’s true self had emerged on conservative items, while liberals were more inclined to say that the person’s true self had emerged on liberal items.
Many believe that the true self lies precisely in our suppressed urges and unacknowledged emotions...If we look to the philosophical tradition, we find a relatively straightforward answer to this question. This answer, endorsed by numerous different philosophers in different ways, says that what is most distinctive and essential to a human being is the capacity for rational reflection. A person might find herself having various urges, whims or fleeting emotions, but these are not who she most fundamentally is. If you want to know who she truly is, you would have to look to the moments when she stops to reflect and think about her deepest values.
...people outside the world of philosophy...are immediately drawn to the very opposite view. The true self, they suggest, lies precisely in our suppressed urges and unacknowledged emotions, while our ability to reflect is just a hindrance that gets in the way of this true self’s expression.
Knobe has an appointment at Yale in both Cognitive Science and in Philosophy. He is a co-editor, with Shaun Nichols, of the volume “Experimental Philosophy.” Given his cognitive science appointment, I am struck that he doesn't bring up the question of whether "The True Self" is a viable concept at all, given what we now know about how our brains clearly construct not one, but a multitude of selves, all of which are essentially confabulations tested by their utility (see the sundry web lectures I list in the left column of this blog).
Thursday, June 09, 2011
A devolution of modern nation states?
I've been reading Fukayama's new book on the origins of political order and the evolution, first in England, of government with the three pillars of (1) The rule of law, (2) Strong central authority, and (3) Accountability of the leader. This is the form to which advanced modern nation states nominally adhere (even if they hold sham elections, are kleptocracies lacking rule of law, or have no check on central authority - think of Russia, China, former Soviet republics, or many African states.)
It strikes me that an consequence of the ultra-connectivity allowed by the internet may be a devolution of this nation state model, as an echo chamber mechanism allows people with different political or religious philosophies - the modern equivalent of the tribes that have dominated most of human history - to sequester themselves with like minded people reinforcing and making more extreme their world view. Thus we have phenomena like our current failure of U.S. governance as conservative and liberal camps appear to care more about their tribal agendas than the viability of the larger nation state. We seem to be moving in the direction of Afganistan or Iraq, where tribal loyalties are currently preventing the formation of effective modern nation states.
(Added note on 6/10/11 - Today's NYTimes has an interesting related piece by Roger Cohenwhich is well worth reading, from which I pull this quote:
It strikes me that an consequence of the ultra-connectivity allowed by the internet may be a devolution of this nation state model, as an echo chamber mechanism allows people with different political or religious philosophies - the modern equivalent of the tribes that have dominated most of human history - to sequester themselves with like minded people reinforcing and making more extreme their world view. Thus we have phenomena like our current failure of U.S. governance as conservative and liberal camps appear to care more about their tribal agendas than the viability of the larger nation state. We seem to be moving in the direction of Afganistan or Iraq, where tribal loyalties are currently preventing the formation of effective modern nation states.
(Added note on 6/10/11 - Today's NYTimes has an interesting related piece by Roger Cohenwhich is well worth reading, from which I pull this quote:
...at a time of economic hardship, the movements in the West with momentum are nationalist — like Marine Le Pen’s National Front in France or the Tea Party movement in the United States. Tribe trumps technology’s integrative tug. But the engine of that tug is remorseless and will in time prevail.
Wednesday, June 08, 2011
Chopin Fantasy in F Minor
This is the third piece played in a house concert for friends at my home on Twin Valley Road in Middleton WI, on May 22, 2011. I'm doing just one run through of each of the pieces from that concert, this recording was made on June 3. I'm not patient enough to do the multiple takes that would be required to get a version without a section of scrambled notes happening at some unpredictable point.
Tuesday, June 07, 2011
Dopamine gene variants correlate with learning style.
In the Editor's choice section of the recent Science magazine Pamela Hines points to work by Kegel et al.:
Some children, particularly those with a more fearful temperament, are more sensitive than others to the influence of parents, teachers, and environment. Studying preschoolers, Kegel et al. attempt to link this with a particular genetic polymorphism. Children played a literacy-geared computer game that delivered instruction and assignments to all participants, but differed in whether it delivered feedback about the children's choices. A feature that distinguished the groups of children was whether they carried the long variant of the dopamine D4 receptor gene, which is associated with lower dopamine reception efficiency. Children who carried this polymorphism were more susceptible to the effects of feedback from the computer program. They outperformed the control group when feedback guided their learning, and they did worse than the control group when feedback was absent. In contrast, children with the short variant of the gene seemed to be unruffled by the presence or absence of feedback. For education, just as for shoes, a good fit to the individual produces the best result.Here is the Kegel et al. abstract:
Not every child seems equally susceptible to the same parental, educational, or environmental influences even if cognitive level is similar. This study is the first randomized controlled trial to apply the differential susceptibility paradigm to education in relation to children's genotype and early literacy skills. A randomized pretest–posttest control group design was used to examine the effects of the Intelligent Tutoring System Living Letters. Two intervention groups were created, 1 receiving feedback and 1 completing the program without feedback, and 1 control group. Carriers of the long variant of the dopamine D4 receptor gene (DRD4 7-repeat) profited most from the computer program with positive feedback, whereas they performed at the lowest level of early literacy skills in the absence of such feedback. Our findings suggest that behind modest overall educational intervention effects a strong effect on a subgroup of susceptible children may be hidden.
Blog Categories:
genes,
human development,
memory/learning
Monday, June 06, 2011
A Haydn Fantasy
This Haydn Fantasy in C Major is the second piece performed in a house concert for friends on May 22, 2011. This recording was made on June 3, 2011 on my Steinway B at Twin Valley in Middleton Wisconsin.
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