Friday, January 30, 2009

Estrogen receptors in the male medial amygdala disrupt social behavior.

A series of classic studies have shown that in Prairie Voles two neuropeptides, oxytocin and vasopressin, are primary modulators of pair-bond formation and parental behaviors. Genetic manipulations have been able to switch male behaviors between pair-bonding and promiscuous, and correlations between similar behaviors in human males and their genetic variations have been found. Recently Cushing et al. have made another observation on male voles which one expects will also be carried over to human males: Prosocial behavior correlates with a low density of estrogen receptors in the lateral amygdala, and genetic manipulations which increase the number of these receptors decrease pair-bonding and prosocial behaviors. It will be interesting to follow efforts to translate these findings to human social bonding, especially in relation to neuropsychiatric disorders characterized by an inability to form normal social bonds, such as autism. Here is their abstract:

Studies using estrogen receptor {alpha} (ER{alpha}) knock-out mice indicate that ER{alpha} masculinizes male behavior. Recent studies of ER{alpha} and male prosocial behavior have shown an inverse relationship between ER{alpha} expression in regions of the brain that regulate social behavior, including the medial amygdala (MeA), and the expression of male prosocial behavior. These studies have lead to the hypothesis that low levels of ER{alpha} are necessary to "permit" the expression of high levels of male prosocial behavior. To test this, viral vectors were used to enhance ER{alpha} in male prairie voles (Microtus ochrogaster), which display high levels of prosocial behavior and low levels of MeA ER{alpha}. Adult male prairie voles were transfected with ER{alpha} in the MeA (MeA-ER{alpha}) or the caudate–putamen (ER{alpha} control) or luciferase (MeA-site-specific control), and 3 weeks later tested for spontaneous alloparental behavior and partner preference. Enhancing ER{alpha} in the MeA altered/reduced male prosocial behavior. Only one-third of MeA-ER{alpha} males, compared with all control males, were alloparental. MeA-ER{alpha} males also displayed a significant preference for a novel female. This is a critical finding because the manipulations of neuropeptides, oxytocin and vasopressin, can inhibit the formation of a partner preference, but do not lead to the formation of a preference for a novel female. The results support the hypothesis that low levels of ER{alpha} are necessary for high levels of male prosocial behavior, and provide the first direct evidence that site-specific ER{alpha} expression plays a critical role in the expression of male prosocial behavior.

The dolphin as gourmet chef: how to prepare cuttlefish

From the abstract of Finn et al. :

...a wild female Indo-Pacific bottlenose dolphin (Tursiops aduncus) was observed and recorded repeatedly catching, killing and preparing cuttlefish for consumption using a specific and ordered sequence of behaviours. Cuttlefish were herded to a sand substrate, pinned to the seafloor, killed by downward thrust, raised mid-water and beaten by the dolphin with its snout until the ink was released and drained. The deceased cuttlefish was then returned to the seafloor, inverted and forced along the sand substrate in order to strip the thin dorsal layer of skin off the mantle, thus releasing the buoyant calcareous cuttlebone. This stepped behavioural sequence significantly improves prey quality through 1) removal of the ink (with constituent melanin and tyrosine), and 2) the calcareous cuttlebone.

Thursday, January 29, 2009

Soul-travel for selfless beings

Thomas Metzinger, one of my favorite philosophers, offers this piece on this years Edge.org question "What will change everything."

John Brockman points out that new technology leads not only to new ways of perceiving ourselves, but also to a process he calls "recreating ourselves." Could this become true in an even deeper and more radical way than through gene-technology? The answer is yes.

It is entirely plausible that we may one day directly control virtual models of our own bodies directly with our brain. In 2007, I first experienced taking control of a computer-generated whole-body model myself. It took place in a virtual reality lab where my own physical motions were filmed by 18 cameras picking up signals from sensors attached to my body. Over the past two years, different research groups in Switzerland, England, Germany and Sweden have demonstrated how, in a passive condition, subjects can consciously identify with the content of a computer-generated virtual body representation, fully re-locating the phenomenal sense of self into an artificial, visual model of their body.

In 2008, in another experiment, we saw that a monkey on a treadmill could control the real-time walking patterns a humanoid robot via a brain-machine interface directly implanted into its brain. The synchronized robot was in Japan, while the poor monkey was located thousands of miles away, in the US. Even after it stopped walking, the monkey was able to sustain locomotion of the synchronized robot for a few minutes—just by using the visual feedback transmitted from Japan plus his own "thoughts" (whatever that may turn out to be).

Now imagine two further steps.

First, we manage to selectively block the high-bandwidth "interoceptive" input into the human self-model—all the gut feelings and the incessant flow of inner body perceptions that anchor the conscious self in the physical body. After all, we already have selective motor control for an artificial body-model and robust phenomenal self-identification via touch and sight. By blocking the internal self-perception of the body, we could be able to suspend the persistent causal link to the physical body.

Second, we develop richer and more complex avatars, virtual agents emulating not only the proprioceptive feedback generated by situated movement, but also certain abstract aspects of ongoing global control itself—new tools, as Brockman would call them. Then suddenly it happens that the functional core process initiating the complex control loop connecting physical and virtual body jumps from the biological brain into the avatar.

I don't believe this will happen tomorrow. I also don't believe that it would change everything. But it would change a lot.

Neural correlates of third party punishment.

Legal decision making involves assessing the defendant's responsibility for the crime and choosing an appropriate punishment. To determine the neural correlates of these processes, Buckholtz et al. have used functional MRI to scan volunteers who made legal decisions based on written scenarios. The level of activity in the right dorsolateral prefrontal cortex correlated with the level of responsibility that the volunteers assigned to the defendant, whereas activity in the amygdala, the medial prefrontal cortex and the posterior cingulate cortex predicted punishment magnitude, indicating that distinct neural systems underlie the two processes in legal decision making. Here is their abstract:

Legal decision-making in criminal contexts includes two essential functions performed by impartial “third parties:” assessing responsibility and determining an appropriate punishment. To explore the neural underpinnings of these processes, we scanned subjects with fMRI while they determined the appropriate punishment for crimes that varied in perpetrator responsibility and crime severity. Activity within regions linked to affective processing (amygdala, medial prefrontal and posterior cingulate cortex) predicted punishment magnitude for a range of criminal scenarios. By contrast, activity in right dorsolateral prefrontal cortex distinguished between scenarios on the basis of criminal responsibility, suggesting that it plays a key role in third-party punishment. The same prefrontal region has previously been shown to be involved in punishing unfair economic behavior in two-party interactions, raising the possibility that the cognitive processes supporting third-party legal decision-making and second-party economic norm enforcement may be supported by a common neural mechanism in human prefrontal cortex.

Wednesday, January 28, 2009

MindBlog's first PodCast: "The I-Illusion"

Posting the podcast of the web radio show this past Monday motivated me to follow through on composing a few of my own podcasts for MindBlog. When I asked for opinions on this possibility last Oct. 31, most respondents indicated a preference for 5-30 min chunks of material. I decided to warm up by translating a lecture I have given, "The I-Illusion," into podcast form. (Here is the mp3 (10 Mb) download.) You can find the web version here. The podcast version is a condensed form of the web lecture (It is 45 min instead of 1 hr), but it has more recent material not included in the web lecture.

Seeing who we hear and hearing who we see

In an article with the title of this post Seyfarth and Cheney make the following comments on work by Proops et al.

Imagine that you're working in your office and you hear two voices outside in the hallway. Both are familiar. You immediately picture the individuals involved. You walk out to join them and there they are, looking exactly as you'd imagined. Effortlessly and unconsciously you have just performed two actions of great interest to cognitive scientists: cross-modal perception (in this case, by using auditory information to create a visual image) and individual recognition (the identification of a specific person according to a rich, multimodal, and individually distinct set of cues, and the placement of that individual in a society of many others). Proops, McComb, and Reby show that horses do it, too, and just as routinely, without any special training. The result, although not surprising, is nonetheless the first clear demonstration that a non-human animal recognizes members of its own species across sensory modalities. It raises intriguing questions about the origins of conceptual knowledge and the extent to which brain mechanisms in many species—birds, mammals, as well as humans—are essentially multisensory.

According to a traditional view, multisensory integration takes place only after extensive unisensory processing has occurred. Multimodal (or amodal) integration is a higher-order process that occurs in different areas from unimodal sensory processing, and different species may or may not be capable of multisensory integration...An alternative view argues that, although different sensory systems can operate on their own, sensory integration is rapid, pervasive, and widely distributed across species. The result is a distributed circuit of modality-specific subsystems, linked together to form a multimodal percept...A third view argues that many neurons are multisensory, able to respond to stimuli in either the visual or the auditory domain (for example), and capable of integrating sensory information at the level of a single neuron as long as the two sorts of information are congruent. As a result, “much, if not all, of neocortex is multisensory”. By this account, perceptual development does not occur in one sensory modality at a time but is integrated from the start.
Here is the experiment as described in the Proops et al. abstract:
...we use a cross-modal expectancy violation paradigm to provide a clear and systematic demonstration of cross-modal individual recognition in a nonhuman animal: the domestic horse. Subjects watched a herd member being led past them before the individual went of view, and a call from that or a different associate was played from a loudspeaker positioned close to the point of disappearance. When horses were shown one associate and then the call of a different associate was played, they responded more quickly and looked significantly longer in the direction of the call than when the call matched the herd member just seen, an indication that the incongruent combination violated their expectations. Thus, horses appear to possess a cross-modal representation of known individuals containing unique auditory and visual/olfactory information. Our paradigm could provide a powerful way to study individual recognition across a wide range of species.

Eating dirt is good for you.

I have always attributed my robust immune system (I don't get colds) to the fact that when I was 1-5 years old I was crawling or running around barefoot in the hot Texas summer, eating dirt, pill bugs, and dog shit. Brody does a nice summary of what is now the accepted view: that exposure while young to a diverse array of bacteria, viruses, and worms trains the immune system in what is and is not important, essentially programs it for later adult life. Children raised in super hygiene environments are more likely to develop allergies, asthma, and autoimmune disorders.

Tuesday, January 27, 2009

Seeing ourselves as eddies in the stream of entropy

Of the hundreds of essays written to commemorate the 200th anniversary of Charles Darwin's birth, I think one of the most engaging is offered by Matt Ridley in the Spectator magazine. A few clips:

Living beings are eddies in the stream of entropy. That is to say, while the universe gradually becomes more homogeneous and disordered, little parts of it can reverse the trend and become briefly more ordered and complex by capturing packets of energy. It happens each time a baby is conceived. Built by 20,000 genes that turn each other on and off in a symphony of great precision, and equipped with a brain of ten trillion synapses, each refined and remodeled by early and continuing experience, you are a thing of exquisite neatness, powered by glucose. Says Darwin, this came about by bottom-up emergence, not top-down dirigisme. Faithful reproduction, occasional random variation and selective survival can be a surprisingly progressive and cumulative force: it can gradually build things of immense complexity. Indeed, it can make something far more complex than a conscious, deliberate designer ever could: with apologies to William Paley and Richard Dawkins, it can make a watchmaker.

Malthus taught Darwin the bleak lesson that overbreeding must end in pestilence, famine or violence — and hence gave him the insight that in a struggle for existence, survival could be selective. But the notion that, with random variation, this selective survival could then generate complexity and sophistication where there had been none before, that it is a cumulative and creative force, is entirely his. It is also one that applies to more than the bodies of living beings.

Technology is a case in point. Although engineers are under the fond illusion that they design things, nearly all of what they do consists of nudging forward descent with modification. Every technology has traceable ancestry; ‘to create is to recombine’ said the geneticist François Jacob. The first motor car was once described by the historian L.T.C. Rolt as ‘sired by the bicycle out of the horse carriage’. Just like living systems, technologies experience mutation (such as the invention of the spinning jenny), reproduction (the rapid mechanisation of the cotton industry as manufacturers copied each others’ machines), sex (Samuel Crompton’s combination of water frame and jenny to make a ‘mule’), competition (different designs competing in the early cotton mills), extinction (the spinning jenny was obsolete by 1800), and increasing complexity (modern cotton mills are electrified and computerised).

Software inventors have learnt to recognise the power of trial and error rather than deliberate design. Beginning with ‘genetic algorithms’ in the 1980s, they designed programmes that would experiment with changes in their sequence till they solved the problem set for them. Then gradually the open-source software movement emerged by which users themselves altered programmes and shared their improvements with each other. Linux and Apache are operating systems designed by such democratic methods, but the practice has long spread beyond programmers. Wikipedia is a bottom-up knowledge repository and, though far from flawless, is proving easily capable, even in its first flush of youth, of matching expert-written encyclopaedias for accuracy and reach. It grows by natural selection among edits.

The internet is an increasingly Darwinian place, where decentralised, self-organising sophistication holds sway: swarm intelligence is the fashionable term. Trey Ratcliff, founder of a computer games company in Texas, tells me he feels more like a victim than a designer of technology’s evolution: ‘saying Edison invented the phonograph is like saying a spider invented silk’.

The Machine Stops

A large component of the current financial meltdown results from people trusting that they were being cared for by complex financial instruments that neither they nor the people who designed them really understood. It recently struck me that this sort of situation was described long ago by E.M Forster in his prescient 1909 science fiction short story "The Machine Stops." I found the text here and very much enjoyed re-reading the story. A synopsis is given by the wikipedia entry, and it can be downloaded in the various electronic formats.

Monday, January 26, 2009

MindBlog does a gig on a happiness webcast/podcast

With some trepidation I signed on to be a talking head neuroscience 'expert' on the "Make Me Happy!" Radio Show with Drs. Aymee Coget and Bob Nozik as hosts last Friday, 4-5 p.m. pacific time. The one hour show is podcast until this friday at www.AdviceRadio.com, or you can download the .mp3 file here. My interview starts 7 1/2 minutes into the program after a somewhat loopy new-agey california-style introduction. I just listened to the first few minutes of the interview, and I guess it is OK, although I'm pained that the number of "uh's" and "y'knows" is right up there with Caroline Kennedy's. I should mention to those of you who responded to my 'would you like some podcasts from MindBlog?' question affirmatively that my intentions are still good, but I just haven't found time to actually start doing them. Doing these postings and also keeping up piano performance and chamber music seems to take up more time than I have.

A new kind of mind.

In response to this years Edge question "What would change everything - What game-changing scientific ideas and developments do you expect to live to see?", Kevin Kelly sees a new kind of cheap, powerful, ubiquitous artificial intelligence, the kind of synthetic mind that learns and improves itself.

...the snowballing success of Google this past decade suggests the coming AI will not be bounded inside a definable device. It will be on the web, like the web. The more people that use the web, the more it learns. The more it knows, the more we use it. The smarter it gets, the more money it makes, the smarter it will get, the more we will use it. The smartness of the web is on an increasing-returns curve, self-accelerating each time someone clicks on a link or creates a link. Instead of dozens of geniuses trying to program an AI in a university lab, there are billion people training the dim glimmers of intelligence arising between the quadrillion hyperlinks on the web. Long before the computing capacity of a plug-in computer overtakes the supposed computing capacity of a human brain, the web—encompassing all its connected computing chips—will dwarf the brain. In fact it already has.

When this emerging AI, or ai, arrives it won't even be recognized as intelligence at first. Its very ubiquity will hide it. We'll use its growing smartness for all kinds of humdrum chores, including scientific measurements and modeling, but because the smartness lives on thin bits of code spread across the globe in windowless boring warehouses, and it lacks a unified body, it will be faceless. You can reach this distributed intelligence in a million ways, through any digital screen anywhere on earth, so it will be hard to say where it is. And because this synthetic intelligence is a combination of human intelligence (all past human learning, all current humans online) and the coveted zip of fast alien digital memory, it will be difficult to pinpoint what it is as well. Is it our memory, or a consensual agreement? Are we searching it, or is it searching us?

Most downloaded consciousness papers of 2008

The ASSC (Association for the Scientific Study of Consciousness) keeps an eprints archive from which you can download a large number of papers. They report the following as the most downloaded papers of 2008:

Metacognition and Consciousness, Koriat, A. (2006) In: Cambridge handbook of consciousness. Cambridge University Press, New York, USA. http://eprints.assc.caltech.edu/175/ 15281 downloads from 57 countries

Methods for studying unconscious learning, Destrebecqz, Arnaud and Peigneux, Philippe (2005) In: Progress in Brain Research. Elsevier, pp. 69-80. http://eprints.assc.caltech.edu/170/ 14015 downloads from 64 countries

Crossmodal interactions: lessons from synesthesia, Sagiv, Noam and Ward, Jamie (2006) In: Visual Perception, Part 2 - Fundamentals of Awareness: Multi-Sensory Integration and High-Order Perception. Progress in Brain Research, Volume 155. Elsevier, pp. 259-271. ISBN 0444519270 http://eprints.assc.caltech.edu/224/ 13193 downloads from 43 countries

Inverse Zombies, Anesthesia Awareness, and the Hard Problem of Unconsciousness, Mashour, George A. (2007) In: 11th Annual Meeting of the ASSC, Las Vegas. http://eprints.assc.caltech.edu/294/ 11421 downloads from 69 countries

Conscious, preconscious, and subliminal processing: a testable taxonomy, Dehaene, Stanislas and Changeux, Jean-Pierre and Naccache, Lionel and Sackur, Jérôme and Sergent, Claire (2006) Trends in Cognitive Science, 10 (5). pp. 204-211. http://eprints.assc.caltech.edu/20/ 10094 downloads from 51 countries

Friday, January 23, 2009

Getting the dead to talk back.

In his January Scientific American column, "Skeptic", Michael Shermer writes about his experience as the token scientist invited to Univ-Con, a paranormal conference organized by Ryan Buell, the telegenic host of A&E’s television unreality series Paranormal State.

“Is Matthew there?” asked Cheyenne, directing her voice toward the box on the table in hopes that her brother would come through from the other side. “Yes,” the reply came. With the connection “validated,” Cheyenne shakily continued: “Was the suicide a mistake?” The speaker crackled, “My death was a mistake.”... Cheyenne’s life-affirming messages were coming out of Thomas Edison’s “Telephone to the Dead”—or at least a facsimile of a rumored machine that the great inventor never built. It was just one of many readings that day (at $90 a pop) conducted by Christopher Moon, senior editor and president of Haunted Times magazine.

I couldn’t hear Cheyenne’s brother, mother or any other incorporeal spirits, until Moon interpreted the random noises emanating from the machine that, he explained to me, was created by a Colorado man named Frank Sumption. “Frank’s Box,” according to its inventor, “consists of a random voltage generator, which is used to tune an AM receiver module rapidly. The audio from the tuner (“raw audio”) is amplified and fed to an echo chamber, where the spirits manipulate it to form their voices.” Apparently doing so is difficult for the spirits, so Moon employs the help of “Tyler,” a spirit “technician,” whom he calls on to corral wayward spirits to within earshot of the receiver. What it sounded like was the rapid twirling of a radio dial so that only noises and word fragments were audible.

“Well, since we know how easy it is for our brains to find meaningful patterns in meaningless noise,” I continued, “how can you tell the difference between a dead person’s real words and the random noises that just sound like words?” Moon agreed, “You have to be very careful. We record the sessions and get consistency in what people hear.” I persisted: “Consistency, as in what, 95 percent, 51 percent?” “A lot,” Moon rejoined.

That evening in my keynote address I explained how “priming” the brain to see or hear something increases the likelihood that the percepts will obey the concepts. I played a part of Led Zeppelin’s Stairway to Heaven backwards, in which one can hear an occasional “Satan,” and then played it again after priming their brains with the alleged lyrics on the screen. The auditory data jumped off the visual cues (the funniest being “there was a little toolshed where he made us suffer, sad Satan”—see it in my lecture “Skepticism 101” at www.skeptic.com). I also played a number of auditory illusions produced by psychologist Diana Deutsch of the University of California, San Diego (http://deutsch.ucsd.edu/), in which a repetitive tape loop of a two-syllable word educes different words and phrases in different people’s minds. These are examples of patternicity, the tendency to find meaningful patterns in meaningless noise (a concept I introduced in my December 2008 column), and the next day I put it to the test when Moon gave me a personal demo. With the Telephone to the Dead squawking away, I tried to connect to my deceased father and mother, asking for any “validation” of a connection—name, cause of death ... anything. I coaxed and cajoled. Nothing. Moon asked Tyler to intervene. Nothing. Moon said he heard something, but when I pressed him he came up with nothing. I willingly suspended my disbelief in hopes of talking to my parents, whom I miss dearly. Nothing. I searched for any pattern I might find. Nothing.

And that, I’m afraid, is my assessment of the paranormal. Nothing.

Predicting risk taking

From Gianotti et al., who performed EEG measurements on forty right-handed female students at the Univ. of Zurich:

Human risk taking is characterized by a large amount of individual heterogeneity. In this study, we applied resting-state electroencephalography, which captures stable individual differences in neural activity, before subjects performed a risk-taking task. Using a source-localization technique, we found that the baseline cortical activity in the right prefrontal cortex predicts individual risk-taking behavior. Individuals with higher baseline cortical activity in this brain area display more risk aversion than do other individuals. This finding demonstrates that neural characteristics that are stable over time can predict a highly complex behavior such as risk-taking behavior and furthermore suggests that hypoactivity in the right prefrontal cortex might serve as a dispositional indicator of lower regulatory abilities, which is expressed in greater risk-taking behavior.

Thursday, January 22, 2009

Some clarity on alternative therapies and medical science

Mindblog reader Ian has pointed me to this essay on alternative medicine and new age spirituality by Bruce Charlton, at the University of Newcastle upon Tyne. His website contains other interesting bits of writing. He paints what I think should be a useful and clear distinction:

I would define alternative therapies in terms of them having non-scientific explanations. In so far as a therapy does have a biological explanation, I would regard that therapy as simply part of orthodox medicine. The crucial difference between orthodox and alternative therapies is therefore that alternative medical systems have non-scientific explanations based on spiritual, mystical, legendary or otherwise intuitively-appealing insights...I am broadly supportive of alternative and complementary therapies because I think that overall they do a great deal of good for a large number of people. But the kind of good they do is psychological and spiritual; not medical. They are about making people feel better (‘healing’) not mending their dysfunctional brains and bodies (‘curing’). Alternative therapies certainly are not a part of medical science. So, on the one hand, I would like to see alternative therapies thrive and spread, and on the other hand they should drop all their pretensions to ‘scientific’ validity. In future, alternative medicine should explicitly become part of New Age spirituality, and thereby clearly be differentiated from orthodox medicine and biological science.
He argues against the relevance of randomized trials to test alternative therapies:
...when randomised trials are used in alternative medicine, the usual process of therapeutic development is turned on-its-head. Instead of coming at the end of a long process of scientific evaluation, randomized trials are placed at the beginning of evaluation, and are indeed expected to be the only form of scientific evaluation – with randomization used in isolation with no possibility for cross-checking using other scientific methods...The problem is not so much that alternative therapy systems are scientifically primitive; it is that alternative systems are not scientific at all. By definition they do not have scientifically-grounded explanations. When the constraints of randomized trials are properly understood, it becomes clear that 'positive' trials in alternative medicine are irrelevant.
His summary:
Orthodox medicine is based on scientific theories and is properly characterized by objective evaluation criteria and formal professional structures of education and certification. Alternative healing deploys a wide range of intuitively-appealing but non-scientific explanations, and constitutes a consumer-dominated marketplace of ideas and therapies which are personally-evaluated by the client...Orthodox medicine focuses on curing disease and promoting health. But alternative therapies should be based on promoting well-being and personal fulfillment. To do this they need to be able freely to deploy poetic explanations and charismatic healers as part of the wide and growing practice of New Age spirituality.

Prosopagnosia due to reduced cortical connectivity

Prosopagnosics have impaired face recognition, but make relatively normal responses to face stimuli in core brain regions for face recognition. Thomas et. al find that it is the connectivity among these regions that is being disrupted in the disorder:

Using diffusion tensor imaging and tractography, we found that a disruption in structural connectivity in ventral occipito-temporal cortex may be the neurobiological basis for the lifelong impairment in face recognition that is experienced by individuals who suffer from congenital prosopagnosia. Our findings suggest that white-matter fibers in ventral occipito-temporal cortex support the integrated function of a distributed cortical network that subserves normal face processing.

Wednesday, January 21, 2009

Sex, sweat and your brain

From Zou and Chen, showing that two areas of women's brains respond to chemical signals in the sweat of sexually aroused men. Their edited abstract, and a figure:

Chemosensory communication of affect and motivation is ubiquitous among animals. In humans, emotional expressions are naturally associated with faces and voices. Whether chemical signals play a role as well has hardly been addressed. Here, we use functional magnetic resonance imaging to show that the right orbitofrontal cortex, right fusiform cortex, and right hypothalamus respond to airborne natural human sexual sweat (distinguishing it from neutral sweat, and a nonsocial control), indicating that this particular chemosensory compound is encoded holistically in the brain. Interestingly, with the exception of hypothalamus, neither the OFC nor the fusiform region is implicated in sexual motivation and behavior. Hence, our results implied that the chemosensory information from natural human sexual sweat was encoded more holistically in the brain rather than specifically for its sexual quality. Our findings provide neural evidence that socioemotional meanings, including the sexual ones, are conveyed in the human sweat.

Figure - Brain responses to social chemosensory compounds. a, Coronal view showing an activated area in the right orbitofrontal cortex. d. Sagittal view showing an activated region in the right fusiform gyrus.

(I might as well also repeat this link from a post several days ago, on the debate raging over MRI studies of social cognition that has been started off by a paper titled "Voodoo correlations in social neuroscience".)

Why we hiccup.

An article by Neil Shubin in the January Scientific American notes how a number of evolutionary hand-me-downs inherited from fish and tadpoles have left us with hernias, hiccups and other maladies. I thought this bit on why we hiccup was fascinating: it is because we once were tadpoles.

A spasm of the muscles in the throat and chest causes a hiccup. The characteristic “hic” sound results when we sharply inspire air while the epiglottis, a flap of soft tissue at the back of the throat, closes. All these movements are completely involuntary; we “hic” without any thought on our part. Hiccups occur for many reasons: we eat too fast or too much; even more severe conditions, such as tumors in the chest area, can bring them on. Hiccups reveal at least two layers of our history: one shared with fish, another with amphibians, according to one well-supported hypothesis. We inherited the major nerves we use in breathing from fish. One set of nerves, the phrenic, extends from the base of the skull and travels through the chest cavity and the diaphragm, among other places. This tortuous course creates problems; anything that interrupts the path of these nerves along their length can interfere with our ability to breathe. Irritation of these nerves can even be a cause of hiccups. A more rational design of the human body would have the nerves traveling not from the neck but from a spot nearer to the diaphragm. Unluckily, we became heir to this design from fishy ancestors with gills closer to the neck, not a diaphragm well below it. If the strange pathway of the nerves is a product of our fish origin, the hiccup itself may have arisen from the past we share with amphibians. It turns out that the characteristic pattern of muscle and nerve activity of hiccups occurs naturally in other creatures. And not just any creatures. More specifically, they turn up in tadpoles that use both lungs and gills to breathe. When tadpoles use their gills, they have a problem— they need to pump water into their mouth and throat and then across the gills, but they need to keep this water from entering their lungs. So what do they do? They shut the glottis to close off the breathing tube, while sharply inspiring. In essence, they breathe with their gills using an extended form of hiccup. (click on figure to enlarge it).

Tuesday, January 20, 2009

Species conservation - how being helpful hurts

Cornelia Dean makes note of a fact I had not thought much about. Conservation regulations that specify the minimum size of individuals that can be harvested, whether they be fish, bighorn sheep, or ginseng plants, increase the rate of evolution to favor smaller individuals that reproduce at an earlier age. This works against species health. Humans are harvesting mature adults, whereas natural predators would target smaller or weaker (old) individuals. Rates of evolutionary change are three times higher in species subject to “harvest selection” than in other species. Here is the abstract of Darimont et al.'s work.

Oxytocin makes a face in memory familiar

It is known that men treated with oxytocin perform better in inferring affective state from the eye region of human faces. Oxytocin also increases social behaviors like trust. Rimmele at al. show now that oxytocin delivered by a commercially available nasal spray (Syntocinon Spray from Novartis) selectively enhances memory encoding of faces in humans, but not of nonsocial stimuli. Here is their abstract:

Social recognition is the basis of all social interactions. Here, we show that, in humans, the evolutionarily highly conserved neuropeptide oxytocin, after intranasal administration, specifically improves recognition memory for faces, but not for nonsocial stimuli. With increased oxytocin levels, previously presented faces were more correctly assessed as "known," whereas the ability of recollecting faces was unchanged. This pattern speaks for an immediate and selective effect of the peptide strengthening neuronal systems of social memory.

Monday, January 19, 2009

Brain games for you, coming soon from Mattel

Justin Landwehr and PFSK point us to a concentration game coming from Mattel.

MRI of human social values?

I read something like this by Zahn et. al., and am fascinated at the same time I am wondering what the hell to make of it. (Here, by the way, is a disucssion of the debate raging over MRI studies of social cognition that has been started off by a paper titled "Voodoo correlations in social neuroscience".) My impression is that if you scan the MRI (magnetic resonance brain imaging) literature for all the functions that have been 'correlated with,' for example, the subgenual cingulate (in this case, guilt) or orbitofrontal-insular cortices (indignation, anger) you would find a hopelessly large list. Still, the prospect of stable neural architectures associated with different discrete social emotions is interesting. The authors suggest that social values emerge from coactivation of abstract conceptual representations within the anterior temporal lobe region (aTL, BA38/22), emotional states represented in mesolimbic and basal forebrain regions (hypothalamus, septum, VTA (ventral tegmental area), anterior insula) and emotion–action associations in OFC (orbitofrontal cortex) as well as sequential action outcomes in anterior medial PFC (prefrontal cortex) regions. They provide data...

...supporting a model in which social values draw upon stable representations of conceptual detail within the anterior temporal lobe region (aTL, BA38/22) and context-dependent representations of distinct moral sentiments within fronto-mesolimbic regions. They test a model of integration of the concepts and emotions that form social values in which social values change their emotional quality in a flexible way adapted to the context of agency. They suggest that a separation of stable context-independent representations in the aTL can be flexibly embedded within different contexts of action implementation and emotional qualities as encoded in fronto-limbic circuits to account for our ability to link social values to a wide range of interpersonal and cultural settings

The interdependency of context of actions and emotional evaluation has been a key component of the notion of values proposed by British philosophers during the 18th century. According to this stance, intuitive "moral sentiments" determine whether we perceive a behavior as constituting a virtue or vice and guide our approval or disapproval of that behavior...When we are the agent of an action conforming to our values, we may feel pride, whereas when another person is the agent, we may feel gratitude. On the negative side, when we act counter to our values, we may feel guilt and when another person acts in the same way toward us, we instead feel indignation or anger.
Here is the abstract of the paper:
Social values are composed of social concepts (e.g., "generosity") and context-dependent moral sentiments (e.g., "pride"). The neural basis of this intricate cognitive architecture has not been investigated thus far. Here, we used functional magnetic resonance imaging while subjects imagined their own actions toward another person (self-agency) which either conformed or were counter to a social value and were associated with pride or guilt, respectively. Imagined actions of another person toward the subjects (other-agency) in accordance with or counter to a value were associated with gratitude or indignation/anger. As hypothesized, superior anterior temporal lobe (aTL) activity increased with conceptual detail in all conditions. During self-agency, activity in the anterior ventromedial prefrontal cortex correlated with pride and guilt, whereas activity in the subgenual cingulate solely correlated with guilt. In contrast, indignation/anger activated lateral orbitofrontal-insular cortices. Pride and gratitude additionally evoked mesolimbic and basal forebrain activations. Our results demonstrate that social values emerge from coactivation of stable abstract social conceptual representations in the superior aTL and context-dependent moral sentiments encoded in fronto-mesolimbic regions. This neural architecture may provide the basis of our ability to communicate about the meaning of social values across cultural contexts without limiting our flexibility to adapt their emotional interpretation.

Friday, January 16, 2009

Finger length predicts successful financial trading!

This analysis by Coates et al. is a real hoot. They find that the second-to-fourth digit ratio predicts success among high-frequency financial traders:

Prenatal androgens have important organizing effects on brain development and future behavior. The second-to-fourth digit length ratio (2D:4D) has been proposed as a marker of these prenatal androgen effects, a relatively longer fourth finger indicating higher prenatal androgen exposure. 2D:4D has been shown to predict success in highly competitive sports. Yet, little is known about the effects of prenatal androgens on an economically influential class of competitive risk taking—trading in the financial world. Here, we report the findings of a study conducted in the City of London in which we sampled 2D:4D from a group of male traders engaged in what is variously called “noise” or “high-frequency” trading. We found that 2D:4D predicted the traders' long-term profitability as well as the number of years they remained in the business. 2D:4D also predicted the sensitivity of their profitability to increases both in circulating testosterone and in market volatility. Our results suggest that prenatal androgens increase risk preferences and promote more rapid visuomotor scanning and physical reflexes. The success and longevity of traders exposed to high levels of prenatal androgens further suggests that financial markets may select for biological traits rather than rational expectations.

Insults and joys of old age...

Dwight Garner offers a review of a recent book, "Somewhere towards the end," by former prominent London book editor, 91 year old Diana Athill. ( I regret that I - like many of you, I suspect - read more book reviews than actual books.) Here are some clips that I thought interesting:

A positive aspect of the waning of sex, Ms. Athill says, “was that other things became more interesting.” ... I was surprised that this longtime fiction editor has declared that she has “gone off novels.”...Why? She no longer feels the need to parse the intricacies of human relationships and love affairs, “but I do still want to be fed facts, to be given material which extends the region in which my mind can wander.” ...The elderly, she writes, can find great enjoyment in the company of younger people. But she warns: “One should never, never expect them to want one’s company, or make the kind of claims on them that one makes on a friend of one’s own age. Enjoy whatever they are generous enough to offer, and leave it at that.”
The book ends with her realization:
“There are no lessons to be learnt, no discoveries to be made, no solutions to offer. I find myself left with nothing but a few random thoughts. One of them is that from up here I can look back and see that although a human life is less than the blink of an eyelid in terms of the universe, within its own framework it is amazingly capacious so that it can contain many opposites. One life can contain serenity and tumult, heartbreak and happiness, coldness and warmth, grabbing and giving — and also more particular opposites such as a neurotic conviction that one is a flop and a consciousness of success amounting to smugness.”

Thursday, January 15, 2009

The dead end of current economic models...

Here is a short and sweet statement of the futility of current models of economic recovery and growth, from a letter to the Nature editor from Hervé Philippe, a biochemist at the University of Montreal. It mirrors my own sentiment: that talk of 'restoring economic growth' in the absence of ruthless planning to achieve steady state sustainable energy fluxes on this planet is delusional.

...the prosperity [of Western societies] is mainly based on the use of non-renewable resources and therefore is probably spurious...Several hundred million years were needed to form the fossil energy that will be exhausted during a few hundred years. This is roughly equivalent to spending all one's annual income during the first 30 seconds of a year. In particular, the frenzy to automate processes in order to increase competitiveness leads to rapid exhaustion of available resources, for example through over-fishing or degradation of soils....All current growth-based economic models imply massive use of non-renewable resources and environmental degradation. These models are not sustainable, even in the short term....As early as 160 years ago, John Stuart Mill affirmed that "the richest and most prosperous countries would very soon attain the stationary state" (Principles of Political Economy Longmans, 1848). In contrast to that time, when resources were being used up at a rate that was several orders of magnitude slower than today, a phase of economic degrowth is necessary before a stationary state can be reached. It would be a major achievement of economics to achieve such a degrowth without social and political disasters.

A neurosciences site feed aggregator

I get an email a few weeks ago saying that Deric's MindBlog had been added to an "online magazine rack" called Alltop. If you are in the mood for even more sensory overload, you might check it out. (Later note: in the comment below, Justin points out that Alltop is a creation of entrepreneur Guy Kawasaki, a site

...that provides “all the top” stories for forty of the most popular topics on the Web. The headlines and first paragraph of the five most recent stories from forty to eighty sources for each topic are displayed. Alltop stories are refreshed approximately every ten minutes.

A good metaphor is that Alltop is an "online magazine rack" that displays the news from the top publications and blogs. Our goal is to satisfy the information needs of the 99% of Internet users who will never use an RSS feed reader or create a custom page. Think of it as "aggregation without the aggravation.”

Cartoon instructions for some neat sensory illusions.

This link is sent by a reader. Simple cartoon instructions from the Boston Globe for how you can cause changes in your visual images or body image, either by yourself or with a friend.

Wednesday, January 14, 2009

The neuroscience of love

Larry Young offers this latest installment in Nature's "Being Human" series on a topic I have mentioned in a number of previous posts. He notes that animal studies that demystified emotions such as fear and anxiety are beginning to illuminate the mental states associated with love. This has implications for the nature of human sexuality — and could even lead to drugs to enhance or diminish our love for another. Tierney comments (the graphic is from his article) on Young's essay , suggesting that

...the really good news, as I see it, is that we might reverse-engineer an anti-love potion, a vaccine preventing you from making an infatuated ass of yourself.
Here are some clips from Young:
We are not alone in being able to form intense and enduring social ties. Take the mother–infant bond. Whether or not the emotional connection between a ewe and her lamb, or a female macaque and her offspring, is qualitatively similar to human motherly love, it is highly likely that these relationships share evolutionarily conserved brain mechanisms. In humans, rats and sheep, the hormone oxytocin is released during labour, delivery and nursing. In ewes, an infusion of oxytocin into the brain results in rapid bonding with a foreign lamb...There is intriguing overlap between the brain areas involved in vole pair bonding and those associated with human love. Dopamine-related reward regions of the human brain are active in mothers viewing images of their child. Similar activation patterns are seen in people looking at photographs of their lovers.

Pair bonding in males involves similar brain circuitry to that in females, but different neurochemical pathways. In male prairie voles, for example, vasopressin — a hormone related to oxytocin — stimulates pair bonding, aggression towards potential rivals, and paternal instincts, such as grooming offspring in the nest. Variation in a regulatory region of the vasopressin receptor gene, avpr1a, predicts the likelihood that a male vole will bond with a female.

Similarly, in humans, different forms of the AVPR1A gene are associated with variation in pair bonding and relationship quality. A recent study shows that men with a particular AVPR1A variant are twice as likely as men without it to remain unmarried, or when married, twice as likely to report a recent crisis in their marriage. Spouses of men with the variant also express more dissatisfaction in their relationships than do those of men lacking it. For both voles and humans, AVPR1A genetic polymorphisms predict how much vasopressin receptor is expressed in the brain.

The view of love as an emergent property of a cocktail of ancient neuropeptides and neurotransmitters raises important issues for society. For one thing, drugs that manipulate brain systems at whim to enhance or diminish our love for another may not be far away. Experiments have shown that a nasal squirt of oxytocin enhances trust and tunes people into others' emotions. Internet entrepreneurs are already marketing products such as Enhanced Liquid Trust, a cologne-like mixture of oxytocin and pheromones "designed to boost the dating and relationship area of your life". Although such products are unlikely to do anything other than boost users' confidence, studies are under way in Australia to determine whether an oxytocin spray might aid traditional marital therapy.

We don't yet know whether the drugs commonly used to treat disorders from depression to sexual dysfunction affect people's relationships by altering neurochemistry. But both Prozac and Viagra influence the oxytocin system. The quality of patients' relationships should be included in the list of variables assessed in controlled psychiatric drug studies.


Followup on 'Reinventing the sacred'....

I relay here (with permission) an email comment on the 'Reinventing the Sacred' post and suggest that you look at several other thoughtful comments at the end of that post.

Perhaps philosophy has something to offer the 'hard core materialist'. I recently read "Illness" by Havi Carel which I must say was a truly moving experience. Meditations on death and meaning using the authors knowledge of Greek Philosophy and Phenomenology enabled her to 'live well' with illness. This is something that a naturalistic bioscience approach would have trouble with?

You might like the thoughts of the former Bishop of Edinburgh Richard Holloway "Looking in the distance -the human search for meaning" is one of his excellent books. Holloway, who is now in charge of the Arts Council,sees religion as poetry and metaphor rather than a competition with science which seeks to search for 'material' truth.....Most people appear to need a bit of both and there does seem a universal need for spirituality and engagement-which does not have to be gained by participation in organized religion. Some of the offshoots of immersion in religious practices and spiritual disciplines do appear to have material benefit too (in terms of health and cohesion of community) but this is another discussion perhaps.

Tuesday, January 13, 2009

Bees on cocaine...

Here is an item that falls into the 'random curious stuff' category of this blog's subheading:

A common speculation is that the cocaine that triggers reward pathways in our brains evolved as an insecticide that protects the coca plant. Barron et al. have now found a reward effect in bees. By examining the honey bee dance--the means by which bees signal the availability of resources to their hive-mates--they found that dosing the bees with cocaine increased both the likelihood and rate of dance after foraging; furthermore, the bees exhibited behavior consistent with a withdrawal effect when the drug was withheld after chronic treatment. They suggest that the response to the drug may be similar in humans and bees. Here is their abstract:

The role of cocaine as an addictive drug of abuse in human society is hard to reconcile with its ecological role as a natural insecticide and plant-protective compound, preventing herbivory of coca plants (Erythroxylum spp.). This paradox is often explained by proposing a fundamental difference in mammalian and invertebrate responses to cocaine, but here we show effects of cocaine on honey bees (Apis mellifera L.) that parallel human responses. Forager honey bees perform symbolic dances to advertise the location and value of floral resources to their nest mates. Treatment with a low dose of cocaine increased the likelihood and rate of bees dancing after foraging but did not otherwise increase locomotor activity. This is consistent with cocaine causing forager bees to overestimate the value of the floral resources they collected. Further, cessation of chronic cocaine treatment caused a withdrawal-like response. These similarities likely occur because in both insects and mammals the biogenic amine neuromodulator systems disrupted by cocaine perform similar roles as modulators of reward and motor systems. Given these analogous responses to cocaine in insects and mammals, we propose an alternative solution to the paradox of cocaine reinforcement. Ecologically, cocaine is an effective plant defence compound via disruption of herbivore motor control but, because the neurochemical systems targeted by cocaine also modulate reward processing, the reinforcing properties of cocaine occur as a `side effect'.

MRI in the courtroom as witness on pain?

Greg Miller notes, in his report on a Stanford Law School Event, that because pain pathways in the brain are better understood than those underlying lying, pain detection is more likely to be the first fMRI application to find widespread use in the courtroom.

...pain is an issue in about half of all tort cases, which include personal injury cases. Billions of dollars are at stake. Yet people with real pain are sometimes unable to prove it, and malingerers sometimes win cases by faking it...However, using fMRI as a painometer isn't straightforward. For starters, said Katja Wiech, a cognitive neuroscientist at University College London, pain sensitivity varies considerably from one person to the next. It's also influenced by psychological factors such as anxiety (which tends to make pain worse) and attention (focusing on pain makes it worse; distractions take the edge off). Such influences also show up in fMRI scans, Wiech said. Moreover, she and others noted that several studies have found broad overlap in the brain regions activated by real and imagined pain--something that could be exploited by plaintiffs with bogus claims.

A. Vania Apkarian, a neuroscientist at Northwestern University in Evanston, Illinois, was more optimistic. His group has found that activity in the medial prefrontal cortex and the right insula correlates well with pain intensity and the duration of chronic pain, respectively, in people with chronic back pain. "This is an objective measure of pain in these patients," Apkarian said. Based on these and other findings, he predicted that fMRI will be courtroom-ready sooner than others had suggested. "Maybe not in 2008, maybe in 2012," he said. "It's inevitable."

Apkarian's data looked promising to several legal experts in attendance. "You scientists care more about causation than we do in the law," said Stanford law professor Henry "Hank" Greely. "If the correlation is high enough, … we would see that as a useful tool." Indeed, Greely and others noted, even if fMRI can't provide a perfectly objective measure of pain, it may still be better than the alternatives. "We let people get on the stand … and say all kinds of things that may or may not be true," said William Fletcher, a judge on the U.S. Court of Appeals for the Ninth Circuit.

Monday, January 12, 2009

Sneakiness and brain size

I have a huge backlog of potential mindblog posts which haven't yet made it into the two posts per day routine I have set up. They are interesting, but keep getting pushed back in the queue by newer material that is appearing. Here is an engaging piece from Natalie Angier, motivated perhaps by the Madoff scandal, on deception in humans and other animals - the 'lying in everyday life' that lubricates human and animal social interactions.

...[there is] a direct relationship between sneakiness and brain size. The larger the average volume of a primate species’ neocortex — the newest, “highest” region of the brain — the greater the chance that the monkey or ape would pull a stunt like this one described in The New Scientist: a young baboon being chased by an enraged mother intent on punishment suddenly stopped in midpursuit, stood up and began scanning the horizon intently, an act that conveniently distracted the entire baboon troop into preparing for nonexistent intruders.

...researchers found that the college students told an average of two lies a day, community members one a day, and that most of the lies fell into the minor fib category...There is a counterintuitive motivation not to detect lies, or we would have become much better at it...you may not really want to know that the dinner you just cooked stinks, or even that your spouse is cheating on you.
The article notes a further number of interesting deceptive behaviors in humans and other animals.

We infer rather than perceive the moment we decided to act.

Banks and Isham do a further followup (see this post for a previous followup) on the famous Libet experiment that showed that the reported time of a decision to perform a simple action is at least 300 ms after the onset of brain activity that normally precedes the action. They propose that the reported time is not uniquely determined by any generator of the readiness potential (the commonly head view), but rather is the time participants select on the basis of available cues, chief among them being the apparent time of response. From their abstract:

In Experiment 1, we presented deceptive feedback (an auditory beep) 5 to 60 ms after the action to signify a movement time later than the actual movement. The reported time of decision moved forward in time linearly with the delay in feedback, and came after the muscular initiation of the response at all but the 5-ms delay. In Experiment 2, participants viewed their hand with and without a 120-ms video delay, and gave a time of decision 44 ms later with than without the delay. We conclude that participants' report of their decision time is largely inferred from the apparent time of response. The perception of a hypothetical brain event prior to the response could have, at most, a small influence.

Friday, January 09, 2009

Anxiety correlates with diminished prefrontal control of attention.

Sonia J Bishop, in an article in Nature Neuroscience, makes the case that trait anxiety (i.e. stable ongoing anxiety tendencies not related to a specific sudden threat) may be characterized by impaired recruitment of prefrontal mechanisms that are critical to the active control of attention when the task at hand does not fully govern the allocation of attention. She proposes that this deficit does not arise as a result of current or state levels of anxiety, but instead reflects an underlying trait characteristic that influences attentional processing regardless of the presence or absence of threat-related stimuli. This may interact with state anxiety influences on subcortical threat detection mechanisms to account for the threat-related attentional biases associated with clinical anxiety. It may also account for observations that anxious individuals show deficits across a range of non-affective tasks that place demands on attentional or cognitive control. Here is her abstract:

Many neurocognitive models of anxiety emphasize the importance of a hyper-responsive threat-detection system centered on the amygdala, with recent accounts incorporating a role for prefrontal mechanisms in regulating attention to threat. Here we investigated whether trait anxiety is associated with a much broader dysregulation of attentional control. Volunteers performed a response-conflict task under conditions that posed high or low demands on attention. High trait-anxious individuals showed reduced prefrontal activity and slower target identification in response to processing competition when the task did not fully occupy attentional resources. The relationship between trait anxiety and prefrontal recruitment remained after controlling for state anxiety. These findings indicate that trait anxiety is linked to impoverished recruitment of prefrontal attentional control mechanisms to inhibit distractor processing even when threat-related stimuli are absent. Notably, this deficit was observed when ongoing task-related demands on attention were low, potentially explaining the day-to-day difficulties in concentration that are associated with clinical anxiety.

How do you feel — now? The anterior insula and human awareness

In a perspectives article in Nature Neuroscience Bud Craig proposes that the anterior insula plays a fundamental role in human awareness (if you simply enter 'anterior insula' in google images you can see depictions of the structures for yourself, or see the figure below). Here is his abstract, followed by a description of the structure and then his model for the involvement of the insula in awareness:

The anterior insular cortex (AIC) is implicated in a wide range of conditions and behaviours, from bowel distension and orgasm, to cigarette craving and maternal love, to decision making and sudden insight. Its function in the re-representation of interoception offers one possible basis for its involvement in all subjective feelings. New findings suggest a fundamental role for the AIC (and the von Economo neurons it contains) in awareness, and thus it needs to be considered as a potential neural correlate of consciousness.

A photograph of the left insular cortex of a human patient. The human insular cortex is a distinct but hidden lobe of the brain. It is disproportionately (approx30%) enlarged in the human relative to the macaque monkey. It has 5–7 oblique gyri, but its morphology is quite variable, even between the two sides. Primary interoceptive representations are located in the dorsal posterior insula and re-represented in a polymodal integrative zone in the mid-insula and again in the anterior insular cortex (AIC). The primary interoceptive, gustatory and vagal representations extend to the anterior limit of the insula in macaques but only to the middle of the insula in humans, which suggests that the AIC of humans has no equivalent in the monkey. The most anterior and ventral (inferior) portion of the human insula that adjoins the frontal operculum is probably the most recently evolved, because this part (as well as the anterior cingulate cortex) contains von Economo neurons. as, anterior short insular gyrus; al, anterior long insular gyrus; ac, accessory gyrus; APS, anterior peri-insular sulcus; H, Heschl's gyrus; IPS, inferior peri-insular sulcus; ms, middle short insular gyrus; ps, posterior short insular gyrus; pl, posterior long insular gyrus; SPS, superior peri-insular sulcus. Photograph is courtesy of Professor Thomas P. Naidich, Mount Sinai Medical Center, New York.

Cartoons illustrating features of the proposed structural model of awareness. a | The posited integration of salient activity, progressing from the posterior insula (left) to the anterior insula (right). The primary interoceptive representations of feelings from the body provide a somatotopic foundation that is anchored by the associated homeostatic effects on cardiorespiratory function, as indicated by the focus of the colours in the chest. The integration successively includes homeostatic, environmental, hedonic, motivational, social and cognitive activity to produce a 'global emotional moment', which represents the sentient self at one moment of time. b | The top cartoon shows how a series of global emotional moments can produce a cinemascopic 'image' of the sentient self across time. The lower cartoon shows how the proposed model can produce a subjective dilation of time during a period of high emotional salience, when global emotional moments are rapidly 'filled up'. ACC, anterior cingulate cortex; DLPFC, dorsolateral prefrontal cortex; VMPFC, ventromedial prefrontal cortex.

Thursday, January 08, 2009

A trick for appreciating the present moment

How natural or easy is it to relish our daily life experiences? Every self-help book you pick up says we should "stop and smell the roses." Kurtz looks at temporal scarcity as a motivator. His abstract:

Both psychological research and conventional wisdom suggest that it can be difficult to attend to and derive enjoyment from the pleasant things in life. The present study examined whether focusing on the imminent ending of a positive life experience can lead to increased enjoyment. A temporal distance manipulation was used to make college graduation seem more or less close at hand. Twice a week over the course of 2 weeks, college students were told to write about their college life, with graduation being framed as either very close or very far off. As predicted, thinking about graduation as being close led to a significant increase in college-related behaviors and subjective well-being over the course of the study. The present research provides support for the counterintuitive hypothesis that thinking about an experience's ending can enhance one's present enjoyment of it.

Unconscious threats increase moral affirmations

Proulx and Heine probe the "meaning-maintenance model," that proposes that whenever an individual's mental representations of expected associations (e.g., scripts, schemas, paradigms) are violated by unexpected experiences, this provokes an effort to regain a sense of meaning. The abstract, followed by a bit of explanation:

The meaning-maintenance model posits that threats to schemas lead people to affirm unrelated schemas. In two studies testing this hypothesis, participants who were presented with a perceptual anomaly (viz., the experimenter was switched without participants consciously noticing) demonstrated greater affirmation of moral beliefs compared with participants in a control condition. Another study investigated whether the schema affirmation was prompted by unconscious arousal. Participants witnessed the changing experimenter and then consumed a placebo. Those who were informed that the placebo caused side effects of arousal did not show the moral-belief affirmation observed in the previous studies, as they misattributed their arousal to the placebo. In contrast, those who were not informed of such side effects demonstrated moral-belief affirmation. The results demonstrate the functional interchangeability of different meaning frameworks, and highlight the role of unconscious arousal in prompting people to seek alternative schemas in the face of a meaning threat.
A bit more explanation:
In the changing-experimenter condition, while participants answered questions about entertainment, the female research assistant conducting the experiment was surreptitiously switched with another, identically dressed female experimenter. The first experimenter went to a filing cabinet to retrieve the next questionnaire, and after opening the filing cabinet, she stepped back and was replaced by the second experimenter, who shut the cabinet and continued the experiment (a video of the change can be viewed on the Web at http://www.psych.ubc.ca/~heine/MMMSwitch.wmv). In the mortality-salience condition, participants completed a standard mortality-salience manipulation by answering two questions about their own death. Previous studies have demonstrated that reminding participants of their eventual death provokes compensatory affirmation of alternative meaning frameworks. The mortality-salience condition was included to compare its results with those of our changing-experimenter condition.

To test affirmation of moral beliefs, subjects read a hypothetical report about the arrest of a prostitute and were asked to set a bond for the prostitute as if they were a judge reviewing the case. The rationale for this latter measure is that people are motivated to maintain their cultural worldview and will seek to punish individuals who act in ways that are inconsistent with that worldview. Participants in the changing-experimenter and mortality-salience conditions set a higher bond than did participants in the control condition

Wednesday, January 07, 2009

Reinventing the sacred

Those of us who are hard core materialists and have no use for explanations of the natural order provided by any of the main religions do have the problem of aridity. Being an atheistic secularist is not as warm and cuddly as the warm blanket of religious certainty and the social support provided by some religious settings. Even though I agree with sentiments in such recent books as "The God Delusion", "The end of Faith" and "God is not Great" I wish they could come forward with more compelling alternatives for maintaining the robustness of our evolved psychology.

Stuart Kauffman, the guy who has done a number of books on chaos, self organization, and emergence theory, has stepped forward to offer a new book, "Reinventing the Sacred," in which he suggests that we turn our reverence towards a "natural God" seen not as a supernatural Creator but as the natural creativity in the universe - a universe in which the unpredictable emergence of novelty is a daily occurrence.

"If we reinvent the sacred to mean the wonder of the creativity in the universe, biosphere, human history, and culture, are we not inevitably invited to honor all of life and the planet that sustains it?"
Noble sentiments, indeed, but still not developed into a form accessible or useful to the vast majority of humans who crave certainly and structure in their lives. "Unpredictable emergence of novelty" is not exactly a warm blanket. I wish I had any better ideas.....

Excuses: both ego defense and self sabotage

Benedict Cary has a nice piece in the Tuesday Science NYTimes section

...genuine excuse artisans — and there are millions of them — don’t wait until after choking to practice their craft. They hobble themselves, in earnest, before pursuing a goal or delivering a performance. Their excuses come preattached: I never went to class. I was hung over at the interview. I had no idea what the college application required...The urge goes well beyond a mere lowering of expectations, and it has more to do with protecting self-image than with psychological conflicts rooted in early development, in the Freudian sense...As a short-term strategy, self-handicapping is often no more than an exercise in self-delusion. Studies of college students have found that habitual handicappers — who skip a lot of classes; who miss deadlines; who don’t buy the textbook — tend to rate themselves in the top 10 percent of the class, though their grades slouch between C and D...The important thing for some is, no matter the method, to avoid considering the alternative explanation...as in the Marlon Brando line from "On the Waterfront": "I coulda been a contender."

Tuesday, January 06, 2009

Ramachandran on qualia and the self.

His bottom line, in an essay in Edge, is that the Qualia problem (how can a martian that knows every physical wiring detail of my seeing red actually have my experience of red) is a pseudo-problem, like two sides of a Moebius strip that look utterly different from our ant-like perspective but are in reality a single surface. From his essay:

The problem of self, on the other hand, is an empirical one that can be solved—or at least explored to its very limit—by science. If and when we do it will be a turning point in the history of science. Neurological conditions have shown that the self is not the monolithic entity it believes itself to be. It seems to consist of many components each of which can be studied individually, and the notion of one unitary self may well be an illusion. (But if so we need to ask how the illusion arises; was it an adaptation acquired through natural selection?)
Ramachandran then goes on to describe the fascinating variations in our sense of self that can be correlated with brain changes. In a previous essay on mirror neurons he
...speculated that these neurons can not only help simulate other people's behavior but can be turned "inward"—as it were—to create second-order representations or metarepresentations of your own earlier brain processes. This could be the neural basis of introspection, and of the reciprocity of self awareness and other awareness. There is obviously a chicken-or-egg question here as to which evolved first, but that is tangential to my main argument.... The main point is that the two co-evolved, mutually enriching each other to create the mature representation of self that characterizes modern humans. Our ordinary language illustrates this, as when we say "I feel a bit self conscious", when I really mean that I am conscious of others being conscious of me. Or when I speak of being self critical or experiencing "self-pity". (A chimp could—arguably—feel pity for a begging chimp, but I doubt whether it would ever experience self-pity.)

I also suggest that although these neurons initially emerged in our ancestors to adopt another's allocentric visual point of view, they evolved further in humans to enable the adoption of another's metaphorical point of view. ("I see it from his point of view" etc.) This, too, might have been a turning point in evolution although how it might have occurred is deeply puzzling.

Aging - Memory decline, sugar control, and emotional memories

Great.....now I learn another way in which my aging brain can fail to remember - the worsening of glucose regulation with aging permits more glucose spikes which reduce blood flow to the dentate gyrus in our hippocampus (required for new memory formation). Perhaps on the more positive side, memories carry less emotion in older people, apparently because their processing moves towards frontal and away from limbic areas.

Monday, January 05, 2009

Get religious to improve self control?

Here is a curious piece by John Tierney noting the work of Michael McCullouch, who provides evidence that religiosity correlates with higher self-control among adults.

“Brain-scan studies have shown that when people pray or meditate, there’s a lot of activity in two parts of brain that are important for self-regulation and control of attention and emotion,” he said. “The rituals that religions have been encouraging for thousands of years seem to be a kind of anaerobic workout for self-control.”

In a study published by the University of Maryland in 2003, students who were subliminally exposed to religious words (like God, prayer or bible) were slower to recognize words associated with temptations (like drugs or premarital sex). Conversely, when they were primed with the temptation words, they were quicker to recognize the religious words.
What should a heathen like myself do?
Dr. McCullough’s advice is to try replicating some of the religious mechanisms that seem to improve self-control, like private meditation or public involvement with an organization that has strong ideals.

Cleanliness reduces the severity of moral judgements.

From Schnall et al. at the Univ. of Plymouth. Here is their abstract, followed by a bit of explanation:

Theories of moral judgment have long emphasized reasoning and conscious thought while downplaying the role of intuitive and contextual influences. However, recent research has demonstrated that incidental feelings of disgust can influence moral judgments and make them more severe. This study involved two experiments demonstrating that the reverse effect can occur when the notion of physical purity is made salient, thus making moral judgments less severe. After having the cognitive concept of cleanliness activated (Experiment 1) or after physically cleansing themselves after experiencing disgust (Experiment 2), participants found certain moral actions to be less wrong than did participants who had not been exposed to a cleanliness manipulation. The findings support the idea that moral judgment can be driven by intuitive processes, rather than deliberate reasoning. One of those intuitions appears to be physical purity, because it has a strong connection to moral purity.

[In experiment 1 two different groups of participants look at lists of scrambled words before being asked to rate the wrongness of six different moral dilemmas. Half of the words in one of the lists related to the theme of cleanliness and purity (e.g., pure, washed, clean, immaculate, pristine), while the other list contained neutral words. In experiment 2 participants were given an opportunity to physically cleanse themselves after experiencing disgust (a physically disgusting scene from a film).]

Friday, January 02, 2009

Heaven for the Godless?

A piece from Charles M. Blow:

In June, the Pew Forum on Religion and Public Life published a controversial survey in which 70 percent of Americans said that they believed religions other than theirs could lead to eternal life...This threw evangelicals into a tizzy. After all, the Bible makes it clear that heaven is a velvet-roped V.I.P. area reserved for Christians. Jesus said so: “I am the way, the truth and the life: no man cometh unto the Father, but by me.” But the survey suggested that Americans just weren’t buying that...The evangelicals complained that people must not have understood the question. The respondents couldn’t actually believe what they were saying, could they?

So in August, Pew asked the question again. (They released the results last week.) Sixty-five percent of respondents said — again — that other religions could lead to eternal life. But this time, to clear up any confusion, Pew asked them to specify which religions. The respondents essentially said all of them...And they didn’t stop there. Nearly half also thought that atheists could go to heaven — dragged there kicking and screaming, no doubt — and most thought that people with no religious faith also could go.

What on earth does this mean?

One very plausible explanation is that Americans just want good things to come to good people, regardless of their faith.

Rapid perceptual switching...

Jackson et al. examine contradictory perceptions while viewing biological versus moving ambiguous structures. (Try this movie of an ambiguous rotating walker, a figure that randomly alternates between walking in clockwise (CW) and counter-clockwise (CCW) directions.) Percept durations with a light point rotating walker are shorter than for a standard light point walker.

Thursday, January 01, 2009

Brain lesions and sprituality

Johnstone and Glass note a correlation between increased spirituality and right parietal lobe lesions, more clear than previously noted correlations with left temporal lobe activity. They suggest this might arise from decreased awareness of the self (leading to sense of transcendence), while reports of spirituality and increased activity of the left temporal lobe might be associated with the experience of specific religious archetypes (religious figures and symbols). (If you click on 'religion' in the left column under 'selected blog categories' you will note a number of differing observations on correlations between spirituality and brain activity.)

Recent research suggests that spiritual experiences are related to increased physiological activity of the frontal and temporal lobes and decreased activity of the right parietal lobe. The current study determined if similar relationships exist between self-reported spirituality and neuropsychological abilities associated with those cerebral structures for persons with traumatic brain injury (TBI). Participants included 26 adults with TBI referred for neuropsychological assessment. Measures included the Core Index of Spirituality (INSPIRIT); neuropsychological indices of cerebral structures: temporal lobes (Wechsler Memory Scale-III), right parietal lobe (Judgment of Line Orientation), and frontal lobes (Trail Making Test, Controlled Oral Word Association Test). As hypothesized, spirituality was significantly negatively correlated with a measure of right parietal lobe functioning and positively correlated (nonsignificantly) with measures of left temporal lobe functioning. Contrary to hypotheses, correlations between spirituality and measures of frontal lobe functioning were zero or negative (and nonsignificant). The data support a neuropsychological model that proposes that spiritual experiences are related to decreased activity of the right parietal lobe, which may be associated with decreased awareness of the self (transcendence) and increased activity of the left temporal lobe, which may be associated with the experience of specific religious archetypes (religious figures and symbols).

Living the Off-Label Life

Further comments on cognition enhancing drugs from Warner, commenting on the Nature essay I mentioned previously.