Thursday, April 16, 2015

Positive and negative emotions - valence is not value

Having done several recent posts on positive emotions,  and given the continuing rise of the "Be Happy" industry with its Be Happy Apps, I thought it appropriate to pass on this pithy and appropriate critique by June Gruber, of the idea that happiness is always good, sadness is always bad:
One idea in the study of emotion and its impact on psychological health is overdue for retirement: that negative emotions (like sadness or fear) are inherently bad or maladaptive for our psychological well-being, and positive emotions (like happiness or joy) are inherently good or adaptive. Such value judgments are to be understood, within the framework of affective science, as depending on whether an emotion impedes or fosters a person's ability to pursue goals, attain resources, and function effectively within society. Claims of the sort "sadness is inherently bad" or "happiness is inherently good" must be abandoned in light of burgeoning advances in the scientific study of human emotion.
Let's start with negative emotions. Early hedonic theories defined well-being, in part, as the relative absence of negative emotion. Empirically based treatments like cognitive-behavioral therapy also focus heavily on the reduction of negative feelings and moods as part of enhancing well-being. Yet a strong body of scientific work suggests that negative emotions are essential to our psychological well-being. Here are 3 examples. First, from an evolutionary perspective, negative emotions aid in our survival—they provide important clues to threats or problems that need our attention (such as an unhealthy relationship or dangerous situation). Second, negative emotions help us focus: they facilitate more detailed and analytic thinking, reduce stereotypic thinking, enhance eyewitness memory, and promote persistence on challenging cognitive tasks. Third, attempting to thwart or suppress negative emotions—rather than accept and appreciate them—paradoxically backfires and increases feelings of distress and intensifies clinical symptoms of substance abuse, overeating, and even suicidal ideation. Counter to these hedonic theories of well-being, negative emotions are hence not inherently bad for us. Moreover, the relative absence of them predicts poorer psychological adjustment.
Positive emotions have been conceptualized as pleasant or positively valenced states that motivate us to pursue goal-directed behavior. A longstanding scientific tradition has focused on the benefits of positive emotions, ranging from cognitive benefits such as enhanced creativity, social benefits like fostering relationship satisfaction and prosocial behavior, and physical health benefits such as enhanced cardiovascular health. From this work has emerged the assumption—both implicitly and explicitly—that positive emotional states should always be maximized. This has fueled the birth of entire subdisciplines and garnered momentous popular attention. But there's a mounting body of work against the claim that positive emotions are inherently good. First, positive emotions foster more self-focused behavior, including increased selfishness, greater stereotyping of out-group members, increased cheating and dishonesty, and decreased empathic accuracy in some contexts. Second, positive emotions are associated with greater distractibility and impaired performance on detail-oriented cognitive tasks. Third, because positive emotion may promote decreased inhibition it has been associated with greater risk-taking behaviors and mortality rates. Indeed, the presence of positive emotions is not always adaptive and sometimes can impede our well-being and even survival.
We are left to conclude that valence is not value: we cannot infer value judgments about emotions on the basis of their positive or negative valence. There is no intrinsic goodness or badness of an emotion merely because of its positivity or negativity, respectively. Instead, we must refine specific value-based determinants for an emotion's functionality. Towards this end, emerging research highlights critical variables to focus on. Importantly, the context in which an emotion unfolds can determine whether it helps or hinders an individual's goal, or which types of emotion regulatory strategies (reappraising or distracting) will best match the situation. Related, the degree of psychological flexibility someone possesses—including how quickly one can shift emotions or rebound from a stressful situation—promotes critical clinical health outcomes. Likewise, we find that psychological well-being is not entirely determined by the presence of one type or kind of an emotion but rather an ability to experience a rich diversity of both positive and negative emotions. Whether or not an emotion is "good" or "bad" seems to have surprisingly little to do with the emotion itself, but rather how mindfully we ride the ebbs and tides of our rich emotional life.

Wednesday, April 15, 2015

What happens in Vagus - compassion, positive emotion, vagal tone, and respiratory sinus arrhythmia,

The 10th cranial nerve, the vagus nerve, is distinctive to mammals and supports social engagement and nurturing behaviors as well as feeding, digesting, resting, breeding, etc. Its level of activity (tonus, or tension) is reflected in its inhibitory regulation of heartbeat, slowing it during exhalation and increasing it during inhalation. This change is heart rate is called respiratory sinus arrhythmia (RSA). Thus RSA serves as a measure of vagal tone. Dacher Keltner and collaborators have studied the relationship of vagal activity, reflected by RSA, to compassion and other prosocial emotions. I want to pass on the abstract from a preprint that can be downloaded here on studies correlating respiratory sinus arrhythmia with tonic (but not phasic) positive emotionality
Resting respiratory sinus arrhythmia (RSAREST) indexes important aspects of individual differences in emotionality. In the present investigation, we address whether RSAREST is associated with tonic positive or negative emotionality, and whether RSAREST relates to phasic emotional responding to discrete positive emotion-eliciting stimuli. Across an 8-month, multiassessment study of first-year university students (n = 80), individual differences in RSAREST were associated with positive but not negative tonic emotionality, assessed at the level of personality traits, long-term moods, the disposition toward optimism, and baseline reports of current emotional states. RSAREST was not related to increased positive emotion, or stimulusspecific emotion, in response to compassion-, awe-, or pride-inducing stimuli. These findings suggest that resting RSA indexes aspects of a person’s tonic positive emotionality.
Reproducability in these studies may be an issue, because there is an apparent conflict between this abstracts report of no relationship between RSAREST compassion-, awe-, or pride-inducing stimuli and the "increases in RSA during compassion" mentioned in Study 4 of the first link above. I might as well paste in that abstract also:
Compassion is an affective response to another’s suffering and a catalyst of prosocial behavior. In the present studies, we explore the peripheral physiological changes associated with the experience of compassion. Guided by long-standing theoretical claims, we propose that compassion is associated with activation in the parasympathetic autonomic nervous system through the vagus nerve. Across 4 studies, participants witnessed others suffer while we recorded physiological measures, including heart rate, respiration, skin conductance, and a measure of vagal activity called respiratory sinus arrhythmia (RSA). Participants exhibited greater RSA during the compassion induction compared with a neutral control (Study 1), another positive emotion (Study 2), and a prosocial emotion lacking appraisals of another person’s suffering (Study 3). Greater RSA during the experience of compassion compared with the neutral or control emotion was often accompanied by lower heart rate and respiration but no difference in skin conductance. In Study 4, increases in RSA during compassion positively predicted an established composite of compassion-related words, continuous self-reports of compassion, and nonverbal displays of compassion. Compassion, a core affective component of empathy and prosociality, is associated with heightened parasympathetic activity.
If you simply google "vagus nerve" you will find sites listing means of enhancing vagus activity and tone by self stimulation to improve mood and functioning, as an antidote to anxiety, etc.

Tuesday, April 14, 2015

The science of mind wandering.

I want to pass on this reference to an Ann. Rev. of Psychology article by Smallwood and Schooler, an extensive review and description of mind wandering, its disengagement from external input, its costs and benefits, its association with medial brain structures of the default mode network, its regulation by more lateral frontal executive control and external attention networks, etc. Here is the abstract, followed by a useful summary graphic:
Conscious experience is fluid; it rarely remains on one topic for an extended period without deviation. Its dynamic nature is illustrated by the experience of mind wandering, in which attention switches from a current task to unrelated thoughts and feelings. Studies exploring the phenomenology of mind wandering highlight the importance of its content and relation to meta-cognition in determining its functional outcomes. Examination of the information-processing demands of the mind-wandering state suggests that it involves perceptual decoupling to escape the constraints of the moment, its content arises from episodic and affective processes, and its regulation relies on executive control. Mind wandering also involves a complex balance of costs and benefits: Its association with various kinds of error underlines its cost, whereas its relationship to creativity and future planning suggest its potential value. Although essential to the stream of consciousness, various strategies may minimize the downsides of mind wandering while maintaining its productive aspects.

Evidence for the default mode network (DMN) as the substrate of the self-generated thought. The DMN is a large-scale brain network defined by the temporal correlation between activity in two core regions on the medial surface of the cortex, known as the posterior cingulate and medial prefrontal cortex. These regions form the core of the DMN (yellow) and interact with subnetworks including the medial temporal lobe subsystem (green) and the dorsal medial subsystem (blue). Meta-analyses using Neurosynth have shown that the core of this system tends to be engaged in self-referential processes, the medial temporal subsystem is engaged by episodic processes, and the dorsal medial subsystem is engaged by social processes. Together, these forms of thought are similar to the content of the self-generated thoughts that often occur during mind wandering, providing important evidence for the involvement of these regions in the mental content that occurs during mind wandering. Studies using experience sampling in conjunction with functional magnetic resonance imaging have shown that these regions show heightened activity during periods of task-unrelated thought (a–c). These brain images show that regions of the core aspects of the DMN exhibited greater activity during periods of task-unrelated thought. Regions: A, dorsal anterior cingulate cortex; B, ventral-medial medial pre-frontal cortex; C, posterior cingulate cortex; D, right temporal-parietal junction; E, dorsal medial prefrontal cortex; F, left rostral-lateral prefrontal cortex.

Monday, April 13, 2015

Manipulating moral decisions by exploiting eye gaze.

Here is a fascinating piece of work from Pärnamets et al.:
Eye gaze is a window onto cognitive processing in tasks such as spatial memory, linguistic processing, and decision making. We present evidence that information derived from eye gaze can be used to change the course of individuals’ decisions, even when they are reasoning about high-level, moral issues. Previous studies have shown that when an experimenter actively controls what an individual sees the experimenter can affect simple decisions with alternatives of almost equal valence. Here we show that if an experimenter passively knows when individuals move their eyes the experimenter can change complex moral decisions. This causal effect is achieved by simply adjusting the timing of the decisions. We monitored participants’ eye movements during a two-alternative forced-choice task with moral questions. One option was randomly predetermined as a target. At the moment participants had fixated the target option for a set amount of time we terminated their deliberation and prompted them to choose between the two alternatives. Although participants were unaware of this gaze-contingent manipulation, their choices were systematically biased toward the target option. We conclude that even abstract moral cognition is partly constituted by interactions with the immediate environment and is likely supported by gaze-dependent decision processes. By tracking the interplay between individuals, their sensorimotor systems, and the environment, we can influence the outcome of a decision without directly manipulating the content of the information available to them.
We hypothesized that participants’ eye gaze reveals their decision process owing to general coupling between sensorimotor decision processes. By using a gaze-contingent probe and selecting when a decision is prompted the resulting choice can be biased toward a randomly predetermined option.

Friday, April 10, 2015

The Apple Watch will be making us more sociable and human??

I enjoy techie stuff (with the recent exception of taking too many hours to figure out wireless network problems that caused my Zeppelin AirPlay speaker to stop working), and like many others, have been wondering why on earth I would want to buy the forthcoming Apple Watch. Manjoo's recent NYTimes review makes an interesting point regarding whether the Watch would push us to new heights of collective narcissism:
...I became intrigued by the opposite possibility — that it could address some of the social angst wrought by smartphones. The Apple Watch’s most ingenious feature is its “taptic engine,” which alerts you to different digital notifications by silently tapping out one of several distinct patterns on your wrist. As you learn the taps over time, you will begin to register some of them almost subconsciously: incoming phone calls and alarms feel throbbing and insistent, a text feels like a gentle massage from a friendly bumblebee, and a coming calendar appointment is like the persistent pluck of a harp. After a few days, I began to get snippets of information from the digital world without having to look at the screen — or, if I had to look, I glanced for a few seconds rather than minutes.
If such on-body messaging systems become more pervasive, wearable devices can become more than a mere flashy accessory to the phone. The Apple Watch could usher in a transformation of social norms just as profound as those we saw with its brother, the smartphone — except, amazingly, in reverse.
Manjoo also notes in a companion article:
There is something magical about having a computer that no one notices right there on your wrist. I first experienced this magic while at lunch with a colleague. I’m usually a wreck at such meetings, because while I try to refrain from looking at my phone, my mind is constantly jonesing for the next digital hit.
Lunch today is different. My iPhone remains hidden deep in my pocket, and to all the world I am the picture of the predigital man. It is the middle of the workday, the busiest time for digital communication. Yet with the Apple Watch on my wrist, my mind remains calm, my compulsion to check the phone suddenly at bay. After spending the last few days customizing my notification settings, my watch is a hornet’s nest of activity. It buzzes every few minutes to indicate incoming email and texts, tweets or Slack messages.
The buzzes aren’t annoying. They go completely unnoticed by my colleague, while to an addict like me they’re little hits of methadone — just enough contact with the digital world to whet my appetite, but not nearly as immersive, and socially disruptive, as reaching for my phone and eyeing its screen. I not only register the watch’s buzzes, but several times while we’re chatting, I surreptitiously check its screen. I scan some incoming messages and tweets, and even flag a couple of emails for later.
At the end of the meal, I ask my colleague if she’s noticed me checking my watch. She is surprised; she hasn’t seen it.
Fowler's review in the Wall Street Journal suggests that, given the paucity of Apps at startup and the inevitable bug fixes that will be forthcoming, it might be judicious to let the dust settle and buy the Apple Watch 2 when it appears a bit further down the road. Or, if you are a techie addict, you might pay $400 for the 42mm Sport Version when it becomes available.

Thursday, April 09, 2015

A drug for compassion?

Sáez et al. enhance human egalitarian behavior in humans with tolcapone - a drug approved for use with Parkinson's disease patients - which prolongs the effect of brain dopamine by inhibiting the enzyme that breaks it down.


Highlights and abstract from their paper:
•Dopamine is causally associated with human prosocial behavior
•Pharmacological dopamine enhancement led to prioritizing of egalitarian motives
•Computational modeling of inequity aversion captures drug-induced changes
•Results support involvement of dopamine in computing prosocial valuation signal 
Summary 
Egalitarian motives form a powerful force in promoting prosocial behavior and enabling large-scale cooperation in the human species. At the neural level, there is substantial, albeit correlational, evidence suggesting a link between dopamine and such behavior. However, important questions remain about the specific role of dopamine in setting or modulating behavioral sensitivity to prosocial concerns. Here, using a combination of pharmacological tools and economic games, we provide critical evidence for a causal involvement of dopamine in human egalitarian tendencies. Specifically, using the brain penetrant catechol-O-methyl transferase (COMT) inhibitor tolcapone, we investigated the causal relationship between dopaminergic mechanisms and two prosocial concerns at the core of a number of widely used economic games: (1) the extent to which individuals directly value the material payoffs of others, i.e., generosity, and (2) the extent to which they are averse to differences between their own payoffs and those of others, i.e., inequity. We found that dopaminergic augmentation via COMT inhibition increased egalitarian tendencies in participants who played an extended version of the dictator game. Strikingly, computational modeling of choice behavior revealed that tolcapone exerted selective effects on inequity aversion, and not on other computational components such as the extent to which individuals directly value the material payoffs of others. Together, these data shed light on the causal relationship between neurochemical systems and human prosocial behavior and have potential implications for our understanding of the complex array of social impairments accompanying neuropsychiatric disorders involving dopaminergic dysregulation.

Wednesday, April 08, 2015

A natural compound for chilling out?

As I sit here typing this morning, I'm munching on cocoa nibs, inspired by Friedman's review pointing to the work of Dincheva et al. on a gene whose enzyme product (fatty acid amide hydrolase, FAAH) deactivates and thus regulates the action of our endogenous cannabinoid anandamide (which cocoa nibs contain in small amounts).



Individuals with a common human mutation in the FAAH gene have higher brain levels of anandamide and lower levels of background anxiety, due to enhanced connectivity between the frontal lobes and the amygdala. Here is the Dincheva abstract describing actions of the FAAH gene in a mouse model:
Cross-species studies enable rapid translational discovery and produce the broadest impact when both mechanism and phenotype are consistent across organisms. We developed a knock-in mouse that biologically recapitulates a common human mutation in the gene for ​fatty acid amide hydrolase (​FAAH) (C385A; rs324420), the primary catabolic enzyme for the endocannabinoid ​anandamide. This common polymorphism impacts the expression and activity of ​FAAH, thereby increasing ​anandamide levels. Here, we show that the genetic knock-in mouse and human variant allele carriers exhibit parallel alterations in biochemisty, neurocircuitry and behaviour. Specifically, there is reduced ​FAAH expression associated with the variant allele that selectively enhances fronto-amygdala connectivity and fear extinction learning, and decreases anxiety-like behaviours. These results suggest a gain of function in fear regulation and may indicate for whom and for what anxiety symptoms ​FAAH inhibitors or exposure-based therapies will be most efficacious, bridging an important translational gap between the mouse and human.

Tuesday, April 07, 2015

Physical activity's 'modest' effects on cognitive vitality

Prakash et al., in the Annual Review of Psychology, have reviewed the epidemiological literature on physical activity and exercise and their relationship to cognition and age-associated neurodegenerative diseases such as Alzheimer's disease. While the abstract uses the word "modest" to describe the effect of physical activity on preserving or enhancing cognitive vitality, the numerous studies and meta-analyses they cite demonstrate a reduction in all-cause mortality of 20-30% associated with physical activity, and a 38% reduction in risk of cognitive decline in nondemented participants with high physical activity levels, and a 35% reduction in participants with low to moderate levels. Thus there is no evidence for an increase in relative risk reduction in cognitive decline as a function of increasing levels of physical activity. Here is their abstract:
We examine evidence supporting the associations among physical activity (PA), cognitive vitality, neural functioning, and the moderation of these associations by genetic factors. Prospective epidemiological studies provide evidence for PA to be associated with a modest reduction in relative risk of cognitive decline. An evaluation of the PA-cognition link across the life span provides modest support for the effect of PA on preserving and even enhancing cognitive vitality and the associated neural circuitry in older adults, with the majority of benefits seen for tasks that are supported by the prefrontal cortex and the hippocampus. The literature on children and young adults, however, is in need of well-powered randomized controlled trials. Future directions include a more sophisticated understanding of the dose-response relationship, the integration of genetic and epigenetic approaches, inclusion of multimodal imaging of brain-behavior changes, and finally the design of multimodal interventions that may yield broader improvements in cognitive function.

Monday, April 06, 2015

The transparent avatar in your brain.

While doing a review of some recent writing by Thomas Metzinger, I came across this brief and lucid video, which I pass on...

 

Friday, April 03, 2015

Awareness breaks down brain’s network modularity.

Godwin et al. provide an analysis showing that awareness emerges from global changes in the brain’s functional connectivity:
Neurobiological theories of awareness propose divergent accounts of the spatial extent of brain changes that support conscious perception. Whereas focal theories posit mostly local regional changes, global theories propose that awareness emerges from the propagation of neural signals across a broad extent of sensory and association cortex. Here we tested the scalar extent of brain changes associated with awareness using graph theoretical analysis applied to functional connectivity data acquired at ultra-high field while subjects performed a simple masked target detection task. We found that awareness of a visual target is associated with a degradation of the modularity of the brain’s functional networks brought about by an increase in intermodular functional connectivity. These results provide compelling evidence that awareness is associated with truly global changes in the brain’s functional connectivity.

Thursday, April 02, 2015

Origins of Narcissism in Children

An interesting study from Brummelman et al. showing that narcissism in children is predicted by parental overvaluation, not by lack of parental warmth, apparently because children internalize parents' inflated views of them:
Narcissism levels have been increasing among Western youth, and contribute to societal problems such as aggression and violence. The origins of narcissism, however, are not well understood. Here, we report, to our knowledge, the first prospective longitudinal evidence on the origins of narcissism in children. We compared two perspectives: social learning theory (positing that narcissism is cultivated by parental overvaluation) and psychoanalytic theory (positing that narcissism is cultivated by lack of parental warmth). We timed the study in late childhood (ages 7–12), when individual differences in narcissism first emerge. In four 6-mo waves, 565 children and their parents reported child narcissism, child self-esteem, parental overvaluation, and parental warmth. Four-wave cross-lagged panel models were conducted. Results support social learning theory and contradict psychoanalytic theory: Narcissism was predicted by parental overvaluation, not by lack of parental warmth. Thus, children seem to acquire narcissism, in part, by internalizing parents’ inflated views of them (e.g., “I am superior to others” and “I am entitled to privileges”). Attesting to the specificity of this finding, self-esteem was predicted by parental warmth, not by parental overvaluation. These findings uncover early socialization experiences that cultivate narcissism, and may inform interventions to curtail narcissistic development at an early age.

Wednesday, April 01, 2015

Cognitive abilities across the lifespan.

Hartshorne and Germine do a massive analysis of changes in cognitive abilities across the life span, showing that digit symbol coding, digit span, vocabulary, working memory, and facial emotion perception peak and decline at different times, with the last of these continuing to improve into later ages.

For each task, the median (interior line), interquartile range (left and right edges of boxes), and 95% confidence interval (whiskers) are shown. WM = working memory.
Their abstract:
Understanding how and when cognitive change occurs over the life span is a prerequisite for understanding normal and abnormal development and aging. Most studies of cognitive change are constrained, however, in their ability to detect subtle, but theoretically informative life-span changes, as they rely on either comparing broad age groups or sparse sampling across the age range. Here, we present convergent evidence from 48,537 online participants and a comprehensive analysis of normative data from standardized IQ and memory tests. Our results reveal considerable heterogeneity in when cognitive abilities peak: Some abilities peak and begin to decline around high school graduation; some abilities plateau in early adulthood, beginning to decline in subjects’ 30s; and still others do not peak until subjects reach their 40s or later. These findings motivate a nuanced theory of maturation and age-related decline, in which multiple, dissociable factors differentially affect different domains of cognition.

Tuesday, March 31, 2015

The Singularity—an Urban Legend?

Clips from an interesting essay by Daniel Dennett:
The Singularity—the fateful moment when AI surpasses its creators in intelligence and takes over the world—is a meme worth pondering. It has the earmarks of an urban legend: a certain scientific plausibility ("Well, in principle I guess it's possible!") coupled with a deliciously shudder-inducing punch line ("We'd be ruled by robots!")
...these alarm calls distract us from a more pressing problem...we are on the verge of abdicating control to artificial agents that can't think, prematurely putting civilization on auto-pilot. The process is insidious because each step of it makes good local sense, is an offer you can't refuse. You'd be a fool today to do large arithmetical calculations with pencil and paper when a hand calculator is much faster and almost perfectly reliable...and why memorize train timetables when they are instantly available on your smart phone? Leave the map-reading and navigation to your GPS system; it isn't conscious; it can't think in any meaningful sense, but it's much better than you are at keeping track of where you are and where you want to go.
What's wrong with turning over the drudgery of thought to such high-tech marvels? Nothing, so long as (1) we don't delude ourselves, and (2) we somehow manage to keep our own cognitive skills from atrophying.
(1) It is very, very hard to imagine (and keep in mind) the limitations of entities that can be such valued assistants, and the human tendency is always to over-endow them with understanding—as we have known since Joe Weizenbaum's notorious Eliza program of the early 1970s. This is a huge risk, since we will always be tempted to ask more of them than they were designed to accomplish, and to trust the results when we shouldn't.
(2) Use it or lose it. As we become ever more dependent on these cognitive prostheses, we risk becoming helpless if they ever shut down. The Internet is not an intelligent agent (well, in some ways it is) but we have nevertheless become so dependent on it that were it to crash, panic would set in and we could destroy society in a few days. That's an event we should bend our efforts to averting now, because it could happen any day.
The real danger, then, is not machines that are more intelligent than we are usurping our role as captains of our destinies. The real danger is basically clueless machines being ceded authority far beyond their competence.

Monday, March 30, 2015

Quiet

From my long queue of potential MindBlog post items, I pull up Judith Warner’s 2012 review of Susan Cain’s Book “Quiet”, which argues for the power of introverts, and pass on a few clips from the review:
The introverts who are the subject of Susan Cain’s new book, “Quiet,” … view their tendency toward solitary activity, quiet reflection and reserve as “a second-class personality trait, somewhere between a disappointment and a pathology,” … Too often denigrated and frequently overlooked in a society that’s held in thrall to an “Extrovert Ideal — the omnipresent belief that the ideal self is gregarious, alpha and comfortable in the spotlight,”
Many of the self-avowed introverts she meets in the course of this book, which combines on-the-scenes reporting with a wide range of social science research and a fair bit of “quiet power” cheerleading, ape extroversion. Though some fake it well enough to make it, going along to get along in a country that rewards the out­going, something precious, the author says, is lost in this masquerade. Unchecked extroversion — a personality trait Cain ties to ebullience, excitability, dominance, risk-taking, thick skin, boldness and a tendency toward quick thinking and thoughtless action — has actually, she argues, come to pose a real menace of late. The outsize reward-seeking tendencies of the hopelessly ­outer-directed helped bring us the bank meltdown of 2008 as well as disasters like Enron, she claims. With our economy now in ruins, Cain writes, it’s time to establish “a greater balance of power” between those who rush to speak and do and those who sit back and think. Introverts — who, according to Cain, can count among their many virtues the fact that “they’re relatively immune to the lures of wealth and fame” — must learn to “embrace the power of quiet.” And extroverts should learn to sit down and shut up.
Warner is critical os several aspects of Cain’s book, such as the assumption that most introverts are actually suffering in their self-esteem, also:
...her definition of introversion — a temperamental inner-­directedness first identified as a core personality trait by Carl Jung in 1921 — widens constantly; by the end of the book, it has expanded to include all who are “reflective, cerebral, bookish, unassuming, sensitive, thoughtful, serious, contemplative, subtle, introspective, inner-directed, gentle, calm, modest, solitude-seeking, shy, risk-averse, thin-skinned.” This widening of the definition makes introversion so broad a category, including, basically, all that is wise and good, that it’s largely meaningless, except as yet another vehicle for promoting self-esteem

Friday, March 27, 2015

Altering the oxytocin receptor gene enhances perception of anger and fear.

Puglia et al. find that the epigenetic modification of methylating the DNA of the oxytocin receptor gene (OXTR) decreases the control of amygdala fear responses by brain regions involved in affect appraisal and emotion regulation. Thus individuals with higher levels of OXTR methylation are more reactive to negative emotional facial cues. Clips from their introduction:
A peripheral hormone and central neuromodulator, oxytocin influences a variety of social and affective processes including affiliative behaviors, care-giving, and stress reactivity. Intranasally administered, oxytocin has also been implicated in specialized components of social cognition, such as trust, envy, and mentalizing...One way oxytocin may influence behavior is through anxiety reduction; intranasal oxytocin has been shown to have anxiolytic effects on brain systems supporting affective responses to negatively arousing stimuli. These findings support oxytocin’s role in anxiety reduction and make it an attractive candidate in neurobiological models of psychiatric disorders...Methylation of 5′-Cytosine-phosphate-Guanine-3′ (CpG) dinucleotide pairs in DNA is a highly investigated epigenetic modification that may influence behavioral phenotypes. DNA methylation within the promoter region of OXTR is variable within the population, and methylation of specific OXTR CpG sites reduces transcription of the gene. High levels of OXTR methylation at these same sites have been associated with autism, callous unemotional traits, and anorexia nervosa, suggesting the utility of OXTR methylation as a biomarker of phenotypic variability.
Their abstract:
In humans, the neuropeptide oxytocin plays a critical role in social and emotional behavior. The actions of this molecule are dependent on a protein that acts as its receptor, which is encoded by the oxytocin receptor gene (OXTR). DNA methylation of OXTR, an epigenetic modification, directly influences gene transcription and is variable in humans. However, the impact of this variability on specific social behaviors is unknown. We hypothesized that variability in OXTR methylation impacts social perceptual processes often linked with oxytocin, such as perception of facial emotions. Using an imaging epigenetic approach, we established a relationship between OXTR methylation and neural activity in response to emotional face processing. Specifically, high levels of OXTR methylation were associated with greater amounts of activity in regions associated with face and emotion processing including amygdala, fusiform, and insula. Importantly, we found that these higher levels of OXTR methylation were also associated with decreased functional coupling of amygdala with regions involved in affect appraisal and emotion regulation. These data indicate that the human endogenous oxytocin system is involved in attenuation of the fear response, corroborating research implicating intranasal oxytocin in the same processes. Our findings highlight the importance of including epigenetic mechanisms in the description of the endogenous oxytocin system and further support a central role for oxytocin in social cognition. This approach linking epigenetic variability with neural endophenotypes may broadly explain individual differences in phenotype including susceptibility or resilience to disease.
Individuals with increased methylation of OXTR display elevated amygdala response to angry and fearful faces. Mean Z statistic values are plotted against percent OXTR methylation for each participant (n = 98). Gray shading indicates 95% confidence interval around the best-fit line. (Inset) Z statistic map of voxels shows significant main effect of OXTR methylation depicted in MNI space (y = 0), FDR corrected at q less than 0.05. Region of interest is depicted in blue.

Thursday, March 26, 2015

Information overload is filter failure.

I pass on the following brief lucid piece by Jay Rosen.You might also have a look at Peder Zane's "In the Age of Information, Specializing to Survive."
Information Overload
We should retire the idea that goes by the name "information overload." It is no longer useful.
The Internet scholar Clay Shirky puts it well: "There's no such thing as information overload. There's only filter failure." If your filters are bad there is always too much to attend to, and never enough time. These aren't trends powered by technology. They are conditions of life.
Filters in a digital world work not by removing what is filtered out; they simply don't select for it. The unselected material is still there, ready to be let through by someone else's filter. Intelligent filters, which is what we need, come in three kinds:
A smart person who takes in a lot and tells you what you need to know. The ancient term for this is "editor." The front page of the New York Times still works this way.
An algorithm that sifts through the choices other smart people have made, ranks them, and presents you with the top results. That's how Google works— more or less.
A machine learning system that over time gets to know your interests and priorities and filters the world for you in a smarter and smarter way. Amazon uses systems like that. Here's the best definition of information that I know of: information is a measure of uncertainty reduced. It's deceptively simple. In order to have information, you need two things: an uncertainty that matters to us (we're having a picnic tomorrow, will it rain?) and something that resolves it (weather report.) But some reports create the uncertainty that is later to be solved.
Suppose we learn from news reports that the National Security Agency "broke" encryption on the Internet. That's information! It reduces uncertainty about how far the U.S. government was willing to go. (All the way.) But the same report increases uncertainty about whether there will continue to be a single Internet, setting us up for more information when that larger picture becomes clearer. So information is a measure of uncertainty reduced, but also of uncertainty created. Which is probably what we mean when we say: "well, that raises more questions than it answers."
Filter failure occurs not from too much information but from too much incoming "stuff" that neither reduces existing uncertainty nor raises questions that count for us. The likely answer is to combine the three types of filtering: smart people who do it for us, smart crowds and their choices, smart systems that learn by interacting with us as individuals. It's at this point that someone usually shouts out: what about serendipity? It's a fair point. We need filters that listen to our demands, but also let through what we have no way to demand because we don't know about it yet. Filters fail when they know us too well and when they don't know us well enough.

Wednesday, March 25, 2015

Expert listening to music alters gene transcription...So?

I can't resist comment on a piece generated by PsyBlog, "Classical Music's Surprising Effect on Genes Vital to Memory and Learning." ..."How 20 minutes of Mozart affects the expression of genes vital to learning, memory and more…" that points to work of Järvelä​ and collaborators, whose abstract states:
To verify whether listening to classical music has any effect on human transcriptome, we performed genome-wide transcriptional profiling from the peripheral blood of participants after listening to classical music (n = 48), and after a control study without music exposure (n = 15). As musical experience is known to influence the responses to music, we compared the transcriptional responses of musically experienced and inexperienced participants separately with those of the controls. Comparisons were made based on two subphenotypes of musical experience: musical aptitude and music education. In musically experienced participants, we observed the differential expression of 45 genes (27 up- and 18 down-regulated) and 97 genes (75 up- and 22 down-regulated) respectively based on subphenotype comparisons...
Apart from issues of control and sample sizes, there is the problem that almost distinctive behavior (athletic engagement, meditation, whatever, can be shown to alter genes transcription. Presenting a trained (versus a naive) person with stimuli in the trained area of expertise would be expected to alter the “transcriptome” to support the brain processing required for that expertise, regardless of what the area is (music, visual art, literature, athletics). We're a long way from being able to make much sense of or interpret the statements that conclude the abstract:
...the up-regulated genes are primarily known to be involved in the secretion and transport of dopamine, neuron projection, protein sumoylation, long-term potentiation and dephosphorylation. Down-regulated genes are known to be involved in ATP synthase-coupled proton transport, cytolysis, and positive regulation of caspase, peptidase and endopeptidase activities. One of the most up-regulated genes, alpha-synuclein (SNCA), is located in the best linkage region of musical aptitude on chromosome 4q22.1 and is regulated by GATA2, which is known to be associated with musical aptitude. Several genes reported to regulate song perception and production in songbirds displayed altered activities, suggesting a possible evolutionary conservation of sound perception between species. We observed no significant findings in musically inexperienced participants.
To be sure, primitive first steps such as these are useful, but it is unfortunate when their popularization by blogs vying for attention proceeds to overinterpretation and hyperbole.

Tuesday, March 24, 2015

Thought for the day: America devolving into a plutocracy...

A clip from Tom Engelhardt writing in Salon:
...let me be as clear as I can be about something that seems murky indeed: this period doesn’t represent a version, no matter how perverse or extreme, of politics as usual; nor is the 2016 campaign an election as usual; nor are we experiencing Washington as usual. Put together our 1% elections, the privatization of our government, the de-legitimization of Congress and the presidency, as well as the empowerment of the national security state and the U.S. military, and add in the demobilization of the American public (in the name of protecting us from terrorism), and you have something like a new ballgame.
While significant planning has been involved in all of this, there may be no ruling pattern or design. Much of it may be happening in a purely seat-of-the-pants fashion. In response, there has been no urge to officially declare that something new is afoot, let alone convene a new constitutional convention. Still, don’t for a second think that the American political system isn’t being rewritten on the run by interested parties in Congress, our present crop of billionaires, corporate interests, lobbyists, the Pentagon, and the officials of the national security state.
Out of the chaos of this prolonged moment and inside the shell of the old system, a new culture, a new kind of politics, a new kind of governance is being born right before our eyes. Call it what you want. But call it something. Stop pretending it’s not happening.

Transcranial direct current stimulation increases propensity to mind-wander

Alelrod et al. show that stimulation of the frontal lobe areas involved in our attentional network increase mind wandering associated with our default mode network (see previous posts here and here for discussion of these networks).
Humans mind-wander quite intensely. Mind wandering is markedly different from other cognitive behaviors because it is spontaneous, self-generated, and inwardly directed (inner thoughts). However, can such an internal and intimate mental function also be modulated externally by means of brain stimulation? Addressing this question could also help identify the neural correlates of mind wandering in a causal manner, in contrast to the correlational methods used previously (primarily functional MRI). In our study, participants performed a monotonous task while we periodically sampled their thoughts to assess mind wandering. Concurrently, we applied transcranial direct current stimulation (tDCS). We found that stimulation of the frontal lobes [anode electrode at the left dorsolateral prefrontal cortex (DLPFC), cathode electrode at the right supraorbital area], but not of the occipital cortex or sham stimulation, increased the propensity to mind-wander. These results demonstrate for the first time, to our knowledge, that mind wandering can be enhanced externally using brain stimulation, and that the frontal lobes play a causal role in mind-wandering behavior. These results also suggest that the executive control network associated with the DLPFC might be an integral part of mind-wandering neural machinery.

Monday, March 23, 2015

Impulse control with weak currents applied to the head - a new therapy?

Spieser et al. apply a very small current (1 milliamp) using the electrodes shown in the figure to slightly hyperpolarize, or make less excitable, the supplementary motor cortex, and find that this inhibits impulsive responses in a reaction time task.
To err is human. However, an inappropriate urge does not always result in error. Impulsive errors thus entail both a motor system capture by an urge to act and a failed inhibition of that impulse. Here we show that neuromodulatory electrical stimulation of the supplementary motor complex in healthy humans leaves action urges unchanged but prevents them from turning into overt errors. Subjects performed a choice reaction-time task known to trigger impulsive responses, leading to fast errors that can be revealed by analyzing accuracy as a function of poststimulus time. Yet, such fast errors are only the tip of the iceberg: electromyography (EMG) revealed fast subthreshold muscle activation in the incorrect response hand in an even larger proportion of overtly correct trials, revealing covert response impulses not discernible in overt behavior. Analyzing both overt and covert response tendencies enables to gauge the ability to prevent these incorrect impulses from turning into overt action errors. Hyperpolarizing the supplementary motor complex using transcranial direct current stimulation (tDCS) preserves action impulses but prevents their behavioral expression. This new combination of detailed behavioral, EMG, and tDCS techniques clarifies the neurophysiology of impulse control, and may point to avenues for improving impulse control deficits in various neurologic and psychiatric disorders.

Friday, March 20, 2015

Losing the music - Aging affects the perception of musical harmony

An open access article from Bones and Plack:
When two musical notes with simple frequency ratios are played simultaneously, the resulting musical chord is pleasing and evokes a sense of resolution or “consonance”. Complex frequency ratios, on the other hand, evoke feelings of tension or “dissonance”. Consonance and dissonance form the basis of harmony, a central component of Western music. In earlier work, we provided evidence that consonance perception is based on neural temporal coding in the brainstem (Bones et al., 2014). Here, we show that for listeners with clinically normal hearing, aging is associated with a decline in both the perceptual distinction and the distinctiveness of the neural representations of different categories of two-note chords. Compared with younger listeners, older listeners rated consonant chords as less pleasant and dissonant chords as more pleasant. Older listeners also had less distinct neural representations of consonant and dissonant chords as measured using a Neural Consonance Index derived from the electrophysiological “frequency-following response.” The results withstood a control for the effect of age on general affect, suggesting that different mechanisms are responsible for the perceived pleasantness of musical chords and affective voices and that, for listeners with clinically normal hearing, age-related differences in consonance perception are likely to be related to differences in neural temporal coding.
By the way, the same issue of J. Neuroscience has another interesting article by Vaden et al. on noting cingulo-opercular cortical activity that predicts how well older adults recognize speech in noise.

Thursday, March 19, 2015

Thomas Metzinger on (the absence of) our conscious agency.

The edge.org question for 2014 was “What scientific idea is ready for retirement?” I want to pass on a few clips from Metzinger’s lucid brief contribution, and strongly suggest that you read it.
Thinking is not something you do. Most of the time it is something that happens to you. Cutting-edge research on the phenomenon of Mind Wandering now clearly shows how almost all of us, for more than two thirds of their conscious lifetime, are not in control of their conscious thought processes…The sudden loss of inner autonomy—which all of us experience many hundred times every day—seems to be based on a cyclically recurring process in the brain. The ebb and flow of autonomy and meta-awareness might well be a kind of attentional see-sawing between our inner and outer worlds, caused by a constant competition between the brain networks underlying spontaneous subpersonal thinking and goal-oriented cognition.
Interestingly, the neural correlate of non-autonomous conscious thought overlaps to a considerable degree with ongoing activity in what neuroscientists call the "default mode network". I think that one global function of Mind Wandering may be "autobiographical self-model maintenance". Mind Wandering creates an adaptive form of self-deception, namely, an illusion of personal identity across time. It helps to maintain a fictional "self" that then lays the foundation for important achievements like reward prediction or delay discounting. As a philosopher, my conceptual point is that only if an organism simulates itself as being one and the same across time will it be able to represent reward events or the achievement of goals as a fulfillment of its own goals, as happening to the same entity. I like to call this the "Principle of Virtual Identity Formation": Many higher forms of intelligence and adaptive behavior, including risk management, moral cognition and cooperative social behavior, functionally presuppose a self-model that portrays the organism as a single entity that endures over time. Because we are really only cognitive systems, complex processes without any precise identity criteria, the formation of an (illusory) identity across time can only be achieved on a virtual level, for example through the creation of an automatic narrative. This could be the more fundamental and overarching computational goal of mind wandering, and one it may share with dreaming. If I am right, the default mode of the autobiographical self-modeling constructs a domain-general functional platform enabling long-term motivation and future planning.
Mental autonomy (and how it can be improved) will be one of the hottest topics for the future. There is even a deep link between mental and political autonomy—you cannot sustain one without the other. Because there are not only bodily actions, but also mental actions, autonomy has to do with freedom—and in one of the deepest and most fundamental senses of the word. But the ability to act autonomously implies not only reasons, arguments and rationality. Much more fundamentally it refers to the capacity to wilfully inhibit, suspend, or terminate our own actions—bodily, socially, or mentally. The breakdown of this ability is what we call Mind Wandering.

Wednesday, March 18, 2015

Hunger promotes acquisition of nonfood objects

Here is a fascinating nugget of information from Xu et al.:
Hunger motivates people to consume food, for which finding and acquiring food is a prerequisite. We test whether the acquisition component spills over to nonfood objects: Are hungry people more likely to acquire objects that cannot satisfy their hunger? Five laboratory and field studies show that hunger increases the accessibility of acquisition-related concepts and the intention to acquire not only food but also nonfood objects. Moreover, people act on this intention and acquire more nonfood objects (e.g., binder clips) when they are hungry, both when these items are freely available and when they must be paid for. However, hunger does not influence how much they like nonfood objects. We conclude that a basic biologically based motivation can affect substantively unrelated behaviors that cannot satisfy the motivation. This presumably occurs because hunger renders acquisition-related concepts and behaviors more accessible, which influences decisions in situations to which they can be applied.

Tuesday, March 17, 2015

What can music ensembles tell us about social cognition and interaction?

D'Ausilio et al. note that most studies of how cognition and brain organization is shaped by social factors have used subjects in defined experimental settings, rather than natural ones. The problem is that experimental rigor is inversely related to ecological naturalness. They suggest that musical ensemble performance offers a promising solution for balancing the trade-off between experimental control and ecological naturalness. Here is their list of features that make music a promising avenue for social cognition research.
Ecological validity: ensemble musicians participate in a socially-relevant interaction, obviating the need to introduce an artificial task, manipulation, or training to induce a social context.
Motivational factors: motivation is an inherent part of music and hence it is not necessary to employ extrinsic techniques (monetary compensation, competition, or response-contingent reward) to trigger the emergence of interaction.
Generalizability: musicality is a widespread human capacity, enabling almost everyone to sing together with others and to produce rhythms through body movements (e.g., simple drumming or dance).
Multi-level interactivity: information transfer is both continuous (body movements) and discrete (musical sounds). Furthermore, musicians’ movements that function to produce sound on an instrument can be dissociated from those that are not necessary for sound production (e.g., ancillary movements that serve expressive functions) [15]. These properties allow the investigation of the multi-level communicative functions (hierarchical musical structure and expressive intentions) of musical social interaction.
Temporal dependencies: information transfer is not only based on the content of an individual's instantaneous response but also is affected by rhythmic timing, tempo, and the degree of interpersonal synchrony.
Formal description of interaction: the musical score is a script-like description of the interaction that the experimenter can manipulate to control the emergence of social structures and different roles (e.g., leader vs follower) played by each musician.
The authors briefly review research that that traverses a continuum of ecological interaction. These classes include an individual interacting with a recording, a computer-controlled virtual partner that responds to the individual, another individual in a duo, multiple individuals in mixed ensembles (extending to large orchestras), and others in the presence of a live audience.

Monday, March 16, 2015

The happiness gap between conservatives and liberals debunked

Given the number of MindBlog posts that have passed on research supporting the standard orthodoxy that conservatives are happier than liberals, I immediately pass on this abstract from Wojcik et al. reporting experiments that prove just the opposite (See also the NYTimes summary of this work.)
Research suggesting that political conservatives are happier than political liberals has relied exclusively on self-report measures of subjective well-being. We show that this finding is fully mediated by conservatives’ self-enhancing style of self-report (study 1; N = 1433) and then describe three studies drawing from “big data” sources to assess liberal-conservative differences in happiness-related behavior (studies 2 to 4; N = 4936). Relative to conservatives, liberals more frequently used positive emotional language in their speech and smiled more intensely and genuinely in photographs. Our results were consistent across large samples of online survey takers, U.S. politicians, Twitter users, and LinkedIn users. Our findings illustrate the nuanced relationship between political ideology, self-enhancement, and happiness and illuminate the contradictory ways that happiness differences can manifest across behavior and self-reports.

Friday, March 13, 2015

Emotional foundations of cognitive control.

Cognitive control (self control, self regulation) allows us to restrain from temptations of the present to focus on more long term goals. Emotion is usually cast as its enemy. Inzlicht et al. suggest, however, that cognitive control rises from and is dependent on emotional primitives, in particular the negative affect associated with conflicting stimuli.  Their highlights and abstract:
• Cognitive control can be understood as an emotional process. 
• Negative affect is an integral, instantiating aspect of cognitive control. 
• Cognitive conflict has an emotional cost, evoking a host of emotional primitives. 
• Emotion is not an inert byproduct of conflict, but helps in recruiting control.
Often seen as the paragon of higher cognition, here we suggest that cognitive control is dependent on emotion. Rather than asking whether control is influenced by emotion, we ask whether control itself can be understood as an emotional process. Reviewing converging evidence from cybernetics, animal research, cognitive neuroscience, and social and personality psychology, we suggest that cognitive control is initiated when goal conflicts evoke phasic changes to emotional primitives that both focus attention on the presence of goal conflicts and energize conflict resolution to support goal-directed behavior. Critically, we propose that emotion is not an inert byproduct of conflict but is instrumental in recruiting control. Appreciating the emotional foundations of control leads to testable predictions that can spur future research.

Thursday, March 12, 2015

Observing brain correlates of self affirmation and its healthy consequences

From the introduction of Falk et. al. :
...according to the World Health Organization, “60% to 85% of people in the world—from both developed and developing countries—lead sedentary lifestyles”...self-relevant health messages can be perceived to be threatening to self-worth and are often met with resistance...Affirmation of core values (self-affirmation) preceding potentially threatening messages can reduce resistance and increase intervention effectiveness Therefore, one way to increase receptivity to messages discouraging sedentary behavior among sedentary individuals may be to affirm their core values in unrelated domains before exposure to the messages.
We focused on the brain’s ventromedial prefrontal cortex (VMPFC) during exposure to potentially threatening health messages emphasizing the need to be more active and less sedentary in a group of sedentary adults. VMPFC is the most common region implicated in self-related processing and is also a key region, along with the ventral striatum, implicated in positive valuation of stimuli.
Their abstract:
Health communications can be an effective way to increase positive health behaviors and decrease negative health behaviors; however, those at highest risk are often most defensive and least open to such messages. For example, increasing physical activity among sedentary individuals affects a wide range of important mental and physical health outcomes, but has proven a challenging task. Affirming core values (i.e., self-affirmation) before message exposure is a psychological technique that can increase the effectiveness of a wide range of interventions in health and other domains; however, the neural mechanisms of affirmation’s effects have not been studied. We used functional magnetic resonance imaging (fMRI) to examine neural processes associated with affirmation effects during exposure to potentially threatening health messages. We focused on an a priori defined region of interest (ROI) in ventromedial prefrontal cortex (VMPFC), a brain region selected for its association with self-related processing and positive valuation. Consistent with our hypotheses, those in the self-affirmation condition produced more activity in VMPFC during exposure to health messages and went on to increase their objectively measured activity levels more. These findings suggest that affirmation of core values may exert its effects by allowing at-risk individuals to see the self-relevance and value in otherwise-threatening messages.

(A) VMPFC ROI. (B) Participants who showed higher levels of VMPFC activity during exposure to health messages subsequently decreased their sedentary behavior more in the month following the scan, controlling for baseline sedentary behavior and demographics.

Wednesday, March 11, 2015

Spontaneous emergence of shared social conventions.

Centola and Baronchelli have recruited subjects from the world wide web to play a live game. They demonstate that myopic players interacting in sequential pairs in social networks can unintentionally create percolating cascades of coordinated behavior. Their findings demonstrate that social conventions can spontaneously evolve in large human populations without any institutional mechanisms to facilitate the process. The results highlight the causal role played by network connectivity in the dynamics of establishing shared norms. I pass on first the abstract and then sections on experimental design and methods.
How do shared conventions emerge in complex decentralized social systems? This question engages fields as diverse as linguistics, sociology, and cognitive science. Previous empirical attempts to solve this puzzle all presuppose that formal or informal institutions, such as incentives for global agreement, coordinated leadership, or aggregated information about the population, are needed to facilitate a solution. Evolutionary theories of social conventions, by contrast, hypothesize that such institutions are not necessary in order for social conventions to form. However, empirical tests of this hypothesis have been hindered by the difficulties of evaluating the real-time creation of new collective behaviors in large decentralized populations. Here, we present experimental results—replicated at several scales—that demonstrate the spontaneous creation of universally adopted social conventions and show how simple changes in a population’s network structure can direct the dynamics of norm formation, driving human populations with no ambition for large scale coordination to rapidly evolve shared social conventions.
Experimental Design
Each live game, or experimental “trial,” consisted of a set of participants, a specific social network structure, and a prespecified number of rounds to play. When participants arrived to play the game, they were randomly assigned to positions within a social network. In a given round of the game, two network “neighbors” were chosen at random to play with one another. Both players simultaneously assigned names to a pictured object (i.e., a human face), blindly attempting to coordinate in the real-time exchange of naming choices. If the players coordinated on a name, they were rewarded with a successful payment; if they failed, they were penalized (Materials and Methods). After a single round, the participants could see only the choices that they and their partner had made, and their cumulative pay was updated accordingly. They were then randomly assigned to play with a new neighbor in their social network, and a new round would begin. The object that participants were trying to name was the same for the entire duration of the game, and for all members of the game. Participants in the study did not have any information about the size of the population that was attempting to coordinate nor about the number of neighbors to whom they were connected.
Materials and Methods
Participants in the study were recruited at large from the World Wide Web. When participants arrived to play a game, they were randomly assigned to an experimental condition (i.e., a social network) and then randomly assigned to a position within that social network. In a given round of the game, two network neighbors were chosen at random to play with one another. Both players simultaneously assigned names to a pictured object (e.g., a human face), blindly attempting to coordinate in the real-time exchange of naming choices. If the players coordinated on a name, they were rewarded with a successful payment ($0.50); if they failed, they were penalized (–$0.25). (Participants could not go into debt, so failures did not incur a penalty if a participant had a balance of $0.) After a single round, the participants could see only the choices that they and their partner had made, and their cumulative pay was updated accordingly. They were then randomly assigned to play with a new neighbor in their social network, and a new round would begin. The object that participants were trying to name was the same for the entire duration of the game and for all members of the game. An experimental trial concluded when all members completed the specified number of rounds. Participants did not have any information about the size of the population nor about the number of neighbors to whom they were connected nor even about which individuals they were interacting with in a given round. We explored the dynamics of convention formation over different network sizes between 24 and 96 and degrees of social connectedness. However, the controls within the experimental design ensured that the informational resources provided to subjects were identical across all conditions of the study.

Tuesday, March 10, 2015

Predictions and the brain: how musical sounds become rewarding

I want to point to the review article in Trends in Cognitive Science by Salimpoor, Zatorre, and collaborators  that outlines brain mechanisms underlying the pleasure we can feel on listening to music. (Motivated readers can request a copy of the article from me.)
•Dopamine release in mesolimbic reward circuits leads to reinforcement tied to predictions and outcomes. 
•Musical pleasure involves complex interactions between dopamine systems and cortical areas. 
•Individual variability in superior temporal cortex may explain varied musical preferences. 
•Cognitive, auditory, affective, and reward circuits interact to make music pleasurable. Music has always played a central role in human culture. 
The question of how musical sounds can have such profound emotional and rewarding effects has been a topic of interest throughout generations. At a fundamental level, listening to music involves tracking a series of sound events over time. Because humans are experts in pattern recognition, temporal predictions are constantly generated, creating a sense of anticipation. We summarize how complex cognitive abilities and cortical processes integrate with fundamental subcortical reward and motivation systems in the brain to give rise to musical pleasure. This work builds on previous theoretical models that emphasize the role of prediction in music appreciation by integrating these ideas with recent neuroscientific evidence.
(added note.... I just realized that I am repeating mention of the same article I pointed to in my more thorough Feb. 13 post! I guess the 72 year old brain is getting a bit forgetful.)

Monday, March 09, 2015

Hugging can make you less likely to catch a virus cold.

Daily social stress is known to correlate with susceptibility to cold virus infection. Cohen et al. ask whether social support and the actual receipt of physical touch during daily life—being hugged—attenuate the association of interpersonal stressors (social conflict) with subsequent risk for infection, cold signs, and clinical disease in response to an experimentally administered cold virus. They find, not surprisingly, that the answer is yes, consistent with numerous studies that have shown that social support boosts immune function. Here is their abstract:
Perceived social support has been hypothesized to protect against the pathogenic effects of stress. How such protection might be conferred, however, is not well understood. Using a sample of 404 healthy adults, we examined the roles of perceived social support and received hugs in buffering against interpersonal stress-induced susceptibility to infectious disease. Perceived support was assessed by questionnaire, and daily interpersonal conflict and receipt of hugs were assessed by telephone interviews on 14 consecutive evenings. Subsequently, participants were exposed to a virus that causes a common cold and were monitored in quarantine to assess infection and illness signs. Perceived support protected against the rise in infection risk associated with increasing frequency of conflict. A similar stress-buffering effect emerged for hugging, which explained 32% of the attenuating effect of support. Among infected participants, greater perceived support and more-frequent hugs each predicted less-severe illness signs. These data suggest that hugging may effectively convey social support.

Friday, March 06, 2015

Human language reveals a universal positivity bias

Dodds et al. have constructed 24 corpora (collections of writing) spread across 10 languages: English, Spanish, French, German, Brazilian Portuguese, Korean, Chinese (Simplified), Russian, Indonesian, and Arabic, including books, news outlets, social media, the, television and movie subtitles, and music lyrics. They note the most commonly used words, and how those words are perceived by individuals (on a happiness scale of 1-9) to provide a clear confirmation of the Pollyanna hypothesis suggested in 1969 by Boucher and Osgood - that there is a universal positivity bias in human communication. The authors illustrate the use of their "hedonometer", a language-based instrument for measuring expressed happiness, by constructing “happiness time series” for three famous works of literature, evaluated in their original languages of English, Russian, and French, respectively: Melville’s Moby Dick, Dostoyevsky’s Crime and Punishment, and Dumas’ The Count of Monte Cristo. Their abstract:
Using human evaluation of 100,000 words spread across 24 corpora in 10 languages diverse in origin and culture, we present evidence of a deep imprint of human sociality in language, observing that (i) the words of natural human language possess a universal positivity bias, (ii) the estimated emotional content of words is consistent between languages under translation, and (iii) this positivity bias is strongly independent of frequency of word use. Alongside these general regularities, we describe interlanguage variations in the emotional spectrum of languages that allow us to rank corpora. We also show how our word evaluations can be used to construct physical-like instruments for both real-time and offline measurement of the emotional content of large-scale texts.

Thursday, March 05, 2015

Chickens count from the left, just like us!

Rugani et. al. show (Brugger's summary) that
...3-day old chicks associate small numerosities with the left side, and large ones with the right side, of a given space. The results show that newborn chicks can understand both relative and absolute quantities, and also suggest that the brain may be prewired in how it relates numbers to space. The work casts doubt on the importance of language and symbolic thought for the ability to represent discrete quantities larger than 3 and to develop a sense of numerical order and counting routines. Field studies of avian behavior have previously documented this ability in adult birds.
Abstract:
Humans represent numbers along a mental number line (MNL), where smaller values are located on the left and larger on the right. The origin of the MNL and its connections with cultural experience are unclear: Pre-verbal infants and nonhuman species master a variety of numerical abilities, supporting the existence of evolutionary ancient precursor systems. In our experiments, 3-day-old domestic chicks, once familiarized with a target number (5), spontaneously associated a smaller number (2) with the left space and a larger number (8) with the right space. The same number (8), though, was associated with the left space when the target number was 20. Similarly to humans, chicks associate smaller numbers with the left space and larger numbers with the right space.
More from Brugger's summary:
A more specific insight from Rugani et al.'s study is that a chick's sense of numerical order is tightly coupled with its sense of space: “More than” is equivalent to “to the right of.” This leads to a left-to-right directionality in the mapping of numbers to space—a finding that puts several previous proposals for the origin of mental number lines into perspective. One reason why researchers have assumed that this kind of numerical mapping is an invention of the human mind is its cultural modification. In cultures with a left-to-right reading and writing direction, the number line expands from left to right, but cultures with an opposite directional handling of script align numbers from right to left. Obviously, reading/writing direction cannot be the ultimate cause of directionality, nor can finger-counting habits. Presumably, the predominant role of the right hemisphere for numerical ordering biases initial attention to the left side of both physical and number space. Together with a preference for increasing over decreasing order—already apparent in 4-month-old human infants—the biological default of a number line would point from left to right.

Wednesday, March 04, 2015

The high from nicotine depends on whether you think it is there.

Fascinating observations from Gu et al.:
Significance
Nicotine is the primary addictive substance in tobacco, which stimulates neural pathways mediating reward processing. However, pure biochemical explanations are not sufficient to account for the difficulty in quitting and remaining smoke-free among smokers, and in fact cognitive factors are now considered to contribute critically to addiction. Using model-based functional neuroimaging, we show that smokers’ prior beliefs about nicotine specifically impact learning signals defined by principled computational models of mesolimbic dopamine systems. We further demonstrate that these specific changes in neural signaling are accompanied by measurable changes in smokers’ choice behavior. Our findings suggest that subjective beliefs can override the physical presence of a powerful drug like nicotine by modulating learning signals processed in the brain’s reward system.
Abstract
Little is known about how prior beliefs impact biophysically described processes in the presence of neuroactive drugs, which presents a profound challenge to the understanding of the mechanisms and treatments of addiction. We engineered smokers’ prior beliefs about the presence of nicotine in a cigarette smoked before a functional magnetic resonance imaging session where subjects carried out a sequential choice task. Using a model-based approach, we show that smokers’ beliefs about nicotine specifically modulated learning signals (value and reward prediction error) defined by a computational model of mesolimbic dopamine systems. Belief of “no nicotine in cigarette” (compared with “nicotine in cigarette”) strongly diminished neural responses in the striatum to value and reward prediction errors and reduced the impact of both on smokers’ choices. These effects of belief could not be explained by global changes in visual attention and were specific to value and reward prediction errors. Thus, by modulating the expression of computationally explicit signals important for valuation and choice, beliefs can override the physical presence of a potent neuroactive compound like nicotine. These selective effects of belief demonstrate that belief can modulate model-based parameters important for learning. The implications of these findings may be far ranging because belief-dependent effects on learning signals could impact a host of other behaviors in addiction as well as in other mental health problems.

Tuesday, March 03, 2015

Immune cells drive resilience to stress.

Evidence has been accumulating recently for back and forth interactions between the brain and immune system. Brachman et al. have now made the observation that lymphocytes isolated from stressed out mice, when transferred to naive mice, reduce anxiety and depression like behaviors in the naive mice. It would be interesting to see if a similar sort of transfer in humans had the same effect.
We examined whether cells of the adaptive immune system retain the memory of psychosocial stress and thereby alter mood states and CNS function in the host. Lymphocytes from mice undergoing chronic social defeat stress or from unstressed control mice were isolated and adoptively transferred into naive lymphopenic Rag2−/− mice. Changes in affective behavior, hippocampal cell proliferation, microglial activation states, and blood cytokine levels were examined in reconstituted stress-naive mice. The mice receiving lymphocytes from defeated donors showed less anxiety, more social behavior, and increased hippocampal cell proliferation compared with those receiving no cells or cells from unstressed donors. Mice receiving stressed immune cells had reduced pro-inflammatory cytokine levels in the blood relative to the other groups, an effect opposite to the elevated donor pro-inflammatory cytokine profile. Furthermore, mice receiving stressed immune cells had microglia skewed toward an anti-inflammatory, neuroprotective M2-like phenotype, an effect opposite the stressed donors' M1-like pro-inflammatory profile. However, stress had no effect on lymphocyte surface marker profiles in both donor and recipient mice. The data suggest that chronic stress-induced changes in the adaptive immune system, contrary to conferring anxiety and depressive behavior, protect against the deleterious effects of stress. Improvement in affective behavior is potentially mediated by reduced peripheral pro-inflammatory cytokine load, protective microglial activity, and increased hippocampal cell proliferation. The data identify the peripheral adaptive immune system as putatively involved in the mechanisms underlying stress resilience and a potential basis for developing novel rapid-acting antidepressant therapies.

Monday, March 02, 2015

MindStuff: A Guide for the Curious User

When I am trying to collect together some ideas to form a lecture or longer piece of work, I frequently think “Haven’t I seen that before?” …. and sure enough I find the ideas better put together in a previous essay I’ve done than in my current effort. I’ve just gone back and read through my 2005 web essay: MindStuff: A guide for the curious user. My reaction is the same as when last summer’s Chaos seminar group discussed the last chapter of my Biology of Mind Book. I think to myself, “Did I really write this? This is good stuff…” While there are a number of places I would tweak and update the text, the MindStuff essay still provides fundamental and useful information, particularly the “The Guide” section that starts halfway through the essay. The purpose of this post is just to point to the text.

Friday, February 27, 2015

The neurochemistry of music.

I want to point to an interesting review article by Chanda and Levitin, that summaries studies showing how music engages four of our bodies' fundamental neurochemical systems. I pass on the abstract and the start of the introduction to the article to give you an idea of its scope:
Music is used to regulate mood and arousal in everyday life and to promote physical and psychological health and well-being in clinical settings. However, scientific inquiry into the neurochemical effects of music is still in its infancy. In this review, we evaluate the evidence that music improves health and well-being through the engagement of neurochemical systems for (i) reward, motivation, and pleasure; (ii) stress and arousal; (iii) immunity; and (iv) social affiliation. We discuss the limitations of these studies and outline novel approaches for integration of conceptual and technological advances from the fields of music cognition and social neuroscience into studies of the neurochemistry of music. 
Introduction 
Music is one of a small set of human cultural universals, evoking a wide range of emotions, from exhilaration to relaxation, joy to sadness, fear to comfort, and even combinations of these. Many people use music to regulate mood and arousal, much as they use caffeine or alcohol. Neurosurgeons use it to enhance concentration, armies to coordinate movements and increase cooperation, workers to improve attention and vigilance, and athletes to increase stamina and motivation.
The notion that ‘music is medicine’ has roots that extend deep into human history through healing rituals practiced in pre-industrial, tribal-based societies. In contemporary society, music continues to be used to promote health and well-being in clinical settings, such as for pain management, relaxation, psychotherapy, and personal growth. Although much of this clinical use of music is based on ad hoc or unproven methods, an emerging body of literature addresses evidence-based music interventions through peer-reviewed scientific experiments. In this review, we examine the scientific evidence supporting claims that music influences health through neurochemical changes in the following four domains:
(i) reward, motivation and pleasure 
(ii) stress and arousal 
(iii) immunity 
(iv) social affiliation.
These domains parallel, respectively, the known neurochemical systems of
(i) dopamine and opioids 
(ii) cortisol, corticotrophin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) 
(iii) serotonin and the peptide derivatives of proopiomelanocortin (POMC), including alpha-melanocyte stimulating hormone and beta-endorphin 
(iv) oxytocin.
Although the evidence is often weak or indirect and all studies suffer from important limitations, the reviewed evidence does provide preliminary support for the claim that neurochemical changes mediate the influence of music on health.

Thursday, February 26, 2015

Twitter predicts mortality from heart disease!

Here is an interesting item from Eichstaedt, Seligman, and collaborators:
Hostility and chronic stress are known risk factors for heart disease, but they are costly to assess on a large scale. We used language expressed on Twitter to characterize community-level psychological correlates of age-adjusted mortality from atherosclerotic heart disease (AHD). Language patterns reflecting negative social relationships, disengagement, and negative emotions—especially anger—emerged as risk factors; positive emotions and psychological engagement emerged as protective factors. Most correlations remained significant after controlling for income and education. A cross-sectional regression model based only on Twitter language predicted AHD mortality significantly better than did a model that combined 10 common demographic, socioeconomic, and health risk factors, including smoking, diabetes, hypertension, and obesity. Capturing community psychological characteristics through social media is feasible, and these characteristics are strong markers of cardiovascular mortality at the community level.

Wednesday, February 25, 2015

Metacognitive mechanisms underlying lucid dreaming.

Metacognition is the ability to observe, reflect on, and report one's own mental states during wakefulness. Dreaming is not typically accessible to this kind of monitoring, except in people who are lucid dreamers, aware that they are dreaming while in the sleep state (I can do this). Filevich et al. have looked for relationships between the neural correlates of lucid dreaming and thought monitoring:
Lucid dreaming is a state of awareness that one is dreaming, without leaving the sleep state. Dream reports show that self-reflection and volitional control are more pronounced in lucid compared with nonlucid dreams. Mostly on these grounds, lucid dreaming has been associated with metacognition. However, the link to lucid dreaming at the neural level has not yet been explored. We sought for relationships between the neural correlates of lucid dreaming and thought monitoring.
Human participants completed a questionnaire assessing lucid dreaming ability, and underwent structural and functional MRI. We split participants based on their reported dream lucidity. Participants in the high-lucidity group showed greater gray matter volume in the frontopolar cortex (BA9/10) compared with those in the low-lucidity group. Further, differences in brain structure were mirrored by differences in brain function. The BA9/10 regions identified through structural analyses showed increases in blood oxygen level-dependent signal during thought monitoring in both groups, and more strongly in the high-lucidity group.
Our results reveal shared neural systems between lucid dreaming and metacognitive function, in particular in the domain of thought monitoring. This finding contributes to our understanding of the mechanisms enabling higher-order consciousness in dreams.

Tuesday, February 24, 2015

The neuroscience of motivated cognition.

I want to point to this interesting open source article by Hughes and Zaki, who review research from social psychology and cognitive neuroscience that provides insight into the structure of motivated cognition (that can bias or distort reality), suggesting that it pervades information processing and is often effortless. Here are the opening paragraphs:
People often believe that their thinking aims squarely at gaining an accurate impression of reality. Upon closer inspection, this assumption collapses. Instead, like the inhabitants of Garrison Keillor's Lake Woebegon, individuals often see themselves and close others as possessing unrealistically high levels of positive attributes such as likeability, morality, and attractiveness. This bias persists among individuals who should know better: over 90% college professors believe their work is better than that of their peers, CIA analysts overestimate the accuracy of their predictions for future events, and doctors overconfidently estimate their medical knowledge.
These cases exemplify the phenomenon of motivated cognition, by which the goals and needs of individuals steer their thinking towards desired conclusions. A variety of motivations pervasively shapes cognition. For example, people wish to live in a coherent and consistent world. This leads people to recognize patterns where there are none, perceive control over random events, and shift their attitudes to be consistent with their past behaviors. People also need to feel good about themselves and about others with whom they identify. As such, people often self-enhance, evaluating themselves as having more desirable personalities and rosier future prospects than their peers, and taking personal credit for successes, but not failures. People likewise elevate their relationship partners and in-group members (e.g., people who share their political affiliation) in demonstrably unrealistic ways. Motivations can also have the opposite effect, leading people to derogate out-group members, even when the lines that divide ‘us’ from ‘them’ are defined de novo by researchers.
The authors follow this by noting studies demonstrating motivated cognition in perception, attention, decision making, etc.

Monday, February 23, 2015

MindBlog's 9th anniversary

I realize that I have let MindBlog's 9th birthday slip past without note. The Feb. 6, 2006 post that started the blog, Dangerous Ideas, is no less relevant today than then. I don't pay attention to statistics, but the Blogger platform automatically reports that 200-500 actively engage a given post, with that number rising to to 500-1000 over the next several weeks. Feedburner reports ~ 1.6 million views of ~3,000 posts since MindBlog started. I don't have a sense of how many people make checking MindBlog posts a daily ritual. (A brief comment to this post on your use, as well as any critique, would be welcome!) As Andrew Sullivan (who is signing off from his well-known blog) notes, a daily routine seriously detracts from longer term projects with more depth. I'm finding myself spending more time trying to work up some unifying ideas about metacognition, and also taking more time with the activity I care most about, classical piano practice and performance (which dates back to ~1948, rather than 2006). I'm not going to worry if the daily posting frequency takes a hit.

What is different about the brains of "SuperAgers"

We all probably know some people well into their 80's and 90's who seem to maintain crystal clear intelligence, presence, and memory. A group of collaborators at Northwestern University has studied a group of such individuals, and was able to do postmortem anatomy of the brains of five them. Compared with average elderly individuals, they found fewer Alzheimer-type neurofibrillary tangles and an increased packing density of von Economo neurons, especially in the anterior cingulate. Von Economo neurons, large spindle shaped cells distinctive to humans and great apes, are located in only two parts of the brain: the anterior cingulate cortex, deep in the center of the brain, and the frontoinsular cortex, located inside the frontal lobes. In humans, both of these structures appear to be involved in aspects of social cognition such as trust, empathy, and feelings of guilt and embarrassment.
This human study is based on an established cohort of “SuperAgers,” 80+-year-old individuals with episodic memory function at a level equal to, or better than, individuals 20–30 years younger. A preliminary investigation using structural brain imaging revealed a region of anterior cingulate cortex that was thicker in SuperAgers compared with healthy 50- to 65-year-olds. Here, we investigated the in vivo structural features of cingulate cortex in a larger sample of SuperAgers and conducted a histologic analysis of this region in postmortem specimens. A region-of-interest MRI structural analysis found cingulate cortex to be thinner in cognitively average 80+ year olds (n = 21) than in the healthy middle-aged group (n = 18). A region of the anterior cingulate cortex in the right hemisphere displayed greater thickness in SuperAgers (n = 31) compared with cognitively average 80+ year olds and also to the much younger healthy 50–60 year olds (p < 0.01). Postmortem investigations were conducted in the cingulate cortex in five SuperAgers, five cognitively average elderly individuals, and five individuals with amnestic mild cognitive impairment. Compared with other subject groups, SuperAgers showed a lower frequency of Alzheimer-type neurofibrillary tangles (p < 0.05). There were no differences in total neuronal size or count between subject groups. Interestingly, relative to total neuronal packing density, there was a higher density of von Economo neurons (p < 0.05), particularly in anterior cingulate regions of SuperAgers. These findings suggest that reduced vulnerability to the age-related emergence of Alzheimer pathology and higher von Economo neuron density in anterior cingulate cortex may represent biological correlates of high memory capacity in advanced old age.

Friday, February 20, 2015

Training the mind not to wander with brain feedback.

deBettencourt and collaborators at Princeton University have placed student subjects in an MRI machine while they were performing a sustained attention task. When the machine detected indicators of an attentional lapse, it provided feedback when attention waned by making the task more difficult. Students used this to learn that their attention was lagging and performance improved. The abstract:
Lapses of attention can have negative consequences, including accidents and lost productivity. Here we used closed-loop neurofeedback to improve sustained attention abilities and reduce the frequency of lapses. During a sustained attention task, the focus of attention was monitored in real time with multivariate pattern analysis of whole-brain neuroimaging data. When indicators of an attentional lapse were detected in the brain, we gave human participants feedback by making the task more difficult. Behavioral performance improved after one training session, relative to control participants who received feedback from other participants' brains. This improvement was largest when feedback carried information from a frontoparietal attention network. A neural consequence of training was that the basal ganglia and ventral temporal cortex came to represent attentional states more distinctively. These findings suggest that attentional failures do not reflect an upper limit on cognitive potential and that attention can be trained with appropriate feedback about neural signals.