Eldest children are less cooperative, trusting, and reciprocating

In a brief review titled "Why your older brother didn't share" ScienceNow points to interesting work by Courtiol et al. Their abstract:

Explaining the behavioural variations observed between individuals is an important step for understanding the evolution of human cooperation and personality traits. Birth order is a potentially important variable that implies physical and cognitive differences between siblings and differential access to parental resources during childhood. These differences have been shown to influence several personality characteristics in adulthood. We tested the hypothesis that birth order can shape adult cooperative behaviours towards nonkin. An anonymous investment game was played by 510 unrelated students. The results of the game show that firstborns were less trustful and reciprocated less than others. No significant differences in trust or reciprocity were found among laterborn and only children based on birth order. Firstborn status was a better predictor of cooperativeness than age, sex, income or religion. These results constitute some of the first experimental evidence that birth order differences established within the family can persist in adult behaviour among nonkin. We discuss the implications of this finding for the evolution of human cooperation.

Spoken language and symbolic gestures processed by same brain areas

Xu et al perform MRI measurements that suggest that anterior and posterior perisylvian areas identified since the mid-19th century as the core of the brain's language system (including Broca's and Wernicke's area) may in fact function as a modality-independent semiotic system that plays a broader role in human communication, linking meaning with symbols whether these are words, gestures, images, sounds, or objects.

Symbolic gestures, such as pantomimes that signify actions (e.g., threading a needle) or emblems that facilitate social transactions (e.g., finger to lips indicating “be quiet”), play an important role in human communication. They are autonomous, can fully take the place of words, and function as complete utterances in their own right. The relationship between these gestures and spoken language remains unclear. We used functional MRI to investigate whether these two forms of communication are processed by the same system in the human brain. Responses to symbolic gestures, to their spoken glosses (expressing the gestures' meaning in English), and to visually and acoustically matched control stimuli were compared in a randomized block design....esults support a model in which bilateral modality-specific areas in superior and inferior temporal cortices extract salient features from vocal-auditory and gestural-visual stimuli respectively. However, both classes of stimuli activate a common, left-lateralized network of inferior frontal and posterior temporal regions in which symbolic gestures and spoken words may be mapped onto common, corresponding conceptual representations. We suggest that these anterior and posterior perisylvian areas, identified since the mid-19th century as the core of the brain's language system, are not in fact committed to language processing, but may function as a modality-independent semiotic system that plays a broader role in human communication, linking meaning with symbols whether these are words, gestures, images, sounds, or objects.

Figure - Common areas of activation for processing symbolic gestures and spoken language minus their respective baselines, identified using a random effects conjunction analysis. The resultant t map is rendered on a single subject T1 image: 3D surface rendering above, axial slices with associated z axis coordinates, below.

When seeing outweighs feeling.

Anders et al. make an interesting observation on patients who are blind in part of their visual field due to damage of a portion of the visual cortex. They still register negative feelings and somatic changes when a threatening stimulus is presented to their blind area, presumably due to sub-cortical pathways. However, when the visual stimulus is visible and receives full cortical processing, the patients’ phenomenal experience of affect does not closely reflect somatic changes. This decoupling of phenomenal affective experience and somatic changes is associated with an increase of activity in the left ventrolateral prefrontal cortex and a decrease of affect-related somatosensory activity. Here is their abstract:

Affective neuroscience has been strongly influenced by the view that a ‘feeling’ is the perception of somatic changes and has consequently often neglected the neural mechanisms that underlie the integration of somatic and other information in affective experience. Here, we investigate affective processing by means of functional magnetic resonance imaging in nine cortically blind patients. In these patients, unilateral postgeniculate lesions prevent primary cortical visual processing in part of the visual field which, as a result, becomes subjectively blind. Residual subcortical processing of visual information, however, is assumed to occur in the entire visual field. As we have reported earlier, these patients show significant startle reflex potentiation when a threat-related visual stimulus is shown in their blind visual field. Critically, this was associated with an increase of brain activity in somatosensory-related areas, and an increase in experienced negative affect. Here, we investigated the patients’ response when the visual stimulus was shown in the sighted visual field, that is, when it was visible and cortically processed. Despite the fact that startle reflex potentiation was similar in the blind and sighted visual field, patients reported significantly less negative affect during stimulation of the sighted visual field. In other words, when the visual stimulus was visible and received full cortical processing, the patients’ phenomenal experience of affect did not closely reflect somatic changes. This decoupling of phenomenal affective experience and somatic changes was associated with an increase of activity in the left ventrolateral prefrontal cortex and a decrease of affect-related somatosensory activity. Moreover, patients who showed stronger left ventrolateral prefrontal cortex activity tended to show a stronger decrease of affect-related somatosensory activity. Our findings show that similar affective somatic changes can be associated with different phenomenal experiences of affect, depending on the depth of cortical processing. They are in line with a model in which the left ventrolateral prefrontal cortex is a relay station that integrates information about subcortically triggered somatic responses and information resulting from in-depth cortical stimulus processing. Tentatively, we suggest that the observed decoupling of somatic responses and experienced affect, and the reduction of negative phenomenal experience, can be explained by a left ventrolateral prefrontal cortex-mediated inhibition of affect-related somatosensory activity.

A biological rationale for musical scales

An interesting article from Gill and Purves on musical scales, and how humans use only a few of the enormous number of possible tone combinations to create music. I found the illustrations to be fascinating and very educational:

Scales are collections of tones that divide octaves into specific intervals used to create music. Since humans can distinguish about 240 different pitches over an octave in the mid-range of hearing, in principle a very large number of tone combinations could have been used for this purpose. Nonetheless, compositions in Western classical, folk and popular music as well as in many other musical traditions are based on a relatively small number of scales that typically comprise only five to seven tones. Why humans employ only a few of the enormous number of possible tone combinations to create music is not known. Here we show that the component intervals of the most widely used scales throughout history and across cultures are those with the greatest overall spectral similarity to a harmonic series. These findings suggest that humans prefer tone combinations that reflect the spectral characteristics of conspecific vocalizations. The analysis also highlights the spectral similarity among the scales used by different cultures.

Rapid amygdala activation by fearful objects in our peripheral vision

Bayle et al. use Magnetoencephalography (MEG) to show that fearful objects presented to our peripheral field of vision while we are consciously looking at a central object cause rapid (80 msec) activation of the amygdala. If the fearful stimulus is presented to our central field of view and processed by the classical occipito-temporal visual pathway, it takes between 140 and 190 ms to register. Some clips:

In ecological situations, threatening stimuli often come out from the peripheral vision. Such aggressive messages must trigger rapid attention to the periphery to allow a fast and adapted motor reaction... Fearful and neutral faces were briefly presented in the central or peripheral visual field, and were followed by target faces stimuli. An event-related beamformer source analysis model was applied in three time windows following the first face presentations: 80 to 130 ms, 140 to 190 ms, and 210 to 260 ms. The frontal lobe and the right internal temporal lobe part, including the amygdala, reacted as soon as 80 ms of latency to fear occurring in the peripheral vision. For central presentation, fearful faces evoked the classical neuronal activity along the occipito-temporal visual pathway between 140 and 190 ms...Thus, the high spatio-temporal resolution of MEG allowed disclosing a fast response of a network involving medial temporal and frontal structures in the processing of fear related stimuli occurring unconsciously in the peripheral visual field.

A related study is offered by Sabatinelli et al., who examine the timing of emotional discrimination in the amygdala and ventral visual cortex.

Sequence of presentation influences our choice between alternatives.

FromMantonakis et al.:

When several choice options are sampled one at a time in a sequence and a single choice of the best option is made at the end of the sequence, which location in the sequence is chosen most often? We report a large-scale experiment that assessed tasting preferences in choice sets of two, three, four, or five wines. We found a large primacy effect—the first wine had a large advantage in the end-of-sequence choice. We also found that participants who were knowledgeable about wines showed a recency effect in the longer sequences.

The model they propose to explain their findings is interesting:

We propose that two biases operated within that sequential competitive evaluation process. First, a first-is-best bias accounts for the consistent primacy effect. Second, a bias in favor of each new wine among high-knowledge participants accounts for the recency effect, and for an interesting reason: Compared with the low-knowledge participants, the high-knowledge participants were more persistent in looking for a better wine later in the sequence—a plausible result of greater expertise. Thus, high-knowledge participants were likelier to make a comparison between their current favorite and the new wine when each new wine was sampled. Thus, there was a substantial chance that each new wine would beat the current favorite, and this habit produced the pronounced recency effect in longer sequences, especially for high-knowledge participants. For example, suppose that each new wine has a .30 chance of beating the current favorite, and the current favorite remains the preferred choice with a .70 probability. Note that these values are consistent with the size of the observed primacy effects (e.g., the first wine was chosen with approximately .70 probability in the two-option sets) and with the recency effects for the high-knowledge participants (the last wine was chosen with approximately .30 probability in the four-option and five-option sets).

We account for the lack of recency effects among the low-knowledge participants by proposing that they followed the pair-wise competitive-evaluation strategy less vigorously than the high-knowledge participants, eliminating the potential recency advantage. We speculate that the low-knowledge participants were more likely to be overwhelmed by the cognitive demands of the pair-wise competitive strategy as memory load and interference increased across the sampling trials.

The pair-wise model provides an almost perfect fit to the data if we add one more assumption about the comparison process. Thus far, we have assumed that all current favorites have a .70-versus-.30 advantage in all pair-wise comparisons. But if we suppose that the current-favorite advantage increases for later favorites (e.g., if the third option wins its pair-wise competition, its advantage increases to .75 vs. .25; if the fourth wins, its advantage is .80 vs. .20), then the model fits the data almost perfectly. This pair-wise-competition process model is impressive; its one failing is that it predicts a small recency effect for the three-option set for high-knowledge participants.

Experiencing our causality warps our sense of time.

Buehner et al. make the interesting observation that two events we know to be causally related are experienced as closer in time than similar unrelated events.  Thus, expectation warps our sense of time. :

According to widely held views in cognitive science harking back to David Hume, causality cannot be perceived directly, but instead is inferred from patterns of sensory experience, and the quality of these inferences is determined by perceivable quantities such as contingency and contiguity. We report results that suggest a reversal of Hume's conjecture: People's sense of time is warped by the experience of causality. In a stimulus-anticipation task, participants' response behavior reflected a shortened experience of time in the case of target stimuli participants themselves had generated, relative to equidistant, equally predictable stimuli they had not caused. These findings suggest that causality in the mind leads to temporal binding of cause and effect, and extend and generalize beyond earlier claims of intentional binding between action and outcome.

The year in ideas

The New York Times Magazine has just done its annual issue on what it selects, from A to Z, to be the most clever, important, silly or just plain weird innovations from all corners of the thinking world. Here are links to a few items that hooked me:

Drunken Ultimatums

Glow-in-the-dark dog

Good enough is the new great.

Google algorithm as an extinction model.

Guilty robots

Infant sleep is destiny

Literary Alzheimers 

The genius of crowds - massively collaborative mathematics

Random promotions 

This year's patents - a great humorous graphic

Modulation of our pain by emotions - cerebral and spinal sites

Our response to painful stimulation can be modulated by the emotional impact of viewing a pleasant or an unpleasant picture.  In an open access article, Roy et. al.  view the multiple sites associated with this effect - noting the central role of the right insula - by doing brain imaging of participants who received painful electric shocks while they viewed blocks of pleasant, unpleasant, or neutral pictures.:

Emotions have powerful effects on pain perception. However, the brain mechanisms underlying these effects remain largely unknown. In this study, we combined functional cerebral imaging with psychophysiological methods to explore the neural mechanisms involved in the emotional modulation of spinal nociceptive responses (RIII-reflex) and pain perception in healthy participants. Emotions induced by pleasant or unpleasant pictures modulated the responses to painful electrical stimulations in the right insula, paracentral lobule, parahippocampal gyrus, thalamus, and amygdala. Right insula activation covaried with the modulation of pain perception, consistent with a key role of this structure in the integration of pain signals with the ongoing emotion. In contrast, activity in the thalamus, amygdala, and several prefrontal areas was associated with the modulation of spinal reflex responses. Last, connectivity analyses suggested an involvement of prefrontal, parahippocampal, and brainstem structures in the cerebral and cerebrospinal modulation of pain by emotions. This multiplicity of mechanisms underlying the emotional modulation of pain is reflective of the strong interrelations between pain and emotions, and emphasizes the powerful effects that emotions can have on pain.

Why exercise makes you less anxious.

An article by Gretchen Reynolds summarizes work showing that exercise stimulates the synthesis of new brain cells that appear to be specifically buffered from exposure to stressful experience. Exercise also appears to cause beneficial changes in dopamine and serotonin regulation and the vulnerability to oxidative stress.

Stop me if I've told you this before......

Benedict Carey does a nice summary of work from Gopie and McCloud. Here is the Psychological Science Abstract of the work:

Everyone has recounted a story or joke to someone only to experience a nagging feeling that they may already have told this person this information. Remembering to whom one has told what, an ability that we term destination memory, has been overlooked by researchers despite its important social ramifications. Using a novel paradigm, we demonstrate that destination memory is more fallible than source memory—remembering the person from whom one has received information. In two experiments we increased and decreased self-focus, obtaining support for a theoretical framework that explains relatively poor destination memory performance as being the result of focusing attention on oneself and on the processes required to transmit information. Along with source memory, destination memory is an important component of episodic memory that plays a critical role in social interactions.

Why mindblog spends in the winter in Ft. Lauderdale...

View from the living room window of my Middleton, WI. home, just outside Madison, WI.  Seventeen inches of snow in Madison yesterday, today wind chill of -10 to -20 degrees fahrenheit. Getting to my Univ. of Wisconsin office would not be all that pleasant. Fort Lauderdale is sunny today with an unseasonable high of 87 degrees.

Political partisanship and perception of skin color tone

Interesting...from Caruso et al.:

People tend to view members of their own political group more positively than members of a competing political group. In this article, we demonstrate that political partisanship influences people's visual representations of a biracial political candidate's skin tone. In three studies, participants rated the representativeness of photographs of a hypothetical (Study 1) or real (Barack Obama; Studies 2 and 3) biracial political candidate. Unbeknownst to participants, some of the photographs had been altered to make the candidate's skin tone either lighter or darker than it was in the original photograph. Participants whose partisanship matched that of the candidate they were evaluating consistently rated the lightened photographs as more representative of the candidate than the darkened photographs, whereas participants whose partisanship did not match that of the candidate showed the opposite pattern. For evaluations of Barack Obama, the extent to which people rated lightened photographs as representative of him was positively correlated with their stated voting intentions and reported voting behavior in the 2008 Presidential election. This effect persisted when controlling for political ideology and racial attitudes. These results suggest that people's visual representations of others are related to their own preexisting beliefs and to the decisions they make in a consequential context.

Social isolation and inflammatory gene expression

My thanks to mindblog reader Ian for pointing out this article demonstrating how social isolation correlates with the expression of a large array of genes that elevate the risk of inflammatory disease. They did a DNA microarray analysis that identified 209 genes that were differentially expressed in circulating leukocytes from 14 high- versus low-lonely individuals, noting impaired transcription of glucocorticoid response genes and increased activity of pro-inflammatory transcription control pathways.

Men do everything they do to get laid?

Ted Maxwell of Intelligence Squared asks that I pass on this notice of a live online debate on evolutionary psychology at 18:45 GMT on Dec. 10.

Can it really be true that men do everything they do to get laid? Yes, argue the proponents of evolutionary psychology - because in their view the largely unconscious motive of human behaviour is to maximize reproductive success, which in men's case means getting sexual access to as many fertile women as possible. And so men - without necessarily being aware of it - do everything they do in order to get laid, and they are evolutionarily designed to behave in this way, because if they (and their ancestors) weren't, they wouldn't be here today. Women, on the other hand, have to be rather more careful about who they sleep with.

This, according to the theory, is why most millionaires, criminals and creative geniuses are men, why Intelligence Squared has such trouble finding good women speakers for its debates, and why middle-aged men tend to leave their wives for younger women. But what about the 50% of men who stick with their first marriage? And are we really saying that every creative endeavour - from the Sistine Chapel to the splitting of the atom - is nothing more than the manifestation of an underlying psychological impulse to copulate as much as possible?

My symbiosis with Google.

Yesterday's article by Brad Stone on Google in the NYTimes made me pause, yet again, to reflect on how utterly my professional and personal life have been altered by the 'free' services of this behemoth and 'the cloud,' most notably google search, Blogger, YouTube, gmail, Calendar and Contact synch of my iPhone and all my computers, etc. I have not filed away the hard copy of a scientific article in years, instead putting the PDF of any article of interest in the images file that supports this blog. I've just switched to their Chrome web browser which has blazing saddles speed compared with Firefox, Safari, Explorer, etc. (By the way, Kakutani has a review in the same NYTimes issue of "GOOGLED - The End of the World as We Know It" by Ken Auletta. titled "Still Counting the Ways to Infiltrate Daily Lives.")

The Brad Stone article describes partnerships with Twitter, Facebook and MySpace to bring updates from those services into its search index within seconds, so for example, you can see comments on the Copenhagen climate conference scrolling past as they are made. A new feature called Google Goggles, allows people to send Google a cellphone photograph of, say, a landmark or a book, and have information about the contents of the image returned to them instantly.

From Kakutani's review:

Because Google “enjoys a well-deserved reputation for earning the trust of users,” Mr. Auletta says, it is “hard to imagine an issue that could imperil the trust Google has achieved as quickly as could privacy.” He adds: “One Google executive whispers, ‘Privacy is an atomic bomb. Our success is based on trust.’ ”...If users, Mr. Auletta writes, “lost trust in Google, believed their private data was being exploited and shared with advertisers (or governments), the company regularly judged one of the world’s most trusted brands would commit suicide.”

“Google appears to be well positioned for the foreseeable future,” Mr. Auletta concludes, “but it is worth remembering that few companies maintain their dominance. At one point, few thought the Big Three auto companies would ever falter — or the three television networks or AT&T, IBM or AOL. For companies with histories of serious missteps — Apple, IBM — it was difficult to imagine that they’d rebound, until they did.”...In short, one of the few things it is impossible to Google is the future of Google.

The "Name-Ease" effect...

Interesting material from Labroo et al.:

We demonstrate that merely naming a research finding elicits feelings of ease (a "name-ease" effect). These feelings of ease can reduce or enhance the finding's perceived importance depending on whether people are making inferences about how understandable or how memorable the finding is. When people assess their understanding of a finding, feelings of ease reduce the finding's perceived importance. This is because people usually invest effort to understand important information but also mistakenly infer the reverse—namely, that information that requires effort to be understood is important. In contrast, when people assess the memorability of a finding, feelings of ease increase the finding's perceived importance. Because people usually recall important information easily, in this case they equate ease with importance. Psychological effects, economic principles, math theorems, jury cases, and decisions to fund medical research can all show these effects.

Primitive syntax in a monkey language?

Nicholas Wade points to some interesting work on the Campbell’s monkey in Tai Forest, Ivory Coast. (Later note: here is the link to the subsequent PNAS article.)

Our cooperative behavior is innate.

Nicholas Wade notes Tomasello's new book "Why We Cooperate." Helping behavior is observed in children and seems to be innate because it appears very early and before many parents start teaching children the rules of polite behavior. (The pictures shows a young child responding when an adult has dropped something.) Helping behavior can also be seen in infant chimpanzees under the right experimental conditions. Some clips:

Shared intentionality, in Dr. Tomasello’s view, is close to the essence of what distinguishes people from chimpanzees. A group of human children will use all kinds of words and gestures to form goals and coordinate activities, but young chimps seem to have little interest in what may be their companions’ minds...The shared intentionality lies at the basis of human society, Dr. Tomasello argues. From it flow ideas of norms, of punishing those who violate the norms and of shame and guilt for punishing oneself. Shared intentionality evolved very early in the human lineage, he believes, and its probable purpose was for cooperation in gathering food. Anthropologists report that when men cooperate in hunting, they can take down large game, which single hunters generally cannot do. Chimpanzees gather to hunt colobus monkeys, but Dr. Tomasello argues this is far less of a cooperative endeavor because the participants act on an ad hoc basis and do not really share their catch.

An interesting bodily reflection of humans’ shared intentionality is the sclera, or whites, of the eyes. All 200 or so species of primates have dark eyes and a barely visible sclera. All, that is, except humans, whose sclera is three times as large, a feature that makes it much easier to follow the direction of someone else’s gaze. Chimps will follow a person’s gaze, but by looking at his head, even if his eyes are closed. Babies follow a person’s eyes, even if the experimenter keeps his head still...Advertising what one is looking at could be a risk. Dr. Tomasello argues that the behavior evolved “in cooperative social groups in which monitoring one another’s focus was to everyone’s benefit in completing joint tasks.”..This could have happened at some point early in human evolution, when in order to survive, people were forced to cooperate in hunting game or gathering fruit. The path to obligatory cooperation — one that other primates did not take — led to social rules and their enforcement, to human altruism and to language.

Pre-natal androgens and risk taking...

Coates and Page follow up on a study I mentioned in an earlier post, this time examining risk taking as well as long-term profitability of traders in the City of London exchange:

Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D), which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.

How fear versus disgust regulate our attention.

Vermeulen et al. do a nice experiment demonstrating emotional effects on our attention, using the attentional blink to show that our noticing a rapidly presented second irrelevant input after seeing a fearful face is inhibited more than after we have seen a disgusting face.

It is well known that facial expressions represent important social cues. In humans expressing facial emotion, fear may be configured to maximize sensory exposure (e.g., increases visual input) whereas disgust can reduce sensory exposure (e.g., decreases visual input). To investigate whether such effects also extend to the attentional system, we used the “attentional blink” (AB) paradigm. Many studies have documented that the second target (T2) of a pair is typically missed when presented within a time window of about 200–500 ms from the first to-be-detected target (T1; i.e., the AB effect). It has recently been proposed that the AB effect depends on the efficiency of a gating system which facilitates the entrance of relevant input into working memory, while inhibiting irrelevant input. Following the inhibitory response on post T1 distractors, prolonged inhibition of the subsequent T2 is observed. We hypothesized that processing facial expressions of emotion would influence this attentional gating. Fearful faces would increase but disgust faces would decrease inhibition of the second target...We found that processing fear faces impaired the detection of T2 to a greater extent than did the processing disgust faces. This finding implies emotion-specific modulation of attention.

A dopamine receptor gene and emotional control

Blasi et al. note that variation of the Dopamine D₂ receptor gene is associated with emotional control as well as brain activity and connectivity during human emotion processing:

Personality traits related to emotion processing are, at least in part, heritable and genetically determined. Dopamine D₂ receptor signaling is involved in modulation of emotional behavior and activity of associated brain regions such as the amygdala and the prefrontal cortex. An intronic single nucleotide polymorphism within the D₂ receptor gene (DRD2) (rs1076560, guanine > thymine or G > T) shifts splicing of the two protein isoforms (D₂ short, mainly presynaptic, and D₂ long) and has been associated with modulation of memory performance and brain activity. Here, our aim was to investigate the association of DRD2 rs1076560 genotype with personality traits of emotional stability and with brain physiology during processing of emotionally relevant stimuli. DRD2 genotype and Big Five Questionnaire scores were evaluated in 134 healthy subjects demonstrating that GG subjects have reduced "emotion control" compared with GT subjects. Functional magnetic resonance imaging in a sample of 24 individuals indicated greater amygdala activity during implicit processing and greater dorsolateral prefrontal cortex (DLPFC) response during explicit processing of facial emotional stimuli in GG subjects compared with GT. Other results also demonstrate an interaction between DRD2 genotype and facial emotional expression on functional connectivity of both amygdala and dorsolateral prefrontal regions with overlapping medial prefrontal areas. Moreover, rs1076560 genotype is associated with differential relationships between amygdala/DLPFC functional connectivity and emotion control scores. These results suggest that genetically determined D₂ signaling may explain part of personality traits related to emotion processing and individual variability in specific brain responses to emotionally relevant inputs.

Psyche is back.

I've been meaning to mention that the official journal of the ASSC ( the Association for the Scientific Study of Consciousness), Psyche, is now back in a new form with its articles available for free PDF download.

Ongoing Victim Suffering Increases Prejudice

Imhoff and Banse empirically test the secondary-anti-Semitism theory, which suggests that every reminder of the German atrocities and the victims' suffering still evokes aversive feelings of guilt and thus increases a defensive anti-Semitism—even in Germans born decades after 1945. (Hence the famous quip from Israeli psychoanalyst Zvi Rex that "The Germans will never forgive the Jews for Auschwitz.") The bogus pipeline (BPL) mentioned is a classic approach for revealing socially undesirable attitudes or behavior in which participants are led to believe that they are being monitored by a psychophysiological apparatus that can detect untruthful responses. Previous research has shown that individuals disclose more socially undesirable behaviors and attitudes under BPL conditions than when the BPL is not employed. Here is the abstract:

Some people have postulated that the perception of Jews' ongoing suffering from past atrocities can result in an increase in anti-Semitism. This postulated secondary anti-Semitism is compatible with a number of psychological theories, but until now there has been no empirical evidence in support of this notion. The present study provides the first evidence that ongoing suffering evokes an increase in prejudice against the victims. However, this effect became apparent only if respondents felt obliged to respond truthfully because of a bogus pipeline (BPL); without this constraint, the perception of ongoing victim suffering led to a socially desirable reduction in self-reported prejudice. The validity of the BPL manipulation was confirmed by the finding that it moderated the relation between explicit and implicit anti-Semitism, as measured with an affect misattribution procedure.

Universality in distinguishing natural from artificial, and in color naming.

Interesting observations by Biederman et al.:

Many of the phenomena underlying shape recognition can be derived from the greater sensitivity to nonaccidental properties of an image (e.g., whether a contour is straight or curved), which are invariant to orientation in depth, than to the metric properties of an image (e.g., a contour's degree of curvature), which can vary with orientation. What enables this sensitivity? One explanation is that it derives from people's immersion in a manufactured world in which simple, regular shapes distinguished by nonaccidental properties abound (e.g., a can, a brick), and toddlers are encouraged to play with toy shape sorters. This report provides evidence against this explanation. The Himba, a seminomadic people living in a remote region of northwestern Namibia where there is little exposure to regular, simple artifacts, were virtually identical to Western observers in their greater sensitivity to nonaccidental properties than to metric properties of simple shapes.

Also, on the subject of human universals, Lindsey and Brown note universal motifs in color naming.

Obama, Afganistan, and the emotional brain

David Eagleman does a nice essay on how Obama's withdrawal timetable decisions relate to the psychology of uncertainty, expectation, and reward.

Watch the live dissection of a famous brain.

See Benedict's Carey's article on Henry Molaison — known during his lifetime only as H.M., to protect his privacy — who lost the ability to form new memories after a brain operation in 1953, and over the next half century became the most studied patient in brain science. Here is the dissection in progress:

We have reached the corpus callosum. The team is resting for the night. The brain will be safe surrounded by our chillers until tomorrow morning. The cutting will resume again at 8AM PST.

Tomorrow will be a big day - We will try to cover the medial temporal lobes and the area surrounding the hippocampus.

Hearing with both your skin and your ears

Gick and Derrick offer a fascinating example of cross modal sensory perception, demonstrating 'aero-tactile' integration in speech perception:

...we show that perceivers integrate naturalistic tactile information during auditory speech perception without previous training. Drawing on the observation that some speech sounds produce tiny bursts of aspiration (such as English 'p'), we applied slight, inaudible air puffs on participants' skin at one of two locations: the right hand or the neck. Syllables heard simultaneously with cutaneous air puffs were more likely to be heard as aspirated (for example, causing participants to mishear 'b' as 'p'). These results demonstrate that perceivers integrate event-relevant tactile information in auditory perception in much the same way as they do visual information.

The syllables included “pa” and “ta,” which produce a brief puff from the mouth when spoken, and “da” and “ba,” which do not produce puffs. When listeners heard “da” or “ba” while a puff of air was blown onto their skin, they perceived the sound as “ta” or “pa.” It seems likely that this integration of different sensory cues is innate, for subjects were completely unaware that they were doing it.

Buttress self esteem - reduce aggression

Here is a fascinating study from Thomaes et al. They conducted a randomized field trial in the Netherlands to assess the efficacy of a brief affirmation exercise designed to buttress self-esteem. Before the intervention, aggressive behavior was prevalent among the individuals who scored high on the narcissism scale and low on self-esteem. Afterward, acts of aggression decreased even though the individual levels of self-esteem (both high and low) were unchanged. Here is the abstract:

Narcissistic individuals are prone to become aggressive when their egos are threatened. We report a randomized field experiment that tested whether a social-psychological intervention designed to lessen the impact of ego threat reduces narcissistic aggression. A sample of 405 young adolescents (mean age = 13.9 years) were randomly assigned to complete either a short self-affirmation writing assignment (which allowed them to reflect on their personally important values) or a control writing assignment. We expected that the self-affirmation would temporarily attenuate the ego-protective motivations that normally drive narcissists' aggression. As expected, the self-affirmation writing assignment reduced narcissistic aggression for a period of a school week, that is, for a period up to 400 times the duration of the intervention itself. These results provide the first empirical demonstration that buttressing self-esteem (as opposed to boosting self-esteem) can be effective at reducing aggression in at-risk youth.

How's Your Gaydar?

From the random samples section of the Nov. 27 issue of Science:

Can you guess a woman's sexual orientation just from her face? Surprisingly, your guess would be better than flipping a coin....Psychologist Nicholas Rule of Tufts University in Medford, Massachusetts, and colleagues asked 21 college students the same question about 192 photos—cropped to eliminate hair and ears—of gay and straight women from dating Web sites. The undergraduates guessed right 64% of the time and scored better than chance—53%—even when they saw only the women's eyes, the researchers report this month in the Journal of Experimental Social Psychology. In 2008, Rule reported similar results with male faces.

The process appears to be unconscious, Rule says. Subjects were more accurate when told to make snap judgments than when they pondered their decisions. Rule believes subtle differences in facial muscles caused by habitual expressions may be the clue. Previous work has shown that homosexuals tend to adopt facial expressions more typical of the opposite sex. The results show that we know much more about others from snippets of information than we realize, says psychologist David Kenny of the University of Connecticut, Storrs.

Here is the abstract from Rule et al.

Whereas previous work has shown that male sexual orientation can be accurately and rapidly perceived from the human face and its individual features, no study has examined the judgment of female sexual orientation. To fill this gap, the current work examined the accuracy, speed, and automaticity of judgments of female sexual orientation from the face and from facial features. Study 1 showed that female sexual orientation could be accurately judged from the face and from just eyes without brows and limited to the outer canthi. Study 2 then examined the speed and efficiency of these judgments, showing that judgments of the faces following very brief, near subliminal (40 ms) exposures were significantly better than chance guessing. Finally, Study 3 tested the automaticity of judgments of female sexual orientation by examining the effects of deliberation on accuracy. Participants who made snap judgments of female sexual orientation were significantly more accurate than participants who made thoughtful and deliberated judgments. These data therefore evidence a robust, reliable, and automatic capacity for extracting information about female sexual orientation from nonverbal cues in the face.

Dietary specialization: man-eating lions

I thought this fascinating bit of work was a hoot. Two famous man-eating lions in the Tsavo region of Kenya were identified and shot in 1989, and these guys analyzed their diet from studies of the isotopes in their bones:

Cooperation is the cornerstone of lion social behavior. In a notorious case, a coalition of two adult male lions from Tsavo, southern Kenya, cooperatively killed dozens of railway workers in 1898. The “man-eaters of Tsavo” have since become the subject of numerous popular accounts, including three Hollywood films. Yet the full extent of the lions' man-eating behavior is unknown; estimates range widely from 28 to 135 victims. Here we use stable isotope ratios to quantify increasing dietary specialization on novel prey during a time of food limitation. For one lion, the δ¹³C and δ¹⁵N values of bone collagen and hair keratin (which reflect dietary inputs over years and months, respectively) reveal isotopic changes that are consistent with a progressive dietary specialization on humans. These findings not only support the hypothesis that prey scarcity drives individual dietary specialization, but also demonstrate that sustained dietary individuality can exist within a cooperative framework. The intensity of human predation (up to 30% reliance during the final months of 1898) is also associated with severe craniodental infirmities, which may have further promoted the inclusion of unconventional prey under perturbed environmental conditions.



The man-eaters of Tsavo and a Taita ancestral shrine. (A) Lieutenant Colonel J. H. Patterson and lion FMNH 23970 shot December 9, 1898 (16) (FMNH photo archives no. z93658, Field Museum of Natural History). (B) Articulated jaws of FMNH 23970 revealing a fractured lower right canine (and subsequent root-tip abscess), missing lower incisors, supererupted upper right incisors, and rotation and malocclusion of the upper right canine. Cranial asymmetry of 23970 occurred after injury and before death. (C) Lion FMNH 23969 shot December 29, 1898. (D) Articulated jaws of FMNH 23969, revealing a fractured upper left carnassial with a double pulp exposure. (E) A Taita ancestral shrine photographed in 1929 by L. S. B. Leakey. Such a shrine results from the unusual funerary practices of the Taita; after approximately 1 year of burial in a seated position, skulls are exhumed, severed, and enshrined in ancestral caves or rock shelters.

Facial plus vocal emotion - watching the brain's enhanced response

From Hagan et al:

An influential neural model of face perception suggests that the posterior superior temporal sulcus (STS) is sensitive to those aspects of faces that produce transient visual changes, including facial expression. Other researchers note that recognition of expression involves multiple sensory modalities and suggest that the STS also may respond to crossmodal facial signals that change transiently. Indeed, many studies of audiovisual (AV) speech perception show STS involvement in AV speech integration. Here we examine whether these findings extend to AV emotion. We used magnetoencephalography to measure the neural responses of participants as they viewed and heard emotionally congruent fear and minimally congruent neutral face and voice stimuli. We demonstrate significant supra-additive responses (i.e., where AV > [unimodal auditory + unimodal visual]) in the posterior STS within the first 250 ms for emotionally congruent AV stimuli. These findings show a role for the STS in processing crossmodal emotive signals.

Dieting, compulsive eating, and brain stress.

An interesting piece from Cottone et al:

Dieting to control body weight involves cycles of deprivation from palatable food that can promote compulsive eating. The present study shows that rats withdrawn from intermittent access to palatable food exhibit overeating of palatable food upon renewed access and an affective withdrawal-like state characterized by corticotropin-releasing factor-1 (CRF1) receptor antagonist-reversible behaviors, including hypophagia, motivational deficits to obtain less palatable food, and anxiogenic-like behavior. Withdrawal was accompanied by increased CRF expression and CRF1 electrophysiological responsiveness in the central nucleus of the amygdala. We propose that recruitment of anti-reward extrahypothalamic CRF-CRF1 systems during withdrawal from palatable food, analogous to abstinence from abused drugs, may promote compulsive selection of palatable food, undereating of healthier alternatives, and a negative emotional state when intake of palatable food is prevented.

Neural architecture of music-evoked autobiographical memories

Interesting work (open access article) from Janata:

The medial prefrontal cortex (MPFC) is regarded as a region of the brain that supports self-referential processes, including the integration of sensory information with self-knowledge and the retrieval of autobiographical information. I used functional magnetic resonance imaging and a novel procedure for eliciting autobiographical memories with excerpts of popular music dating to one's extended childhood to test the hypothesis that music and autobiographical memories are integrated in the MPFC. Dorsal regions of the MPFC (Brodmann area 8/9) were shown to respond parametrically to the degree of autobiographical salience experienced over the course of individual 30 s excerpts. Moreover, the dorsal MPFC also responded on a second, faster timescale corresponding to the signature movements of the musical excerpts through tonal space. These results suggest that the dorsal MPFC associates music and memories when we experience emotionally salient episodic memories that are triggered by familiar songs from our personal past. MPFC acted in concert with lateral prefrontal and posterior cortices both in terms of tonality tracking and overall responsiveness to familiar and autobiographically salient songs. These findings extend the results of previous autobiographical memory research by demonstrating the spontaneous activation of an autobiographical memory network in a naturalistic task with low retrieval demands.

Neural correlates of detecting wrong notes in advance.

I'm always fascinating by studies on the brains of pianists (like myself). This from Ruiz et al:

Music performance is an extremely rapid process with low incidence of errors even at the fast rates of production required. This is possible only due to the fast functioning of the self-monitoring system. Surprisingly, no specific data about error monitoring have been published in the music domain. Consequently, the present study investigated the electrophysiological correlates of executive control mechanisms, in particular error detection, during piano performance. Our target was to extend the previous research efforts on understanding of the human action-monitoring system by selecting a highly skilled multimodal task. Pianists had to retrieve memorized music pieces at a fast tempo in the presence or absence of auditory feedback. Our main interest was to study the interplay between auditory and sensorimotor information in the processes triggered by an erroneous action, considering only wrong pitches as errors. We found that around 70 ms prior to errors a negative component is elicited in the event-related potentials and is generated by the anterior cingulate cortex. Interestingly, this component was independent of the auditory feedback. However, the auditory information did modulate the processing of the errors after their execution, as reflected in a larger error positivity (Pe). Our data are interpreted within the context of feedforward models and the auditory–motor coupling.

Nutrition, brain aging, and neurodegeneration

Joseph et al. offer a review of recent work showing that dietary changes favoring berry fruit, nut, fish oil, and curcumin intake, as well as and caloric restriction mimetics (such as resveratrol) may provide beneficial effects in aging and prevent or delay the onset of neurodegenerative diseases such as Alzheimer disease. While many of the mechanisms for the beneficial effects of these nutritional interventions have yet to be discerned, it is clear that they involve decreases in oxidative/inflammatory stress signaling, increases in protective signaling, and may even involve hormetic effects to protect against the two major villains of aging, oxidative and inflammatory stressors. (Hormetic is a term used to describe generally-favorable biological responses to low exposures to toxins and other stressors.)

The fMRI of understanding others' regret.

Rizzolatti and colleagues carry the mirror neuron story to an even higher level in a study of regret:

Previous studies showed that the understanding of others' basic emotional experiences is based on a “resonant” mechanism, i.e., on the reactivation, in the observer's brain, of the cerebral areas associated with those experiences. The present study aimed to investigate whether the same neural mechanism is activated both when experiencing and attending complex, cognitively-generated, emotions. A gambling task and functional-Magnetic-Resonance-Imaging (fMRI) were used to test this hypothesis using regret, the negative cognitively-based emotion resulting from an unfavorable counterfactual comparison between the outcomes of chosen and discarded options. Do the same brain structures that mediate the experience of regret become active in the observation of situations eliciting regret in another individual? Here we show that observing the regretful outcomes of someone else's choices activates the same regions that are activated during a first-person experience of regret, i.e. the ventromedial prefrontal cortex, anterior cingulate cortex and hippocampus. These results extend the possible role of a mirror-like mechanism beyond basic emotions.

The religious wars

In a NYTimes OpEd piece appropriate to yesterday's Thanksgiving rituals Kristof notes a new crop of books on religion that that he feels are less combative and more thoughtful than extreme fundamentalist (The "Left Behind" novels) or atheist (Dawkins, Harris, Hitchens) efforts.

One of these is “The Evolution of God,” by Robert Wright, who explores how religions have changed — improved — over the millennia. He notes that God, as perceived by humans, has mellowed from the capricious warlord sometimes depicted in the Old Testament who periodically orders genocides...Karen Armstrong’s “The Case for God,” likewise doesn’t posit a Grandpa-in-the-Sky; rather, she sees God in terms of an ineffable presence that can be neither proven nor disproven in any rational sense. To Ms. Armstrong, faith belongs to the realm of life’s mysteries, beyond the world of reason, and people on both sides of the “God gap” make the mistake of interpreting religious traditions too literally...“The Faith Instinct,” by...Nicholas Wade, suggests a reason for the durability of faith: humans may be programmed for religious belief, because faith conferred evolutionary advantages in primitive times. That doesn’t go to the question of whether God exists, but it suggests that religion in some form may be with us for eons to come.

Openness versus conservatism - its cultural evolution

Acerbi et al. ask what might make different groups of people more liberal or conservative (or open minded versus having inflexible views), and develop a model which shows that cultural evolution can maintain openness to new information as well as effectiveness at cultural transmission. They consider how rules of cultural transmission can be modified by social learning. For example, individuals might learn from others whether or not to rely on social information. Their model predicts smaller societies to be more conservative, which agrees with the observation that traditional societies (whose very name implies conservatism) tend to be small. It is consistent with archaeological evidence showing that large cultural repertoires can be maintained only by large groups.

We present a model of cultural evolution in which an individual's propensity to engage in social learning is affected by social learning itself. We assume that individuals observe cultural traits displayed by others and decide whether to copy them based on their overall preference for the displayed traits. Preferences, too, can be transmitted between individuals. Our results show that such cultural dynamics tends to produce conservative individuals, i.e., individuals who are reluctant to copy new traits. Openness to new information, however, can be maintained when individuals need significant time to acquire the cultural traits that make them effective cultural models. We show that a gradual enculturation of young individuals by many models and a larger cultural repertoire to be acquired are favorable circumstances for the long-term maintenance of openness in individuals and groups. Our results agree with data about lifetime personality change, showing that openness to new information decreases with age. Our results show that cultural remodeling of cultural transmission is a powerful force in cultural evolution, i.e., that cultural evolution can change its own dynamics.

Deconstructing the Placebo

I want to point you to this great post at Neuroskeptic. Here is its ending text:

"The placebo effect" has become a vague catch-all term for anything that seems to happen to people when you give them a sugar pill. Of course, lots of things could happen. They could feel better just because of the passage of time. Or they could realize that they're supposed to feel better and say they feel better, even if they don't.

The "true" placebo effect refers to improvement (or worsening) of symptoms driven purely by the psychological expectation of such. But even this is something of a catch-all term. Many things could drive this improvement. Suppose you give someone a placebo pill that you claim will make them more intelligent, and they believe it.

Believing themselves to be smarter, they start doing smart things like crosswords, math puzzles, reading hard books (or even reading Neuroskeptic), etc. But the placebo itself was just a nudge in the right direction. Anything which provided that nudge would also have worked - and the nudge itself can't take all the credit.

The strongest meaning of the "placebo effect" is a direct effect of belief upon symptoms. You give someone a sugar pill or injection, and they immediately feel less pain, or whatever. But even this effect encompasses two kinds of things. It's one thing if the original symptoms have a "real" medical cause, like a broken leg. But it's another thing if the original symptoms are themselves partially or wholly driven by psychological factors, i.e. if they are "psychosomatic".

If a placebo treats a "psychosomatic" disease, then that's not because the placebo has some mysterious, mind-over-matter "placebo effect". All the mystery, rather, lies with the psychosomatic disease. But this is a crucial distinction.

People seem more willing to accept the mind-over-matter powers of "the placebo" than they are to accept the existence of psychosomatic illness. As if only doctors with sugar pills possess the power of suggestion. If a simple pill can convince someone that they are cured, surely the modern world in all its complexity could convince people that they're ill.

Watching our brains judge gain versus pain

Yet another lucidly presented bit of work from a collaboration involving Dolan's group at University College London:

The maxim "no pain, no gain" summarizes scenarios in which an action leading to reward also entails a cost. Although we know a substantial amount about how the brain represents pain and reward separately, we know little about how they are integrated during goal-directed behavior. Two theoretical models might account for the integration of reward and pain. An additive model specifies that the disutility of costs is summed linearly with the utility of benefits, whereas an interactive model suggests that cost and benefit utilities interact so that the sensitivity to benefits is attenuated as costs become increasingly aversive. Using a novel task that required integration of physical pain and monetary reward, we examined the mechanism underlying cost–benefit integration in humans. We provide evidence in support of an interactive model in behavioral choice. Using functional neuroimaging, we identify a neural signature for this interaction such that, when the consequences of actions embody a mixture of reward and pain, there is an attenuation of a predictive reward signal in both ventral anterior cingulate cortex and ventral striatum. We conclude that these regions subserve integration of action costs and benefits in humans, a finding that suggests a cross-species similarity in neural substrates that implement this function and illuminates mechanisms that underlie altered decision making under aversive conditions.

Curing musicians' dystonia.

Here is another bit on music or musicians. (I seem to be doing a fair number of postings in this area, maybe because I'm back into more hard core piano playing since returning to Fort Lauderdale...my hands are fatigued after 3 hours of Dvorak and Dohnanyi piano quintets yesterday.) Rosenkranz et al. show that an overly expanded spatial integration of proprioceptive input into the hand motor cortex that can cause deficiencies in hand motor controls (dystonia) can be reversed by proprioceptive training in pianists with musician's dystonia to the pattern seen in healthy pianists. (The training intervention requires the subject's attention to be focused for 15 min on random vibrations delivered to three hand muscles.):

Professional musicians are an excellent model of long-term motor learning effects on structure and function of the sensorimotor system. However, intensive motor skill training has been associated with task-specific deficiency in hand motor control, which has a higher prevalence among musicians (musician's dystonia) than in the general population. Using a transcranial magnetic stimulation paradigm, we previously found an expanded spatial integration of proprioceptive input into the hand motor cortex [sensorimotor organization (SMO)] in healthy musicians. In musician's dystonia, however, this expansion was even larger. Whereas motor skills of musicians are likely to be supported by a spatially expanded SMO, we hypothesized that in musician's dystonia this might have developed too far and now disrupts rather than assists task-specific motor control. If so, motor control should be regained by reversing the excessive reorganization in musician's dystonia. Here, we test this hypothesis and show that a 15 min intervention with proprioceptive input (proprioceptive training) restored SMO in pianists with musician's dystonia to the pattern seen in healthy pianists. Crucially, task-specific motor control improved significantly and objectively as measured with a MIDI (musical instrument digital interface) piano, and the amount of behavioral improvement was significantly correlated to the degree of sensorimotor reorganization. In healthy pianists and nonmusicians, the SMO and motor performance remained essentially unchanged. These findings suggest that the differentiation of SMO in the hand motor cortex and the degree of motor control of intensively practiced tasks are significantly linked and finely balanced. Proprioceptive training restored this balance in musician's dystonia to the behaviorally beneficial level of healthy musicians.

More on the trust and empathy hormone...

Natalie Angier does a summary of some recent studies on oxytocin, several of which I've already mentioned in MindBlog posts (enter oxytocin in the search box to list them). Of particular interest is recent work from Keltner's group showing that genetic differences in people’s responsiveness to the effects of oxytocin are linked to their ability to read faces, infer the emotions of others, feel distress at others’ hardship and even to identify with characters in a novel. Here is the abstract from the Keltner group:

Oxytocin, a peptide that functions as both a hormone and neurotransmitter, has broad influences on social and emotional processing throughout the body and the brain. In this study, we tested how a polymorphism (rs53576) of the oxytocin receptor relates to two key social processes related to oxytocin: empathy and stress reactivity. Compared with individuals homozygous for the G allele of rs53576 (GG), individuals with one or two copies of the A allele (AG/AA) exhibited lower behavioral and dispositional empathy, as measured by the “Reading the Mind in the Eyes” Test and an other-oriented empathy scale. Furthermore, AA/AG individuals displayed higher physiological and dispositional stress reactivity than GG individuals, as determined by heart rate response during a startle anticipation task and an affective reactivity scale. Our results provide evidence of how a naturally occurring genetic variation of the oxytocin receptor relates to both empathy and stress profiles.

Origins of empathetic yawning?

Interesting observations by Palagi et al:

Yawn contagion in humans has been proposed to be related to our capacity for empathy. It is presently unclear whether this capacity is uniquely human or shared with other primates, especially monkeys. Here, we show that in gelada baboons (Theropithecus gelada) yawning is contagious between individuals, especially those that are socially close, i.e., the contagiousness of yawning correlated with the level of grooming contact between individuals. This correlation persisted after controlling for the effect of spatial association. Thus, emotional proximity rather than spatial proximity best predicts yawn contagion. Adult females showed precise matching of different yawning types, which suggests a mirroring mechanism that activates shared representations. The present study also suggests that females have an enhanced sensitivity and emotional tuning toward companions. These findings are consistent with the view that contagious yawning reveals an emotional connection between individuals. This phenomenon, here demonstrated in monkeys, could be a building block for full-blown empathy.

Three different yawning displays performed by gelada baboons. Covered teeth yawning (left) uncovered teeth yawning (middle). and uncovered gums yawning (right).

Sounds during sleep aid memory

Rudoy et al. (PDF here) find that if, while asleep, people hear sounds that had earlier been associated with objects at specific spatial locations, upon waking they recalled these locations more accurately than other locations for which no reminder cues were provided. Consolidation thus operates during sleep with high specificity and is subject to systematic influences through simple auditory stimulation.

The Music Instinct

Steven Mithen (author of The Singing Neanderthals) does a summary of his ideas on the evolutionary basis of musicality in this open access article in the Annals of the New York Academy of Sciences.

Why does music pervade our lives and those of all known human beings living today and in the recent past? Why do we feel compelled to engage in musical activity, or at least simply enjoy listening to music even if we choose not to actively participate? I argue that this is because musicality—communication using variations in pitch, rhythm, dynamics and timbre, by a combination of the voice, body (as in dance), and material culture—was essential to the lives of our pre-linguistic hominin ancestors. As a consequence we have inherited a desire to engage with music, even if this has no adaptive benefit for us today as a species whose communication system is dominated by spoken language. In this article I provide a summary of the arguments to support this view.

Musicians are not as bothered by background noise.

From Parbery-Clark et al.:

Musicians have lifelong experience parsing melodies from background harmonies, which can be considered a process analogous to speech perception in noise. To investigate the effect of musical experience on the neural representation of speech-in-noise, we compared subcortical neurophysiological responses to speech in quiet and noise in a group of highly trained musicians and nonmusician controls. Musicians were found to have a more robust subcortical representation of the acoustic stimulus in the presence of noise. Specifically, musicians demonstrated faster neural timing, enhanced representation of speech harmonics, and less degraded response morphology in noise. Neural measures were associated with better behavioral performance on the Hearing in Noise Test (HINT) for which musicians outperformed the nonmusician controls. These findings suggest that musical experience limits the negative effects of competing background noise, thereby providing the first biological evidence for musicians' perceptual advantage for speech-in-noise.

Imagination and bad governance

I liked this column by Thomas Friedman. Some clips:

...I’m not ready to cede the 21st century to China just yet...there are still two really important things that can’t be commoditized. Fortunately, America still has one of them: imagination...Who would cede a century in which imagination will have such a high value to an authoritarian society that controls its Internet and jails political prisoners?

But while our culture of imagination is still vibrant, the other critical factor that still differentiates countries today — and is not a commodity — is good governance, which can harness creativity. And that we may be losing. Why? Because at least six things have come together to fracture our public space and paralyze our ability to forge optimal solutions:

1) Money in politics has become so pervasive that lawmakers have to spend most of their time raising it, selling their souls to those who have it or defending themselves from the smallest interest groups with deep pockets that can trump the national interest.

2) The gerrymandering of political districts means politicians of each party can now choose their own voters and never have to appeal to the center.

3) The cable TV culture encourages shouting and segregating people into their own political echo chambers.

4) A permanent presidential campaign leaves little time for governing.

5) The Internet, which, at its best, provides a check on elites and establishments and opens the way for new voices and, which, at its worst provides a home for every extreme view and spawns digital lynch mobs from across the political spectrum that attack anyone who departs from their specific orthodoxy.

6) A U.S. business community that has become so globalized that it only comes to Washington to lobby for its own narrow interests; it rarely speaks out anymore in defense of national issues like health care, education and open markets.

And, while I'm passing on interesting New York Times pieces, this one on economic recovery viewed as self fulfilling prophecy.

Neural predictors of attitude changes.

Some work from van Veen et al. on attitude changes induced by cognitive dissonance:

When our actions conflict with our prior attitudes, we often change our attitudes to be more consistent with our actions. This phenomenon, known as cognitive dissonance, is considered to be one of the most influential theories in psychology. However, the neural basis of this phenomenon is unknown. Using a Solomon four-group design, we scanned participants with functional MRI while they argued that the uncomfortable scanner environment was nevertheless a pleasant experience. We found that cognitive dissonance engaged the dorsal anterior cingulate cortex and anterior insula; furthermore, we found that the activation of these regions tightly predicted participants' subsequent attitude change. These effects were not observed in a control group. Our findings elucidate the neural representation of cognitive dissonance, and support the role of the anterior cingulate cortex in detecting cognitive conflict and the neural prediction of attitude change.

Why sex matters - more on brain differences between men and women

Luders et al. examine brain differences not dependent on size in gray matter distributions between men and women. They find a number of regions where matched women had significantly larger gray matter (GM) volumes than in matched men, suggesting that anatomical differences between male and female brains exist independently of brain size effects. While they did not detect any regions of larger GM volume in men than in women, there were a number of regions indicating larger GM volumes in women than in men. Comparing men and women with identical brain sizes, they detected the largest clusters in the right and left caudate extending into adjacent regions of the basal ganglia, as well as into the left orbitofrontal region. These findings appear to disagree with previous findings indicating that brain volume (rather than sex) is the main variable accounting for differences in gray matter proportion. Their abstract:

The different brain anatomy of men and women is both a classic and continuing topic of major interest. Among the most replicated and robust sex differences are larger overall brain dimensions in men, and relative increases of global and regional gray matter (GM) in women. However, the question remains whether sex-typical differences in brain size (i.e., larger male and smaller female brains) or biological sex itself account for the observed sex effects on tissue amount and distribution. Exploring cerebral structures in men and women with similar brain size may clarify the true contribution of biological sex. We thus examined a sample of 24 male and 24 female subjects with brains identical in size, in addition to 24 male and 24 female subjects with considerable brain size differences. Using this large set of brains (n = 96), we applied a well validated and automated voxel-based approach to examine regional volumes of GM. While we revealed significant main effects of sex, there were no significant effects of brain size (and no significant interactions between sex and brain size). When conducting post hoc tests, we revealed a number of regions where women had larger GM volumes than men. Importantly, these sex effects remained evident when comparing men and women with the same brain size. Altogether, our findings suggest that the observed increased regional GM volumes in female brains constitute sex-dependent redistributions of tissue volume, rather than individual adjustments attributable to brain size.