Oxytocin dilates our pupils and enhances emotion detection

Interesting work from Leknes et al.:

Sensing others’ emotions through subtle facial expressions is a highly important social skill. We investigated the effects of intranasal oxytocin treatment on the evaluation of explicit and ‘hidden’ emotional expressions and related the results to individual differences in sensitivity to others’ subtle expressions of anger and happiness. Forty healthy volunteers participated in this double-blind, placebo-controlled crossover study, which shows that a single dose of intranasal oxytocin (40 IU) enhanced or ‘sharpened’ evaluative processing of others’ positive and negative facial expression for both explicit and hidden emotional information. Our results point to mechanisms that could underpin oxytocin’s prosocial effects in humans. Importantly, individual differences in baseline emotional sensitivity predicted oxytocin’s effects on the ability to sense differences between faces with hidden emotional information. Participants with low emotional sensitivity showed greater oxytocin-induced improvement. These participants also showed larger task-related pupil dilation, suggesting that they also allocated the most attentional resources to the task. Overall, oxytocin treatment enhanced stimulus-induced pupil dilation, consistent with oxytocin enhancement of attention towards socially relevant stimuli. Since pupil dilation can be associated with increased attractiveness and approach behaviour, this effect could also represent a mechanism by which oxytocin increases human affiliation.

Our sense of fairness changes with weak electric stimulation of our prefrontal cortex.

Fascinating work from Ruff et al:

All known human societies have maintained social order by enforcing compliance with social norms. The biological mechanisms underlying norm compliance are, however, hardly understood. We show that the right lateral prefrontal cortex (rLPFC) is involved in both voluntary and sanction-induced norm compliance. Both types of compliance could be changed by varying neural excitability of this brain region with transcranial direct current stimulation, but they were affected in opposite ways, suggesting that the stimulated region plays a fundamentally different role in voluntary and sanction-based compliance. Brain stimulation had a particularly strong effect for compliance based on socially constituted sanctions, while it left beliefs about what the norm prescribes and about subjectively expected sanctions unaffected. Our findings suggest that rLPFC activity is a key biological prerequisite for an evolutionarily and socially important aspect of human behavior.

(Culotta does a brief review here.)

Psychedelic drugs cause cortical desynchronization

From Muthukumaraswamy et al., small wonder that it doesn't all hang together during the psychedelic experience:

Psychedelic drugs produce profound changes in consciousness, but the underlying neurobiological mechanisms for this remain unclear. Spontaneous and induced oscillatory activity was recorded in healthy human participants with magnetoencephalography after intravenous infusion of psilocybin—prodrug of the nonselective serotonin 2A receptor agonist and classic psychedelic psilocin. Psilocybin reduced spontaneous cortical oscillatory power from 1 to 50 Hz in posterior association cortices, and from 8 to 100 Hz in frontal association cortices. Large decreases in oscillatory power were seen in areas of the default-mode network. Independent component analysis was used to identify a number of resting-state networks, and activity in these was similarly decreased after psilocybin. Psilocybin had no effect on low-level visually induced and motor-induced gamma-band oscillations, suggesting that some basic elements of oscillatory brain activity are relatively preserved during the psychedelic experience. Dynamic causal modeling revealed that posterior cingulate cortex desynchronization can be explained by increased excitability of deep-layer pyramidal neurons, which are known to be rich in 5-HT2A receptors. These findings suggest that the subjective effects of psychedelics result from a desynchronization of ongoing oscillatory rhythms in the cortex, likely triggered by 5-HT2A receptor-mediated excitation of deep pyramidal cells.

Poulenc Improvisation No. 15

This piece is a homage to Edith Piaf.  The last of a series of Poulenc recordings I have done this year.

 

Better memory with less default mode activity

I've done a number of posts on our default mode versus attentional networks (a review is here, for example). Here is the summary and abstract for some interesting work in NeuroImage by Chai et al. on the relationship of these modes to memory:

Highlights:

-Children, adolescents and adults studied scenes during fMRI.
-Default-mode network (DMN) deactivation was examined during memory encoding.
-DMN deactivation was associated with successful memory encoding in adults.
-In children, deactivation of the DMN did not predict memory outcome. 

Abstract:

Task-induced deactivation of the default-mode network (DMN) has been associated in adults with successful episodic memory formation, possibly as a mechanism to focus allocation of mental resources for successful encoding of external stimuli. We investigated developmental changes of deactivation of the DMN (posterior cingulate, medial prefrontal, and bilateral lateral parietal cortices) during episodic memory formation in children, adolescents, and young adults (ages 8–24), who studied scenes during functional magnetic resonance imaging (fMRI). Recognition memory improved with age. We defined DMN regions of interest from a different sample of participants with the same age range, using resting-state fMRI. In adults, there was greater deactivation of the DMN for scenes that were later remembered than scenes that were later forgotten. In children, deactivation of the default-network did not differ reliably between scenes that were later remembered or forgotten. Adolescents exhibited a pattern of activation intermediate to that of children and adults. The hippocampal region, often considered part of the DMN, showed a functional dissociation with the rest of the DMN by exhibiting increased activation for later remembered than later forgotten scene that was similar across age groups. These findings suggest that development of memory ability from childhood through adulthood may involve increased deactivation of the neocortical DMN during learning.

Evilicious humans, hard-wired for war?

"Evilicious" is the title of a new book self published by Marc Hauser, the Harvard Psychologist forced to resign his position after it was discovered that he had been falsifying behavioral data to fit his foregone conclusions. He asks "why seemingly normal people torture, mutilate, and kill others for the fun of it — or for no apparent benefit at all." He suggests that humans uniquely evolved this capacity because "evildoers emerge when unsatisfied desires combine with the denial of reality, enabling individuals to engage in gratuitous cruelty toward innocent victims. This simple recipe is part of human nature, and part of our brain’s uniquely evolved capacity to combine different thoughts and emotions." Hauser's 'trying for a second chance' book has drawn a number of favorable reviews. One summary from Atran's review cited by Dobbs:

....“addiction to evil” – the persistent subjection of innocents to gratuitous cruelty — emerged as a by-product of the human brain’s unique evolutionary design. The ability to creatively combine all manner of thought and emotion enabled our species to produce great works of art and science, as well as to freely choose to kill and torture with a level of maliciousness unprecedented in the history of life on earth. Here we find that the most dangerous and effective evildoers are not sadists or serial killers with disordered minds, but mostly normal people who could have chosen not to kill and torture. When driven by unsatisfied desires — especially if channeled into dreams of glory for a cause — and in denying the reality and the humanity of others, even nice guys can become massively bloodthirsty.

A related issue is whether we are "hard-wired for war". Evolutionary biologist David Barash argues there is no convincing evidence for this. Despite examples such as Yanomamo ferocity, a broad survey shows that peacemaking is, if anything, more pronounced and widely distributed, especially among groups of nomadic foragers who are probably closest in ecological circumstance to our hominin ancestors.

Information sharing as a measure of brain consciousness

King et al. make measurements they suggest are a signature of conscious state in awake but noncommunicating patients. I pass on the summary, abstract, and one of their figures (and, the first graphic, thanks to Jean-Rémi King, who offers the unedited PDF of the article here):

Highlights
 • Theories of consciousness link conscious access to global information integration
 • 181 EEG recordings were acquired, including 143 from VS and MCS patients
 • Information sharing across current sources was estimated with a new measure
 • The results suggest that unconscious patients have lower global information sharing

Summary

Neuronal theories of conscious access tentatively relate conscious perception to the integration and global broadcasting of information across distant cortical and thalamic areas. Experiments contrasting visible and invisible stimuli support this view and suggest that global neuronal communication may be detectable using scalp electroencephalography (EEG). However, whether global information sharing across brain areas also provides a specific signature of conscious state in awake but noncommunicating patients remains an active topic of research. We designed a novel measure termed “weighted symbolic mutual information” (wSMI) and applied it to 181 high-density EEG recordings of awake patients recovering from coma and diagnosed in various states of consciousness. The results demonstrate that this measure of information sharing systematically increases with consciousness state, particularly across distant sites. This effect sharply distinguishes patients in vegetative state (VS), minimally conscious state (MCS), and conscious state (CS) and is observed regardless of etiology and delay since insult. The present findings support distributed theories of conscious processing and open up the possibility of an automatic detection of conscious states, which may be particularly important for the diagnosis of awake but noncommunicating patients.

Figure - wSMI Increases with Consciousness, Primarily over Centroposterior Regions(A) The median wSMI that each EEG channel shares with all other channels is depicted for each state of consciousness.(B) 120 pairs formed by 16 clusters of EEG channels are depicted as 3D arcs whose height is proportional to the Euclidian distance separating the two clusters. Line color and thickness are proportional to the mean wSMI shared by the corresponding cluster pair.

Early emergence of mature brain alarm circuits in maternally deprived children

Many studies have shown adverse effects of various kinds of childhood deprivation or abuse, with maternal deprivation being one of the most significant. Normally, medial prefrontal cortex (mPFC) connections with the amygdala are immature during childhood and become adult-like during adolescence. Gee et al. show that institutionalized youths who experienced early maternal deprivation show mature connectivity at a much earlier age:

Early adversity has profound and lasting effects on neurodevelopment and emotional behavior. Under typical environmental conditions, prefrontal cortex connections with the amygdala are immature during childhood and become adult-like during adolescence. Rodent models show that maternal deprivation accelerates this development as an ontogenetic adaptation to adversity. Here, we demonstrate that, as in the rodent, children who experienced early maternal deprivation exhibit early emergence of mature amygdala–prefrontal connectivity. Evidence suggests that the adult-like neural phenotype, which is mediated by cortisol levels, confers some degree of enhanced emotion regulation, as maternally deprived youths with adult-like phenotypes are less anxious than their counterparts with immature phenotypes. Accelerated amygdala–prefrontal development may serve as an ontogenetic adaptation in the human in response to early adversity. 

Francis Poulenc Sonata for piano 4 hands

Here is the last of the 4 hands pieces offered at a recent house concert/social at my Twin Valley Rd. home in Middleton,WI.

Threads of current debate: narcissism, ills of the world, scientism, brain science

I want to pass on some of the products of my TOC (tables of contents) scanning that I’m unlikely to develop into full posts, but that might be of interest to some readers.

Quenque does a piece focusing on San Diego State University psychologist Jean Twenge, who has compared decades of personality test results to conclude that younger generations are increasingly entitled, self-obsessed and unprepared for the realities of adult life. Critics have questioned her data and her results. A subsequent New York Times invitation for debate on social media and narcissism elicits a number of interesting views.

Novelist Janathan Franzen's extended screed in the Guardian on how the world is drifting towards disaster as we Tweet, Text, and spend has some choice passages, and draws a retort from Clive Thompson, who points out that similar hysteria has accompanied all new technology.

Steven Pinker's article in the New Republic,  "Science Is Not Your Enemy"  has drawn an avalanche of comment.  I've already mentioned one retort by Ross Douthat. Douthat follows this up with a piece on Sam Harris' offer of $20,000 for the best rebuttal of his book on how science can determine human values.  Leon Wieseltier rails against science invading the liberal arts.

In pieces more focused on brain science  Gopnik goes after mindless brain scientists, while Eric Kandel offers a rosy view of the new science of mind.  . 

Aspects of our musical experience.

I want to pass on three recent articles I found interesting. The first is a piece by Kawakami in the New York Times on why we like sad music, sumarizing his article in Frontiers in Psychology. He and his collaborators found that when listening to sad music

...felt emotion did not correspond exactly to perceived emotion. Although the sad music was both perceived and felt as “tragic” (e.g., gloomy, meditative and miserable), the listeners did not actually feel the tragic emotion as much as they perceived it. Likewise, when listening to sad music, the listeners felt more “romantic” emotion (e.g., fascinated, dear and in love) and “blithe” emotion (e.g., merry, animated and feel like dancing) than they perceived. (Glinka's "La Séparation" is one of the pieces used).

They suggest this may have something to do with vicarious emotions:

...when we listen to sad music (or watch a sad movie, or read a sad novel), we are inoculated from any real threat or danger that the music (or movie or novel) represents...If this is true, what we experience when we listen to sad music might be thought of as “vicarious emotions.” Here, there is no object or situation that induces emotion directly, as in regular life. Instead, the vicarious emotions are free from the essential unpleasantness of their genuine counterparts, while still drawing force from the similarity between the two.

The second article, by Leman et al., examines how music can entrain the speed of beat synchronized walking. Subjects walked to the rhythm of different musical pieces all having a tempo of 130 beats per minute and a meter of 4 beats. Some music was "activating" in that it increased stride length and distance covered, while "relaxing music" had the opposite effect. They suggest that recurrent patterns of fluctuation affecting the binary meter strength of the music may entrain the vigor of the movement, a relationship between entrainment and expressiveness that might lead to applications in sports and physical rehabilitation. Finally, Koelsch et al. do an intersting examination of processing of hierarchical syntactic structure in music:

Hierarchical structure with nested nonlocal dependencies is a key feature of human language and can be identified theoretically in most pieces of tonal music. However, previous studies have argued against the perception of such structures in music. Here, we show processing of nonlocal dependencies in music. We presented chorales by J. S. Bach and modified versions in which the hierarchical structure was rendered irregular whereas the local structure was kept intact. Brain electric responses differed between regular and irregular hierarchical structures, in both musicians and nonmusicians. This finding indicates that, when listening to music, humans apply cognitive processes that are capable of dealing with long-distance dependencies resulting from hierarchically organized syntactic structures. Our results reveal that a brain mechanism fundamental for syntactic processing is engaged during the perception of music, indicating that processing of hierarchical structure with nested nonlocal dependencies is not just a key component of human language, but a multidomain capacity of human cognition.

Theory of Mind and the mind of the market

The financial community has been in a striking tizzy over the fact that the Federal Reserve didn't do what they were predicting, i.e. start to dial back on their economic stimulus. The financial community also has not been very good at predicting or knowing when a financial bubble is growing. Perhaps work like this piece by Martino et al. casts some mechanistic light on this. They demonstrate that the ability to infer the intentions and mental states of other individuals (“theory of mind”) biases evaluation when people interact not with individuals but with complex modern institutions like financial markets, contributing to the formation of economics bubbles. Here is their summary:

The ability to infer intentions of other agents, called theory of mind (ToM), confers strong advantages for individuals in social situations. Here, we show that ToM can also be maladaptive when people interact with complex modern institutions like financial markets. We tested participants who were investing in an experimental bubble market, a situation in which the price of an asset is much higher than its underlying fundamental value. We describe a mechanism by which social signals computed in the dorsomedial prefrontal cortex affect value computations in ventromedial prefrontal cortex, thereby increasing an individual’s propensity to ‘ride’ financial bubbles and lose money. These regions compute a financial metric that signals variations in order flow intensity, prompting inference about other traders’ intentions. Our results suggest that incorporating inferences about the intentions of others when making value judgments in a complex financial market could lead to the formation of market bubbles.

Franz Schubert Marches caractéristiques, No. 2

This is second of the three four hands pieces played at a recent house concert at my Twin Valley Rd. home in Middleton, WI.

The joystick years - computer games and grey matter volume

Sian Lewis summarizes work by Kühn and Gallinat:

A new study has used voxel-based morphometry of MRI scans of adult video-game players to investigate whether there is a correlation between grey matter volume and the number of years spent playing video games ('joystick years'). They found that grey matter volume in the entorhinal cortex was altered and that the direction of change was influenced by the type of game played; logic or puzzle games tended to increase entorhinal grey matter volume, whereas action-based games had the opposite effect. Moreover, hippocampal volume was found to be greater in players with more 'joystick years', suggesting positive long-term effects on visual attention and navigation.

Clementi Sonata No. 2 in C for piano four hands

Here is the first of the four hands pieces performed at a concert at my home on Sept. 8.

Compassion - Bridging Practice and Science

Science magazine has an article by Kupferschmidt pointing to the work of Tania Singer, a director at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, who has embarked on an ambitious study involving 160 participants to find out whether meditation can make people more compassionate. He notes that meditation research does not have a very rigorous reputation, and some scientists are skeptical about the work, but Singer — who has long practiced meditation herself—hopes her study will be methodologically rigorous enough to withstand criticism. In 2004 Singer published a landmark paper in Science that showed that bilateral anterior insula (AI), rostral anterior cingulate cortex (ACC), brainstem, and cerebellum were activated when subjects received pain and also by a signal that a loved one experienced pain. AI and ACC activation correlated with individual empathy scores. Singer has just release a free 900-page e-book, entitled "Compassion - Bridging Practice and Science", that is quite amazing. I'm going to spend some time paging through it. Here is one clip from Kupferschmidt's commentary:

Numerous studies have shown that people can be "primed" to think more socially in various ways—from reading simple instructions to holding a warm cup of coffee. In one test, participants who listened to Bob Sinclar's hit song "Love Generation" were more likely to come up with words like "help" than those who listened to Sinclar's less uplifting song "Rock This Party." But Singer isn't interested in words; she wants to train people to act more socially in everyday life. And from personal experience, she believes meditation may be the way to do it. At its most basic, the technique simply involves focusing on a feeling. In one meditation exercise in her study, participants are told to imagine a person they love and to concentrate on positive feelings toward them. "May you be happy. May you be safe and sheltered. May you be healthy. May you live with a light heart," the teacher intones. Like bodybuilders increasing the weights they lift, meditators can intensify their compassionate feelings over time. Expert meditators can go very far, Singer says; rape victims may meditate on feeling compassion for their rapist, for instance. To measure meditation's effects, researchers in the ReSource Project determine the level of the stress hormone cortisol in participants' saliva, test their reaction times, have them fill out questionnaires, and shepherd them through virtual reality worlds while monitoring their heart rate. Each participant's brain is scanned for several hours five times over the course of the study. Participants also play computer games designed to evaluate their compassion level. In one of them, developed with Swiss economist Ernst Fehr, they have to guide a smiley along a winding path that leads to a treasure chest; they have blue or red keys to open gates of the same color. But another smiley is also wandering the screen, on its own quest to another treasure, and players have to decide whether to open gates for it, too. In a preliminary study in 2011, Singer showed that just one day of compassion meditation made people more likely to help the other smiley, whereas 1 day of memory training did not. Singer is also trying to better understand what goes on in the brain when it is feeling compassion. The activation patterns seen in the scanner leave open two possibilities: The feeling could be linked to the neurotransmitter dopamine and the brain's reward circuits (which, among many other things, makes you crave chocolate) or it could be linked to what she calls the affiliation network, which is activated for example when you view a picture of your partner or your own child, and is mediated by the neurotransmitters oxytocin or opioids. Singer admits that pinning down the neurobiology of compassion is difficult because the mental state it corresponds to remains fuzzy. A French Buddhist monk may have a very different concept of compassion than an African doctor or a British businessman, and there's friction between the classic third-person perspective of science and subjective experiences. "But we need the first-person experience as well as the third-person science," she says.

Poulenc Novelette No. 3

Here is the third of the Poulenc Novelettes, based on a theme by Manuel de Falla, a return to a more sonorous style, but with nice dissonances. It is one of the pieces played at a house concert Sept. 8, 2013, using the Steinway B at my Twin Valley Road home in Middleton, WI

Virtues of coffee and coffee shops.

I've been meaning to pass on these two articles that help me justify my addiction to breakfast and noon (but not dinner) coffee. Reynolds reviews a number of studies reporting at coffee consumption correlates with a 10% decrease in mortality over a 13 year period, reduced risk of developing type 2 diabetes and other diseases, and slower progression of dementia or Alzheimer's disease. O'Connor notes studies indicating that creative thinking is enhanced by ambient noise levels typical of a bustling coffee shop. The idea is that extreme quiet tends to sharpen focus, which can prevent thinking in the abstract. Moderate noise levels distract people enough so that they think more broadly. So, when you have been sitting at your keyboard for a long time and are beginning to feel a bit locked in, trying pulling up the coffitivity.com website, and see what it does for you.

Old farts perform more consistenly on cognitive tasks than younger adults.

Schmiedek et al. do a demonstration of something we more or less already knew...

People often attribute poor performance to having bad days. Given that cognitive aging leads to lower average levels of performance and more moment-to-moment variability, one might expect that older adults should show greater day-to-day variability and be more likely to experience bad days than younger adults. However, both researchers and ordinary people typically sample only one performance per day for a given activity. Hence, the empirical basis for concluding that cognitive performance does substantially vary from day to day is inadequate. On the basis of data from 101 younger and 103 older adults who completed nine cognitive tasks in 100 daily sessions, we show that the contributions of systematic day-to-day variability to overall observed variability are reliable but small. Thus, the impression of good versus bad days is largely due to performance fluctuations at faster timescales. Despite having lower average levels of performance, older adults showed more consistent levels of performance across days.

Poulenc Novelette No. 2 - a bit on the wild side

Poulenc's first two novelettes, the one in C major that I posted yesterday, and today's second novelette in B-flat minor, were composed in 1927 and 1928, and first performed by Poulenc at a Paris concert in June of 1928. The second novelette is in many ways similar to a scherzo, and very different from the sonorous and melodic first and third. All demonstrate multi-layered piano writing. Poulenc was mainly a self taught composer, and he was was one of the first openly gay composers, dedicating many of his pieces to his lovers. His most immediate influences were Chabrier, Debussy, Satie, and Stravinsky. Stravinsky helped get his early music published.