Tuesday, September 16, 2014

Norm enforcement is biased from its emergence.

Interesting work from Jordan et al. on the appearance of in-group bias in punishing selfish behaviors in insiders versus outsiders:

When enforcing norms for cooperative behavior, human adults sometimes exhibit in-group bias. For example, third-party observers punish selfish behaviors committed by out-group members more harshly than similar behaviors committed by in-group members. Although evidence suggests that children begin to systematically punish selfish behavior around the age of 6 y, the development of in-group bias in their punishment remains unknown. Do children start off enforcing fairness norms impartially, or is norm enforcement biased from its emergence? How does bias change over development? Here, we created novel social groups in the laboratory and gave 6- and 8-year-olds the opportunity to engage in costly third-party punishment of selfish sharing behavior. We found that by age 6, punishment was already biased: Selfish resource allocations received more punishment when they were proposed by out-group members and when they disadvantaged in-group members. We also found that although costly punishment increased between ages 6 and 8, bias in punishment partially decreased. Although 8-y-olds also punished selfish out-group members more harshly, they were equally likely to punish on behalf of disadvantaged in-group and out-group members, perhaps reflecting efforts to enforce norms impartially. Taken together, our results suggest that norm enforcement is biased from its emergence, but that this bias can be partially overcome through developmental change.

Monday, September 15, 2014

Early music training improves neural encoding of speech in children and arrests auditory decline in older adults.

Fascinating work from Kraus et al.:

Musicians are often reported to have enhanced neurophysiological functions, especially in the auditory system. Musical training is thought to improve nervous system function by focusing attention on meaningful acoustic cues, and these improvements in auditory processing cascade to language and cognitive skills. Correlational studies have reported musician enhancements in a variety of populations across the life span. In light of these reports, educators are considering the potential for co-curricular music programs to provide auditory-cognitive enrichment to children during critical developmental years. To date, however, no studies have evaluated biological changes following participation in existing, successful music education programs. We used a randomized control design to investigate whether community music participation induces a tangible change in auditory processing. The community music training was a longstanding and successful program that provides free music instruction to children from underserved backgrounds who stand at high risk for learning and social problems. Children who completed 2 years of music training had a stronger neurophysiological distinction of stop consonants, a neural mechanism linked to reading and language skills. One year of training was insufficient to elicit changes in nervous system function; beyond 1 year, however, greater amounts of instrumental music training were associated with larger gains in neural processing. We therefore provide the first direct evidence that community music programs enhance the neural processing of speech in at-risk children, suggesting that active and repeated engagement with sound changes neural function.
This same group has also documented how older adults benefit from early music training:
Aging results in pervasive declines in nervous system function. In the auditory system, these declines include neural timing delays in response to fast-changing speech elements; this causes older adults to experience difficulty understanding speech, especially in challenging listening environments. These age-related declines are not inevitable, however: older adults with a lifetime of music training do not exhibit neural timing delays. Yet many people play an instrument for a few years without making a lifelong commitment. Here, we examined neural timing in a group of human older adults who had nominal amounts of music training early in life, but who had not played an instrument for decades. We found that a moderate amount (4–14 years) of music training early in life is associated with faster neural timing in response to speech later in life, long after training stopped (>40 years). We suggest that early music training sets the stage for subsequent interactions with sound. These experiences may interact over time to sustain sharpened neural processing in central auditory nuclei well into older age.

Friday, September 12, 2014

Study on relationship between genomics and well being receives a critical trashing.

I recently did a post passing on (as usual, uncritically) what looked like a neat correlation between genomics and human well-being. Brown et al. now issue a foot stomping refutation of that work:

Fredrickson et al. [Fredrickson BL, et al. (2013) Proc Natl Acad Sci USA 110(33):13684–13689] claimed to have observed significant differences in gene expression related to hedonic and eudaimonic dimensions of well-being. Having closely examined both their claims and their data, we draw substantially different conclusions. After identifying some important conceptual and methodological flaws in their argument, we report the results of a series of reanalyses of their dataset. We first applied a variety of exploratory and confirmatory factor analysis techniques to their self-reported well-being data. A number of plausible factor solutions emerged, but none of these corresponded to Fredrickson et al.’s claimed hedonic and eudaimonic dimensions. We next examined the regression analyses that purportedly yielded distinct differential profiles of gene expression associated with the two well-being dimensions. Using the best-fitting two-factor solution that we identified, we obtained effects almost twice as large as those found by Fredrickson et al. using their questionable hedonic and eudaimonic factors. Next, we conducted regression analyses for all possible two-factor solutions of the psychometric data; we found that 69.2% of these gave statistically significant results for both factors, whereas only 0.25% would be expected to do so if the regression process was really able to identify independent differential gene expression effects. Finally, we replaced Fredrickson et al.’s psychometric data with random numbers and continued to find very large numbers of apparently statistically significant effects. We conclude that Fredrickson et al.’s widely publicized claims about the effects of different dimensions of well-being on health-related gene expression are merely artifacts of dubious analyses and erroneous methodology.

Thursday, September 11, 2014

A new compound that ameliorates cognitive dysfunction.

Alzheimer's disease is thought ultimately to be caused by the accumulation of the excess proteins found in plaques and tangles in the brain, but the prior defect that leads to this accumulation is not known. Here is a story about how searching for a drug for that defect led to the serendipitous finding of an impurity that turned out to be very useful...From Robinson's review of Xu et al.:

One implicated pathway involves striatal-enriched protein tyrosine phosphatase, or STEP, a neuron-specific enzyme that, among other jobs, regulates the trafficking of synaptic glutamate receptors and the activity of a group of widely active kinases. STEP is overactive in AD, in part because it isn't degraded fast enough, and its overactivity disrupts the post-synaptic events that underlie learning and memory. In animal models of AD, knocking out STEP improves cognition. Thus, STEP inhibition is a potential target for treatment of AD. In this issue of PLOS Biology, Jian Xu, Paul Lombroso, and colleagues report their discovery of a new class of STEP inhibitor—a discovery that involved a small but significant bit of serendipity—and demonstrate its potential in an AD animal model.
The authors began by conducting a high-throughput screen of 150,000 compounds, testing the ability of each to inhibit STEP's phosphatase activity. As is usual in such screens, a number of good candidates emerged. These were winnowed down to eight, chosen for their high activity at low concentration and favorable properties, such as likely ability to cross the blood-brain barrier and absence of known toxic moieties, all important for developing a centrally active drug. Following standard practice, next, they synthesized the molecules from scratch, and here got a surprise—the compounds displayed little STEP inhibitory activity. Some chemical detective work revealed the true inhibitor was elemental sulfur, S8, present as an impurity in the commercially obtained samples used in the screening. This ring compound doesn't make a good drug, so the authors investigated a structurally related compound, benzopentathiepin, containing a ring of six carbons fused to a ring of five sulfurs. A derivative, TC-2153, was known to have low toxicity and was likely to cross the blood-brain barrier, and, they found, was a potent inhibitor of STEP.

To test whether TC-2153 could reverse some of the cognitive effects of STEP overactivity, the authors turned to the “triple transgenic” mouse model, with mutations in three genes known to cause AD: presenilin 1, amyloid precursor protein, and tau. Compared to vehicle, intraperitoneal injection of TC-2153 improved spatial working memory, novel object recognition, and reference memory, all standard tests of cognitive function in AD models. The treatment had no effect on either a-beta, found in amyloid plaques outside of cortical neurons, or phospho-tau, found in neurofibrillary tangles inside them, indicating that the beneficial effect of TC-2153 was not due to alteration of events upstream of STEP overactivity.

Wednesday, September 10, 2014

Upstairs/Downstairs in our Brain – What’s running our show?

Although I mentioned this in Tuesday's post, I wanted to more explicitly point MindBlog readers to this web version of a talk I gave at the Sept. 9, 2014, session of the University of Wisconsin-Madison Chaos and Complexity Seminar Series. The link is also now in the left column of this page under "MindBlog Web Lectures." Here is a description of the talk:

This talk starts with a brief brain 101 elementary anatomy review, and then offers a  cherry picking review of recent trends in brain systems research that correlate what is going on in our brains with our behaviors. We want to know what normally makes us tick, what distortions might underlie addictive, impulsive, aggressive, stressed, depressed, or anxious behaviors, and what therapies might counter these distortions.  I will focus on structure-activity-behavior correlations in three brain state distinctions that are currently being emphasized:  Upstairs/downstairs and attentional/default mode systems that are a spontaneous part of our normal behavioral repertoire, and the cognitive therapy or mediation systems whose training, development, and expression can alter them.

Tuesday, September 09, 2014

MindBlog's other half - a Sunday afternoon recital at Twin Valley

This past Sunday afternoon my partner Len and I hosted a musical/social event for 50 friends at our Twin Valley home in Middleton Wisconsin. Our good friend Roy Wesley used his iPhone to make a video of the music, and I pass on his clip of one of the pieces in the program I played, the Debussy Nocturne (1892).

The program also included three pieces from Grieg's Lyric Suites and, Poulenc Improvisations #7 and #13 and, Prokofiev Romeo and Juliette

Reboot, reset, your brain - take a break - a walk, or better, a vacation.

I've done a number of posts on the attentional and default modes of our brain (in fact, I'm doing on a talk on this topic today at the Physics Department's chaos and complexity seminar series at the Univ. of Wisconsin.) I wanted to point to a number of recent popular articles pointing out how important it is for us to be able to detach from our attentional mode constantly processing overwhelming input streams of email, media, work demands, etc. While this more focused attentional mode tends to get a better press than the mind-wandering default mode, it is the latter state in which novel, spontaneous, and creative connections are likely to be made. Levitin does a NYTimes essay that notes the real world relevance of his 2008 publication on switching between central executive and default-mode networks, and notes that we should beware of the 'false break' in which we in fact remain attentive to email and other customary inputs, thus blocking real disengagement and mind wandering. Anna North and Gretchen Reynolds each do articles reinforcing this idea and point to articles studying the boosts in creativity and productivity that can accompany just taking a long walk or break.

Monday, September 08, 2014

MDMA (Ecstasy) as an affiliative social drug

Wardle et al. probe an interesting bit of social neurochemistry:

3,4-Methylenedioxymethamphetamine (MDMA, ‘ecstasy’) is used recreationally to improve mood and sociability, and has generated clinical interest as a possible adjunct to psychotherapy. One way that MDMA may produce positive ‘prosocial’ effects is by changing responses to emotional stimuli, especially stimuli with social content. Here, we examined for the first time how MDMA affects subjective responses to positive, negative and neutral emotional pictures with and without social content. We hypothesized that MDMA would dose-dependently increase reactivity to positive emotional stimuli and dampen reactivity to negative stimuli, and that these effects would be most pronounced for pictures with people in them. The data were obtained from two studies using similar designs with healthy occasional MDMA users (total N = 101). During each session, participants received MDMA (0, 0.75 and 1.5 mg/kg oral), and then rated their positive and negative responses to standardized positive, negative and neutral pictures with and without social content. MDMA increased positive ratings of positive social pictures, but reduced positive ratings of non-social positive pictures. We speculate this ‘socially selective’ effect contributes to the prosocial effects of MDMA by increasing the comparative value of social contact and closeness with others. This effect may also contribute to its attractiveness to recreational users.
MDMA primarily triggers transporter-mediated release of serotonin, suggesting that serotonin is a good candidate for being a key regulator of the desire to affiliate and bond with others. It also increases levels of oxytocin in the blood, but recent work indicates that there is no correlation between the changes in oxytocin in the plasma and changes in social behavior.

Friday, September 05, 2014

Does one novelty lead to another?

Barbar Jazney summarizes interesting work by Tria et al.:

Life would be boring if things were always the same. Tria and colleagues explore whether novelties—discoveries of things new to us—are independent of each other or whether one novelty leads to another. They analyzed selected text, online music, Wikipedia, and a social tagging site and measured how the number of different elements grew with time. Although two of the data sets contained innovations (items new to everyone) and two contained novelties (items new to individual users), they all showed the same kinetics and probability distributions. Modeling analyses suggested that novelties are not independent of each other. As the authors state, each novelty “comes with a cloud of other potentially new ideas that are thematically adjacent to it and hence can be triggered by it.”
Here is the Tria et al. article abstract:
Novelties are a familiar part of daily life. They are also fundamental to the evolution of biological systems, human society, and technology. By opening new possibilities, one novelty can pave the way for others in a process that Kauffman has called “expanding the adjacent possible”. The dynamics of correlated novelties, however, have yet to be quantified empirically or modeled mathematically. Here we propose a simple mathematical model that mimics the process of exploring a physical, biological, or conceptual space that enlarges whenever a novelty occurs. The model, a generalization of Polya's urn, predicts statistical laws for the rate at which novelties happen (Heaps' law) and for the probability distribution on the space explored (Zipf's law), as well as signatures of the process by which one novelty sets the stage for another. We test these predictions on four data sets of human activity: the edit events of Wikipedia pages, the emergence of tags in annotation systems, the sequence of words in texts, and listening to new songs in online music catalogues. By quantifying the dynamics of correlated novelties, our results provide a starting point for a deeper understanding of the adjacent possible and its role in biological, cultural, and technological evolution.

Thursday, September 04, 2014

Genetic influence on our valuation of free choice

Cockburn et al. find an interesting correlation: A polymorphism in DARPP-32, a gene linked to dopaminergic striatal plasticity and individual differences in reinforcement learning, predicts how strongly people exhibit preference for options they have freely chosen over equally valued options they have not. Here is their abstract, along with a statement of highlights:


Participants exhibit a biased preference for freely chosen rewarding options
DARPP-32 genotype predicts choice bias as a function of expected value
Bias is mirrored by a model that amplifies positive free-choice learning signals
Choice bias is the byproduct of a mechanism that refines learning signal fidelity
Humans exhibit a preference for options they have freely chosen over equally valued options they have not; however, the neural mechanism that drives this bias and its functional significance have yet to be identified. Here, we propose a model in which choice biases arise due to amplified positive reward prediction errors associated with free choice. Using a novel variant of a probabilistic learning task, we show that choice biases are selective to options that are predominantly associated with positive outcomes. A polymorphism in DARPP-32, a gene linked to dopaminergic striatal plasticity and individual differences in reinforcement learning, was found to predict the effect of choice as a function of value. We propose that these choice biases are the behavioral byproduct of a credit assignment mechanism responsible for ensuring the effective delivery of dopaminergic reinforcement learning signals broadcast to the striatum.

Wednesday, September 03, 2014

Morality - how theists and non theists differ

Shariff et al offer an interesting review of the ways in which the moral concerns of theists and nontheists both overlap and are different, as a result of psychological differences in social investment, motivations for prosocial behavior, meta-ethics, and cognitive styles. Some clips:

Many aspects of religions – such as their emphasis on credibility-enhancing displays of commitment – serve to create an ideologically aligned and cohesive ingroup… this tighter social connection may also lead to more parochial moral attitudes – selectively favoring the ingroup and actively derogating the outgroup.
Religious groups exert strong pressure on group members to conform to the requirements and moral ideals of the community. Although the drive to appear virtuous to others is all but universal, it is especially pronounced among theists. An extensive meta-analysis found theists scoring consistently higher than nontheists on measures of socially desirable responding…A recent meta-analysis revealed that nontheists, by contrast, are generally unaffected by invocations of supernatural agents; compared with baseline, nontheists tend to be no more prosocial when primed with god concepts…Nontheists do, however, show increases in prosocial behavior when primed with concepts relating to secular institutions, such as courts and the police.
For believers, God is not just the ultimate arbiter of justice, but the author of morality itself. This meta-ethical belief provides theists with a unique foundation for thinking about moral issues, distinct from their nonreligious counterparts. Recent research suggests that theists are moral objectivists; that is, they tend to believe that when two people disagree about a moral issue, only one person can be correct…religious individuals appear to moralize a wider range of actions beyond those pertaining to harm and injustice, including disobedience of authority, disloyalty to one's ingroup, and sexual impurity… By contrast, nontheists are more inclined than theists to view morality as subjective or culturally relative. Critically, however, this difference is more pronounced with regard to moral issues that have little to do with harm or injustice (e.g., sexual conduct).
Although theists and nontheists disagree whether obedience to authority or sexual impurity are morally relevant concepts, there is much greater consensus about moral issues involving harm and injustice. For example, both religious and nonreligious individuals take a predominantly deontological stance toward torture and both groups find acts of unjust harm (e.g., killing an innocent for no good reason) to be objectively wrong. All world religions defend some version of the Golden Rule, a doctrine that reflects evolved inclinations toward fairness and reciprocity. Recent studies suggest that individuals, independent of religion, exhibit an impulse to behave cooperatively and that they manage to override this immediate prosocial impulse only on further reflection. This universal preference toward prosociality is apparent even in infancy. Thus, although theists and nontheists may be divided through differences in sociality, earthly and supernatural reputational concerns, and meta-ethics, the two groups are united in what could be considered ‘core’ intuitive preferences for justice and compassion. Although the two groups may sometimes disagree about which groups or individuals deserve justice or their compassion, these core moral intuitions form the best basis for mutual understanding and intergroup conciliation.

Tuesday, September 02, 2014

Intergenerational transmission of emotional trauma.

Interesting work from Debiec and Sullivan on how conditioned fear learning in a parent is transmitted to children:

Despite clinical evidence that specific fear is transmitted across generations, we have little understanding of mechanisms. Here, we model social transmission of mother-to-infant fear in rodents. We show that maternal fear responses to a conditioned fear odor are sufficient to induce robust fear learning throughout infancy, with robust retention. Assessment of mechanism showed that maternal fear expression increases pups’ stress hormone corticosterone and amygdala activation to induce this cue-specific fear learning. Suppressing pups’ amygdala or preventing pups from mounting a stress response blocked this fear learning. Specific fears may thus be transferred across generations through maternal emotional communication and infant’s associative learning mechanisms. Elucidating the mechanisms of this transmission may inform the development of novel therapeutic and preventive approaches.

Monday, September 01, 2014

How could language have evolved?

An eminent group of co-authors (Bolhuis, Tattersall, Chomsky, and Berwick) suggest that a simple core repeatable operation is the basis of all language. This open source article is a "must read" item for anyone interested in the structure and evolution of language, and I pass on just the abstract and a bit on the basic model:

The evolution of the faculty of language largely remains an enigma. In this essay, we ask why. Language's evolutionary analysis is complicated because it has no equivalent in any nonhuman species. There is also no consensus regarding the essential nature of the language “phenotype.” According to the “Strong Minimalist Thesis,” the key distinguishing feature of language (and what evolutionary theory must explain) is hierarchical syntactic structure. The faculty of language is likely to have emerged quite recently in evolutionary terms, some 70,000–100,000 years ago, and does not seem to have undergone modification since then, though individual languages do of course change over time, operating within this basic framework. The recent emergence of language and its stability are both consistent with the Strong Minimalist Thesis, which has at its core a single repeatable operation that takes exactly two syntactic elements a and b and assembles them to form the set {a, b}.
...it appears that human language syntax can be defined in an extremely simple way that makes conventional evolutionary explanations much simpler. In this view, human language syntax can be characterized via a single operation that takes exactly two (syntactic) elements a and b and puts them together to form the set {a, b}. We call this basic operation “merge”. The “Strong Minimalist Thesis” (SMT) holds that merge along with a general cognitive requirement for computationally minimal or efficient search suffices to account for much of human language syntax. The SMT also requires two mappings: one to an internal conceptual interface for thought and a second to a sensory-motor interface that externalizes language as speech, sign, or other modality. The basic operation itself is simple. Given merge, two items such as the and apples are assembled as the set {the, apples}. Crucially, merge can apply to the results of its own output so that a further application of merge to ate and {the, apples} yields the set {ate, {the, apples}}, in this way deriving the full range of characteristic hierarchical structure that distinguishes human language from all other known nonhuman cognitive systems.

Friday, August 29, 2014

The origins of morality.

Mark Johnson has generated some creative and seminal ideas in his books "The Body in the Mind: The Bodily Basis of Meaning, Imagination, and Reason" and, with George Lakoff "Metaphors We Live By." I pass on a few clips from Les Beldo's review of his most recent book, "Morality for Humans Ethical Understanding from the Perspective of Cognitive Science":

Over the past 25 years, a growing number of cognitive scientists have taken it as their mission to find an empirical basis within brain science for the distinctive character of moral judgments. Investigators such as Marc Hauser, Steven Pinker, and Jonathan Haidt have posited the existence of an innate, domain-specific moral faculty in humans, be it a “universal moral grammar,” a “moral instinct,” or an “intuitive ethics.”
In Morality for Humans, Mark Johnson introduces an approach he calls “moral naturalism.” It is committed to the idea that moral knowledge does not exist on some separate plane but rather in the everyday habits, practices, institutions, and “bio-regulation” of lived organisms. Johnson is skeptical, however, of claims about the existence of a moral module in the human brain. He notes that “there are simply far too many complexly interacting multifunctional systems … in our intuitive moral judgments for there to be anything remotely resembling a distinct moral faculty.” Although he never uses the term, Johnson argues that moral problem-solving relies entirely on cognitive processes like logic, empathy, or narration. He sees the idea of an innate moral faculty as just another attempt to prove the existence of immutable moral laws, not in divine will or in pure reason but in a strong normative reading of cognitive science and evolutionary biology.
Johnson locates the source of values in our social and biological needs, cultural representations, and personal experiences. Here, Johnson has no qualms about violating the so-called naturalistic fallacy, which suggests that normative statements about how things ought to be cannot be derived from factual statements about what is. He moves freely between descriptions of human needs and human tendencies, on the one hand, and the normative suggestion that we ought to fulfill those needs and support those tendencies. Dismissing the naturalistic fallacy is easy if one thinks of it as an esoteric philosophical concept. But the term refers to a real logical problem of which Johnson is in fact acutely aware: “the fact that we have come to value certain states of affairs,” he writes, “is no guarantee that we should value them in the way we do.” This has been a particular weakness of studies that would make normative claims based on findings in cognitive neuroscience. How can descriptions of how our brains work tell us anything about what we ought to do in particular situations? It is a problem Johnson never resolves.
Morality is typically distinguished from other domains of social judgment by its unconditionality. A moral judgment refers to something that is considered right or wrong in and of itself. Johnson rejects the idea that moral judgments are unconditional, saying instead that the “trumping force” of morality owes to the fact that “certain things tend to matter more for us because they are thought to be necessary for the well-being of ourselves and others.” Individual well-being and societal cohesion are practical ends, however, and concerns about achieving them are matters of prudent conduct and prudent governance. This, along with Johnson's repeated insistence that moral problem-solving is no different in kind from any other form of problem-solving, leads one to wonder why he bothers to retain the concept of “morality” at all. Johnson suggests that values exist only in relation to some predefined or agreed-upon set of goods, feelings, or human needs, but that still creates fertile ground for hypothetical imperatives that are binding upon anyone who accepts the most basic premises of society. Why is this not enough? Is the stigma of moral relativism so frightening? What's so bad about prudence?

Thursday, August 28, 2014

The stability of the authoritarian state.

Science Magazine publishes comment on a fascinating article by King et al. who essentially reverse-engineer censorship in China to show that criticisms of the state, its leaders, and their policies are published, whereas posts about real-world events with collective action potential are censored. Criticism on the web, which was thought to be censored, is used by Chinese leaders to determine which officials are not doing their job of mollifying the people and need to be replaced. Here is the structured abstract from the article:

Censorship has a long history in China, extending from the efforts of Emperor Qin to burn Confucian texts in the third century BCE to the control of traditional broadcast media under Communist Party rule. However, with the rise of the Internet and new media platforms, more than 1.3 billion people can now broadcast their individual views, making information far more diffuse and considerably harder to control. In response, the government has built a massive social media censorship organization, the result of which constitutes the largest selective suppression of human communication in the recorded history of any country. We show that this large system, designed to suppress information, paradoxically leaves large footprints and so reveals a great deal about itself and the intentions of the government.
Chinese censorship of individual social media posts occurs at two levels: (i) Many tens of thousands of censors, working inside Chinese social media firms and government at several levels, read individual social media posts, and decide which ones to take down. (ii) They also read social media submissions that are prevented from being posted by automated keyword filters, and decide which ones to publish.
To study the first level, we devised an observational study to download published Chinese social media posts before the government could censor them, and to revisit each from a worldwide network of computers to see which was censored. To study the second level, we conducted the first largescale experimental study of censorship by creating accounts on numerous social media sites throughout China, submitting texts with different randomly assigned content to each, and detecting from a worldwide network of computers which ones were censored.
To find out the details of how the system works, we supplemented the typical current approach (conducting uncertain and potentially unsafe confidential interviews with insiders) with a participant observation study, in which we set up our own social media site in China. While also attempting not to alter the system we were studying, we purchased a URL, rented server space, contracted with Chinese firms to acquire the same software as used by existing social media sites, and—with direct access to their software, documentation, and even customer service help desk support—reverseengineered how it all works.
Criticisms of the state, its leaders, and their policies are routinely published, whereas posts with collective action potential are much more likely to be censored—regardless of whether they are for or against the state (two concepts not previously distinguished in the literature). Chinese people can write the most vitriolic blog posts about even the top Chinese leaders without fear of censorship, but if they write in support of or opposition to an ongoing protest—or even about a rally in favor of a popular policy or leader—they will be censored.
We clarify the internal mechanisms of the Chinese censorship apparatus and show how changes in censorship behavior reveal government intent by presaging their action on the ground. That is, it appears that criticism on the web, which was thought to be censored, is used by Chinese leaders to determine which officials are not doing their job of mollifying the people and need to be replaced.
Censorship in China is used to muzzle those outside government who attempt to spur the creation of crowds for any reason—in opposition to, in support of, or unrelated to the government. The government allows the Chinese people to say whatever they like about the state, its leaders, or their policies, because talk about any subject unconnected to collective action is not censored. The value that Chinese leaders find in allowing and then measuring criticism by hundreds of millions of Chinese people creates actionable information for them and, as a result, also for academic scholars and public policy analysts.

Wednesday, August 27, 2014

Early life anxiety in monkeys and humans correlates with connectivity between prefrontal cortex and amygdala.

A group of collaborators, mainly at the University of Wisconsin, including Ned Kalin and Richard Davidson, provide new information about the evolutionarily conserved brain network underlying extreme early-life anxiety:

Some individuals are endowed with a biology that renders them more reactive to novelty and potential threat. When extreme, this anxious temperament (AT) confers elevated risk for the development of anxiety, depression and substance abuse. These disorders are highly prevalent, debilitating and can be challenging to treat. The high-risk AT phenotype is expressed similarly in children and young monkeys and mechanistic work demonstrates that the central (Ce) nucleus of the amygdala is an important substrate. Although it is widely believed that the flow of information across the structural network connecting the Ce nucleus to other brain regions underlies primates’ capacity for flexibly regulating anxiety, the functional architecture of this network has remained poorly understood. Here we used functional magnetic resonance imaging (fMRI) in anesthetized young monkeys and quietly resting children with anxiety disorders to identify an evolutionarily conserved pattern of functional connectivity relevant to early-life anxiety. Across primate species and levels of awareness, reduced functional connectivity between the dorsolateral prefrontal cortex, a region thought to play a central role in the control of cognition and emotion, and the Ce nucleus was associated with increased anxiety assessed outside the scanner. Importantly, high-resolution 18-fluorodeoxyglucose positron emission tomography imaging provided evidence that elevated Ce nucleus metabolism statistically mediates the association between prefrontal-amygdalar connectivity and elevated anxiety. These results provide new clues about the brain network underlying extreme early-life anxiety and set the stage for mechanistic work aimed at developing improved interventions for pediatric anxiety.

Homologous dorsolateral prefrontal cortex (dlPFC) subdivisions show decreased intrinsic connectivity with the central (Ce) nucleus in anxious children and monkeys. (a) Children with anxiety disorders at rest. Bottom-left panel shows the Ce nucleus seed (cyan in red ring). Upper-left panel depicts a coronal slice through the human dlPFC cluster (dark orange; corrected for the combined volume of the mPFC and right dlPFC; n.s. when corrected for the volume of the whole brain). The intermediate frontal sulcus (IFS) is shown in dark red. Upper-right panel shows the IFS with the location of the coronal slice indicated by the blue vertical line. Bottom-right panel shows the location of the dlPFC cluster relative to the architectonic subdivisions of the human dlPFC. (b) Young monkeys with high levels of anxious temperament (AT) under anesthesia. Conventions are similar to a; dark red indicates the location of the sulcus principalis. The bottom-right panels of this figure were adapted with permission from Badre and D'Esposito.74 L, left hemisphere; R, right hemisphere.

Tuesday, August 26, 2014

More on better living through zapping your brain.

Anna Altman has done an entertaining piece on transcranial direct-current stimulation, or tDCS, which I have mentioned in numerous previous mindblog posts (enter tDCS in the mindblog search box). You can make your own tDCS machine from parts obtained at Radio Shack for ~ $20 or buy one off the web for $90. Various reports have shown enhanced alertness and learning, and palliative medical effect on chronic pain, stroke rehabilitation, and depressive disorders. Researchers go to lengths to warm of the potential downside effect of DIY (do it yourself) public experimentation. And indeed, so what if tDCS gives a bit of a boost?..

“Is brain boosting a fair addition to the cognitive enhancement arms race? Will it create a Morlock/Eloi-like social divide where the rich can afford to be smarter and leave everyone else behind? Will Tiger Moms force their lazy kids to strap on a zappity helmet during piano practice?” Or, she asks, “Could school-age girls use the zappy cap while studying math to drown out the voices that tell them they can’t do math because they’re girls?”

Monday, August 25, 2014

Origins of good and evil in human babies.

Felix Warneken does a review in TICS (Trends in Cognitive Sciences) of Paul Bloom new book "Just Babies: The Origins of Good and Evil," which argues that humans, already in the first year of life, have a basic moral sense that is shaped by innate evolved processes.

Bloom...reviews studies in which babies can choose to touch one of two geometrically shaped agents with googly eyes – and they prefer to touch one who helps a struggling fellow up a hill rather than one who pushes that fellow down. This indicates that babies like helping and despise harming others, even if they are only a third party who observes how other people treat each other. Beyond their judgments of the actions of others, young children also display helpful tendencies in their own behavior. Bloom reviews the extensive work on toddlers as young as 18 months of age who display a tendency to comfort others who are in distress, and spontaneously help clumsy people by picking up dropped objects and holding doors open. Last but not least, preschool children seem to have a sense of fairness when faced with the task of divvying up desirable resources, with equality already serving as a guiding principle.
...although our basic, parochially bound moral sentiments come naturally to us without much effort, applying these principles to strangers takes some mental effort. It requires that we employ perspective-taking in our interactions with others...Expanding our moral circle to include strangers thus depends on socialization and abilities that develop only in late childhood...our evolutionarily evolved morality is prepared for kin and friends, but not for strangers. This can be seen in young children's ingroup biases and toddlers’ stranger anxiety.
...human children depend more on interactions beyond the immediate family than do our closest evolutionary relatives... Infants thus have to tolerate being handed around and interact with many unfamiliar people from early on. We might therefore expect infants to be open-minded and vigilant at the same time, creating their social circles in a more sophisticated manner than ducklings who follow either white feathers or men with white beards, whichever they see first. And it seems as if they do so, not in a naïve fashion, but in a sophisticated way that balances risk and opportunity.

Friday, August 22, 2014

OhMyGawd...now MRI measurement are going to tell us how happy we are??

Dolan and collaborators come up with yet another clever use of MRI measurements. (If you enter "Dolan" in the mindblog search box, you will find numerous posts on his work.) The article appears to be open-source, which means I'm not going to pass on some of the eye-catching graphics (showing predictive activity in the striatum and right anterior insula) that you should be able to check out, along with the details of the experiment that recruited over 18,000 participants to play a smartphone gambling game and report their subjective happiness when queried.

A common question in the social science of well-being asks, “How happy do you feel on a scale of 0 to 10?” Responses are often related to life circumstances, including wealth. By asking people about their feelings as they go about their lives, ongoing happiness and life events have been linked, but the neural mechanisms underlying this relationship are unknown. To investigate it, we presented subjects with a decision-making task involving monetary gains and losses and repeatedly asked them to report their momentary happiness. We built a computational model in which happiness reports were construed as an emotional reactivity to recent rewards and expectations. Using functional MRI, we demonstrated that neural signals during task events account for changes in happiness.

Thursday, August 21, 2014

The source of consciousness.

Paller and Suzuki do a compact review on efforts to define the source of consciousness, arguing against the mysterian position that consciousness is beyond the scope of human understanding. They suggest that this position is like many other flaws in our common intuitions about consciousness. One of these is that if you direct your attention to something you must be aware of it. Not so, as this motion-induced blindness example demonstrates when you focus your attention on the central dot, with three surrounding yellow dots:

(to convince yourself the disappearing yellow dots are in fact always there enlarge the graphic to full screen and simply look at the wall or view beyond your tablet or monitor, perhaps scanning it back and forth, while letting the yellow dots remain in your peripheral vision.)

If paying attention doesn't guarantee awareness (as is the case in blindsight - in which objects can be discriminated without awareness of seeing them), what is the crucial ingredient? Current work suggests that exchange of information between specific cortical areas seems to be essential.

A clip:

The awareness we each have of our own body and our place in the world seems to be distinctly natural and fundamental. Yet the conscious experience of having a body can be bizarrely disrupted in patients with right parietal damage, who sometimes deny ownership of an entire arm. The rubber-hand illusion is another striking phenomenon, whereby seeing someone rubbing a fake hand while feeling the simultaneous tactile sensation on your own hand momentarily makes you feel that the fake hand is yours. In an even more extreme way, altered neural activity can produce an out-of-body experience.
These unusual perceptual experiences are no less ‘real’ than the sensation of a self inside a body. This standard way we each think of our self is a manufactured sensation, learned on the basis of sensory relationships across modalities. Awareness of a self inhabiting a body is not as obligatory as it seems: it is likely to have evolved for a behavioral advantage.
Why does the brain construct the sensation of a self inside a body? One answer appeals to the idea that you fare better in a social environment when you can attend to your own needs and predict what will happen next, including what other people are going to do. To make this work, specific brain mechanisms evolved to construct models of the attention and intentions of others and to localize them in the corresponding people's heads. The social neuroscience theory of consciousness [see my post on Graziano's ideas] postulates that these same brain mechanisms were adapted to construct a model of one's own attention and intentions, localized in one's own head and perceived as consciousness. If so, a primary function of consciousness is to allow us to predict our own behavior.
Another fragment of text:
...the neural processes that generate the subjective timing of a conscious decision that is seemingly instantaneous may be separate from the more protracted, unconscious processes that generate the content of the decision. The feeling of freely deciding at the precise time of our choosing may be a widespread illusion, albeit a beneficial one that promotes moral behavior and helps us to flourish as social beings.
When we recognize the shortcomings of common assumptions about consciousness, we are in a better position to develop an integrative understanding of the origin, evolution, development, and subjectivity of consciousness. Instead of emphasizing a single paradigm for examining awareness, we can be enriched by enlisting a variety of approaches, combining functional, biological, social, and computational perspectives.