Monday, August 27, 2018

On the reception and detection of pseudo-profound bullshit

I want to thank MindBlog reader Mike Walterman, who sent me an email pointing me to this article (which won an Ig Nobel Prize) and commented on his experience with "Flow Genome Project" which I reviewed in a Nov. 17, 2017 post titled "Modern flimflam men? - The Flow Genome Project". In commenting on this post, Mike described his experience of signing on for some classes with FGP:
I read your commentary on the Flow Genome Project (FGP) with great interest. Your suspicions about this "effort" are spot on, and I wish that I had your insight before taking two of these classes from the FGP. By the way, Steven Kotler is an alum of UW-Madison!!
The first class (Flow Fundamentals) was a great community of people, and I learned much from them, and nothing from the FGP personnel. The second class (Flow Performance) was pseudo-profound BS (PPBS.) There is a great paper that won an Ig Nobel Prize titled "On the reception and detection of pseudo-profound bullshit." ... The paper perfectly described every aspect of this class!! The instructor - Jamie Wheal - is more interested in impressing people with PPBS than realaying any useful information. Also, each class is prefaced with the promise that "All the secrets of Stealing Fire will be revealed in this next class." I stopped when this promise was not delivered in Flow Performance; but, was promised for private coaching (at an extremely high price).
Here is the abstract from the Pennycook et al. article on pseudo-profound bullshit:
Although bullshit is common in everyday life and has attracted attention from philosophers, its reception (critical or ingenuous) has not, to our knowledge, been subject to empirical investigation. Here we focus on pseudo-profound bullshit, which consists of seemingly impressive assertions that are presented as true and meaningful but are actually vacuous. We presented participants with bullshit statements consisting of buzzwords randomly organized into statements with syntactic structure but no discernible meaning (e.g., “Wholeness quiets infinite phenomena”). Across multiple studies, the propensity to judge bullshit statements as profound was associated with a variety of conceptually relevant variables (e.g., intuitive cognitive style, supernatural belief). Parallel associations were less evident among profundity judgments for more conventionally profound (e.g., “A wet person does not fear the rain”) or mundane (e.g., “Newborn babies require constant attention”) statements. These results support the idea that some people are more receptive to this type of bullshit and that detecting it is not merely a matter of indiscriminate skepticism but rather a discernment of deceptive vagueness in otherwise impressive sounding claims. Our results also suggest that a bias toward accepting statements as true may be an important component of pseudo-profound bullshit receptivity.

Friday, August 24, 2018

The architecture of pride is a cultural universal.

Sznycer et al. provide evidence that the pride system of WEIRD (western-ized, educated, industrialized, rich, and democratic) societies is found in 10 small-scale societies scattered across Central and South America, Africa, and Asia:

Significance
It has been proposed that one key function of pride is to guide behavior in ways that would increase others’ valuation of the individual. To incline choice, the pride system must compute for a potential action an anticipated pride intensity that tracks the magnitude of the approval or deference that the action would generate among local audiences. Data from industrial mass societies support this expectation. However, it is presently not known whether those data reflect cultural evolutionary processes or a panhuman adaptation. Experiments conducted in 10 traditional small-scale societies with widely varying cultures and subsistence modes replicate the pattern observed in mass societies. This suggests that pride is a universal system that is part of our species’ cooperative biology.
Abstract
Becoming valuable to fellow group members so that one would attract assistance in times of need is a major adaptive problem. To solve it, the individual needs a predictive map of the degree to which others value different acts so that, in choosing how to act, the payoff arising from others’ valuation of a potential action (e.g., showing bandmates that one is a skilled forager by pursuing a hard-to-acquire prey item) can be added to the direct payoff of the action (e.g., gaining the nutrients of the prey captured). The pride system seems to incorporate all of the elements necessary to solve this adaptive problem. Importantly, data from western(-ized), educated, industrialized, rich, and democratic (WEIRD) societies indicate close quantitative correspondences between pride and the valuations of audiences. Do those results generalize beyond industrial mass societies? To find out, we conducted an experiment among 567 participants in 10 small-scale societies scattered across Central and South America, Africa, and Asia: (i) Bosawás Reserve, Nicaragua; (ii) Cotopaxi, Ecuador; (iii) Drâa-Tafilalet, Morocco; (iv) Enugu, Nigeria; (v) Le Morne, Mauritius; (vi) La Gaulette, Mauritius; (vii) Tuva, Russia; (viii) Shaanxi and Henan, China; (ix) farming communities in Japan; and (x) fishing communities in Japan. Despite widely varying languages, cultures, and subsistence modes, pride in each community closely tracked the valuation of audiences locally (mean r = +0.66) and even across communities (mean r = +0.29). This suggests that the pride system not only develops the same functional architecture everywhere but also operates with a substantial degree of universality in its content.

Thursday, August 23, 2018

Our divided brains

I just came across an engaging video made by British psychiatrist Iain McGilchrist, and want to pass it on to MindBlog readers:


Wednesday, August 22, 2018

Brain tracking of musical beat is enhanced by low frequency sounds.

Lenc et al. find that that brain activity at the frequency of the perceived beat is selectively enhanced compared with other frequencies in the electroencephalogram (EEG) spectrum when rhythms are conveyed by bass sounds, explaining why across cultures bass instruments are used to induce people to dance to periodic pulse-like beats.
Music makes us move, and using bass instruments to build the rhythmic foundations of music is especially effective at inducing people to dance to periodic pulse-like beats. Here, we show that this culturally widespread practice may exploit a neurophysiological mechanism whereby low-frequency sounds shape the neural representations of rhythmic input by boosting selective locking to the beat. Cortical activity was captured using electroencephalography (EEG) while participants listened to a regular rhythm or to a relatively complex syncopated rhythm conveyed either by low tones (130 Hz) or high tones (1236.8 Hz). We found that cortical activity at the frequency of the perceived beat is selectively enhanced compared with other frequencies in the EEG spectrum when rhythms are conveyed by bass sounds. This effect is unlikely to arise from early cochlear processes, as revealed by auditory physiological modeling, and was particularly pronounced for the complex rhythm requiring endogenous generation of the beat. The effect is likewise not attributable to differences in perceived loudness between low and high tones, as a control experiment manipulating sound intensity alone did not yield similar results. Finally, the privileged role of bass sounds is contingent on allocation of attentional resources to the temporal properties of the stimulus, as revealed by a further control experiment examining the role of a behavioral task. Together, our results provide a neurobiological basis for the convention of using bass instruments to carry the rhythmic foundations of music and to drive people to move to the beat.

Tuesday, August 21, 2018

The false idols of wellness.

Jen Gunter does an engaging take-down of the wellness-industrial complex in a NYTimes piece. She suggests that the wellness industry is exploiting rather than filling the gaps left by normal medical practice.:
Wellness used to mean a blend of health and happiness...it has become a false antidote to the fear of modern life and death...The wellness industry takes medical terminology, such as “inflammation” or “free radicals,” and levigates it to the point of incomprehension. The resulting product is a D.I.Y. medicine for longevity that comes with a confidence that science can only aspire to achieve.
...take the trend of adding a pinch of activated charcoal to your food or drink...it’s sold as a supposed “detox.”..It has the same efficacy as a spell from the local witch...“Toxins,” as defined by the peddlers of these dubious cures, are the harmful effluvia of modern life that supposedly roam our bodies...for without these toxins there can be no search for purity — “clean” tampons, “clean” food, “clean” makeup. There are also sacred acts and rituals to follow...Medicine and religion have long been deeply intertwined, and it’s only relatively recently that they have separated. The wellness-industrial complex seeks to resurrect that connection. It’s like a medical throwback, as if the halcyon days of health were 5,000 years ago. Ancient cleansing rituals with a modern twist — supplements, useless products and scientifically unsupported tests.
The dietary supplements that are the backbone of wellness make up a $30 billion a year business despite studies showing they have no value for longevity...So what’s the harm of spending money on charcoal for nonexistent toxins or vitamins for expensive urine or grounding bedsheets to better connect you with the earth’s electrons?..Here’s what: the placebo effect or “trying something natural” can lead people with serious illnesses to postpone effective medical care.
Moving the kind of product that churns the wheels of the wellness-industrial complex requires a constant stream of fear and misinformation. Look closer at most wellness sites and at many of their physician partners, and you’ll find a plethora of medical conspiracy theories: Vaccines and autism. The dangers of water fluoridation. Bras and breast cancer. Cellphones and brain cancer. Heavy metal poisoning. AIDS as a construct of Big Pharma.
There are symptoms that I believe have been with us since the beginning of time, so common that they are likely part of the human experience: fatigue, bloat, low libido, episodic pain, loss of vigor. When medicine can only offer a therapy, not a cure, or when doctors give undesired answers — suggesting attention to sleep hygiene, for instance — it isn’t hard to see how the intoxicating confidence and theater of wellness could beckon.
I admit that doctors can learn something from wellness. It’s clear that some people are looking for healers, so we must find ways to serve that need that are medically ethical...We doctors can do more to provide factual information about hazardous substances, such as carcinogens and endocrine disrupting chemicals, in products and the environment from medically vetted sites with no products to sell, such as the National Cancer Institute and the Endocrine Society...Many people — women especially — have long been marginalized and dismissed by medicine, but the answer does not lie in predatory conspiracy theories, a faux religion or expensive magic.

Monday, August 20, 2018

Mesolimbic reward circuitry influences valuation of knowledge versus ignorance.

From Charpentier et al.:
The pursuit of knowledge is a basic feature of human nature. However, in domains ranging from health to finance people sometimes choose to remain ignorant. Here, we show that valence is central to the process by which the human brain evaluates the opportunity to gain information, explaining why knowledge may not always be preferred. We reveal that the mesolimbic reward circuitry selectively treats the opportunity to gain knowledge about future favorable outcomes, but not unfavorable outcomes, as if it has positive utility. This neural coding predicts participants’ tendency to choose knowledge about future desirable outcomes more often than undesirable ones, and to choose ignorance about future undesirable outcomes more often than desirable ones. Strikingly, participants are willing to pay both for knowledge and ignorance as a function of the expected valence of knowledge. The orbitofrontal cortex (OFC), however, responds to the opportunity to receive knowledge over ignorance regardless of the valence of the information. Connectivity between the OFC and mesolimbic circuitry could contribute to a general preference for knowledge that is also modulated by valence. Our findings characterize the importance of valence in information seeking and its underlying neural computation. This mechanism could lead to suboptimal behavior, such as when people reject medical screenings or monitor investments more during bull than bear markets.

Friday, August 17, 2018

Meditation quiets the ego? ….maybe just the opposite.

From Gebauer et al.. In their abstract "self-enhancement bias" refers to exaggerated self views or valuations.
Mind-body practices enjoy immense public and scientific interest. Yoga and meditation are highly popular. Purportedly, they foster well-being by curtailing self-enhancement bias. However, this “ego-quieting” effect contradicts an apparent psychological universal, the self-centrality principle. According to this principle, practicing any skill renders that skill self-central, and self-centrality breeds self-enhancement bias. We examined those opposing predictions in the first tests of mind-body practices’ self-enhancement effects. In Experiment 1, we followed 93 yoga students over 15 weeks, assessing self-centrality and self-enhancement bias after yoga practice (yoga condition, n = 246) and without practice (control condition, n = 231). In Experiment 2, we followed 162 meditators over 4 weeks (meditation condition: n = 246; control condition: n = 245). Self-enhancement bias was higher in the yoga (Experiment 1) and meditation (Experiment 2) conditions, and those effects were mediated by greater self-centrality. Additionally, greater self-enhancement bias mediated mind-body practices’ well-being benefits. Evidently, neither yoga nor meditation fully quiet the ego; to the contrary, they boost self-enhancement.

Thursday, August 16, 2018

The neuroscience of pessimism.

Ann Graybiel and collaborators offer a fascinating study showing that stimulation of the brain's caudate nucleus induces persistent and repetitive negative decision making. They devised a cost-benefit situation in which monkeys were offered a reward of juice paired with an unpleasant puff of air to the face. When the caudate nucleus was stimulated the animals began to avoid choosing the reward, when previously they would have put up with the unpleasant stimulus. This suggests that pessimistic decision-making can be tied to an overactive caudate nucleus. Work is now beginning with human patients suffering from anxiety and depression to find out whether abnormal activity in the caudate nucleus can be seen during negative decision making.

Highlights
Caudate nucleus stimulation induces persistent state change affecting value evaluation 
CN stimulation produces repetitive choices, whereas pACC stimulation does not 
CN beta oscillations parallel negative states influencing repetitive decisions 
Abnormal CN beta oscillations are correlated with persistency in OCD-like states
Summary P
ersistent thoughts inducing irrationally pessimistic and repetitive decisions are often symptoms of mood and anxiety disorders. Regional neural hyperactivities have been associated with these disorders, but it remains unclear whether there is a specific brain region causally involved in these persistent valuations. Here, we identified potential sources of such persistent states by microstimulating the striatum of macaques performing a task by which we could quantitatively estimate their subjective pessimistic states using their choices to accept or reject conflicting offers. We found that this microstimulation induced irrationally repetitive choices with negative evaluations. Local field potentials recorded in the same microstimulation sessions exhibited modulations of beta-band oscillatory activity that paralleled the persistent negative states influencing repetitive decisions. These findings demonstrate that local striatal zones can causally affect subjective states influencing persistent negative valuation and that abnormal beta-band oscillations can be associated with persistency in valuation accompanied by an anxiety-like state.

Wednesday, August 15, 2018

More evidence against the transferable benefits of online brain training on cognitive function

From Stojanoski et al.:
There is strong incentive to improve our cognitive abilities, and brain training has emerged as a promising approach for achieving this goal. While the idea that extensive ‘training’ on computerized tasks will improve general cognitive functioning is appealing, the evidence to support this remains contentious. This is, in part, because of poor criteria for selecting training tasks and outcome measures resulting in inconsistent definitions of what constitutes transferable improvement to cognition. The current study used a targeted training approach to investigate whether training on two different, but related, working memory tasks (across two experiments, with 72 participants) produced transferable benefits to similar (quantified based on cognitive and neural profiles) untrained test tasks. Despite significant improvement on both training tasks, participants did not improve on either test task. In fact, performance on the test tasks after training were nearly identical to a passive control group. These results indicate that, despite maximizing the likelihood of producing transferable benefits, brain training does not generalize, even to very similar tasks. Our study calls into question the benefit of cognitive training beyond practice effects, and provides a new framework for future investigations into the efficacy of brain training.

Tuesday, August 14, 2018

Rediscovering ancient greek music.

I want to point to a fascinating article by Armand D’Angour at Oxford University, on efforts to reconstruct what music sounded like in ancient Greece. The work is also described in this YouTube video:

Monday, August 13, 2018

Controlling drones with a body-machine interface.

On first glance this article creeped me out, because when control of drones at a distance is mentioned I think of the drones used to bomb ISIS or Al Quaeda cells controlled by operators in Tampa, FL. However, more benign or typical applications include deployments in environments where it is not desirable or possible to send a human operator, such as nuclear plants, scenes of natural hazards, or more generally in search and rescue missions. Also, the use of teleoperated systems can augment human dexterity and precision in fields such as minimally invasive surgery or microfabrication.

Miehlbradt et al. suggest an alternative to current control interfaces (frequently employing joysticks) that that require intensive practice. They have developed an intuitive gesture based interface for real and simulated drones. They recorded the upper-body kinematics and muscle activities during the generation of movements that would imitate the behavior of a flying drone. After identifying two main interaction strategies used by the participants, they assessed the capacity of potential users to actively steer the path of a virtual drone employing these two strategies. Eventually, they evaluated the transferability of the skills acquired during simulation training to the control of a real drone. Their abstract, and a video:
The accurate teleoperation of robotic devices requires simple, yet intuitive and reliable control interfaces. However, current human–machine interfaces (HMIs) often fail to fulfill these characteristics, leading to systems requiring an intensive practice to reach a sufficient operation expertise. Here, we present a systematic methodology to identify the spontaneous gesture-based interaction strategies of naive individuals with a distant device, and to exploit this information to develop a data-driven body–machine interface (BoMI) to efficiently control this device. We applied this approach to the specific case of drone steering and derived a simple control method relying on upper-body motion. The identified BoMI allowed participants with no prior experience to rapidly master the control of both simulated and real drones, outperforming joystick users, and comparing with the control ability reached by participants using the bird-like flight simulator Birdly.

Friday, August 10, 2018

No gender differences in early math cognition.

Kersey et al. have examined data from more than 500 children ranging in age from 6 months to 8 years across several tests of numerosity, counting, and elementary mathematics concepts. They found no differences in mathematical performance between boys and girls in any of the ages tested, suggesting that gender differences in STEM representation are unlikely to be due to intrinsic differences in cognitive ability.
Recent public discussions have suggested that the under-representation of women in science and mathematics careers can be traced back to intrinsic differences in aptitude. However, true gender differences are difficult to assess because sociocultural influences enter at an early point in childhood. If these claims of intrinsic differences are true, then gender differences in quantitative and mathematical abilities should emerge early in human development. We examined cross-sectional gender differences in mathematical cognition from over 500 children aged 6 months to 8 years by compiling data from five published studies with unpublished data from longitudinal records. We targeted three key milestones of numerical development: numerosity perception, culturally trained counting, and formal and informal elementary mathematics concepts. In addition to testing for statistical differences between boys’ and girls’ mean performance and variability, we also tested for statistical equivalence between boys’ and girls’ performance. Across all stages of numerical development, analyses consistently revealed that boys and girls do not differ in early quantitative and mathematical ability. These findings indicate that boys and girls are equally equipped to reason about mathematics during early childhood.

Thursday, August 09, 2018

A ecosystem of podcast bros who want to optimize your life.

I'm not a podcast or video kind of person, being too impatient to listen to or watch material that I can absorb more rapidly by reading about it. So, this piece by Molly Worthen describing a whole ecosystem of wellness gurus, a network of podcasters centered on Austin Texas and Southern California, was a revelation for me. (Note: this past November I did a post on an Austin based wellness project.) From her article:
...over the past few years the podcasters have become a significant cultural phenomenon, spiritual entrepreneurs who are filling the gap left as traditional religious organizations erode and modernity frays our face-to-face connections with communities and institutions...By my count, there are at least two dozen members of this podcast ecosystem...Several of these podcasters say they reach millions of listeners each month. In 2016, Joe Rogan put his figure “in the neighborhood of 30 million downloads per month”; his show is ranked second on the iTunes podcast chart, right behind Oprah.
In this secularized age of lonely seekers scrolling social media feeds, they have cultivated a spiritual community. They offer theologies and daily rituals of self-actualization, an appealing alternative to the rhetoric of victimhood and resentment that permeates both the right and the left...All this continues a long American tradition of self-help and creative, market-minded spirituality. The 19th century brimmed with gurus ready to guide you to other dimensions and prophets of the path from rags to riches.
Humans seem to be wired to seek salvation; even if polls suggest that more and more Americans reject traditional notions of God and skip church, it’s appealing to think that the latest lifestyle trend could be your path to existential bliss. The podcasters urge their listeners to experiment with fitness routines, diets, non-Western medicine, meditation and other “biohacks” to think more clearly, sleep more soundly and achieve professional success — and to quit blaming other people or bad luck for their problems.
Underlying this taste for experimentation is a deeper interest in evolutionary biology and psychology: the genes that, some experts believe, leave us programmed for a brutal, tribal, even pre-human past despite the creature comforts of the present...Evolutionary psychology is the secular answer to the doctrine of original sin: a primordial explanation for the anxieties that haunt us even if we have a decent job and a functional family...This is the podcast bro ethos: Ditch your ideologically charged identity. Accept your evolutionary programming. Take responsibility for mastering it, and find a cosmic purpose...Many have a strong interest in spirituality, and see practices like Buddhist meditation or consuming hallucinogenic “plant medicine” as not just a way to improve daily performance, but a path to something deeper.
The common thread linking the podcasters’ interest in evolutionary psychology and their metaphysical dabbling is the quest to transcend the ego, and to overcome the idea that we are personally aggrieved by enemies wholly unlike ourselves. This means mistrusting ideology and identitarian politics...having a one-world tribe, a tribe of human beings, period, is really what’s going to heal us for our next stage of life as a species on this planet.
Is this a postmodern monastic order, passing on breakfast and shivering in the shower while pondering the next step in mastering the ego? These podcasters lead one of the largest quasi-spiritual self-help “denominations” in the United States. It is a far-flung virtual community that gives people solace, a regimen and a sense of like-mindedness at a time when churches and other old-fashioned institutions simultaneously seem to ask too much, yet also fail to provide many people with whatever they’re looking for. The podcasters’ rejection of culture-wars partisanship resonates at a time when many Americans have stopped participating in politics (every listener I spoke to avoids political media the way they avoid, well, non-kale smoothies).
Yet podcasts are not churches. They are not political parties. They don’t patch over the existential void so much as reveal how avidly we yearn to fill it...The podcasters may offer a lesson to politicians and activists: to build a following, find a way to provide the sense of affiliation, daily rhythm and ultimate purpose that humans crave. Slogans of victimhood and grievance may rile up the base. But most people yearn, instead, for a sense of belonging and a path to mastery — even if it starts with a cold shower.

Wednesday, August 08, 2018

Our weaponized social media

I pass on a few clips from a sobering NYTimes article by Kara Swisher, who quotes from a recent Facebook post:
We face determined, well-funded adversaries who will never give up and are constantly changing tactics. It’s an arms race and we need to constantly improve too.
Continuing,
Facebook, as well as Twitter and Google’s YouTube, have become the digital arms dealers of the modern age...by weaponizing pretty much everything that could be weaponized. They have mutated human communication, so that connecting people has too often become about pitting them against one another, and turbocharged that discord to an unprecedented and damaging volume...They have weaponized social media. They have weaponized the First Amendment. They have weaponized civic discourse. And they have weaponized, most of all, politics.
Swisher's concluding paragraphs:
“I mean, my emotion is feeling a deep sense of responsibility to try to fix the problem,” said Mr. Zuckerberg. “In running a company, if you want to be innovative and advance things forward, I think you have to be willing to get some things wrong. But I don’t think it is acceptable to get the same things wrong over and over again.”
It was a classic Silicon Valley engineer’s roll-up-your-sleeves answer, which leaves many cold when it comes to, say, the manipulation of democracy. Fending off bad actors like the Russians has been and will be increasingly expensive; it may even be impossible. But Facebook could have done much more than it did, and it certainly needs to do more than it’s doing.
Mr. Zuckerberg is now trying to fend off talk in Washington of regulating his company like the thing he once told me it was: a utility. He has also spent the last month meeting over dinners with a range of academic experts on free speech, propaganda and more to try to understand where to go from here.
Call it the education of Mark Zuckerberg and Silicon Valley, but on the world’s dime. How much that has — and will — cost is probably immeasurable.

Tuesday, August 07, 2018

How pupil mimicry promotes trust.

Prochazkova et al. show that pupil mimicry promotes trust through our theory of mind brain network:

Significance
Trusting others is central for cooperative endeavors to succeed. To decide whether to trust or not, people generally make eye contact. As pupils of interaction partners align, mimicking pupil size helps them to make well-informed trust decisions. How the brain integrates information from the partner and from their own bodily feedback to make such decisions was unknown because previous research investigated these processes separately. Herein, we take a multimethod approach and demonstrate that pupil mimicry is regulated by the theory-of-mind network, and informs decisions of trust by activating the precuneus. This evolutionary ancient neurophysiological mechanism that is active in human adults, infants, and chimpanzees promotes affiliation, bonding, and trust through mimicry.
Abstract
The human eye can provide powerful insights into the emotions and intentions of others; however, how pupillary changes influence observers’ behavior remains largely unknown. The present fMRI–pupillometry study revealed that when the pupils of interacting partners synchronously dilate, trust is promoted, which suggests that pupil mimicry affiliates people. Here we provide evidence that pupil mimicry modulates trust decisions through the activation of the theory-of-mind network (precuneus, temporo-parietal junction, superior temporal sulcus, and medial prefrontal cortex). This network was recruited during pupil-dilation mimicry compared with interactions without mimicry or compared with pupil-constriction mimicry. Furthermore, the level of theory-of-mind engagement was proportional to individual’s susceptibility to pupil-dilation mimicry. These data reveal a fundamental mechanism by which an individual’s pupils trigger neurophysiological responses within an observer: when interacting partners synchronously dilate their pupils, humans come to feel reflections of the inner states of others, which fosters trust formation.

Monday, August 06, 2018

Brain regions involved in compensating for lost body parts.

From Striem-Amit et al.:

Significance
What determines the role of brain regions and their plasticity when typical inputs or experience is not provided? To what extent can extreme compensatory use affect brain organization? We tested the reorganization of primary and association sensorimotor cortex hand-selective areas in people born without hands, who use their feet for everyday tasks. We found that their primary sensorimotor hand area is preferentially activated for nearby body parts that cannot serve as effectors. In contrast, foot-selective compensatory plasticity was found in the association cortex, in an area typically involved in manual tool use. This shows limitations of compensatory plasticity and experience in modifying brain organization of early topographical cortex, as compared with association cortices where function-based organization is the driving factor.
Abstract
What forces direct brain organization and its plasticity? When brain regions are deprived of their input, which regions reorganize based on compensation for the disability and experience, and which regions show topographically constrained plasticity? People born without hands activate their primary sensorimotor hand region while moving body parts used to compensate for this disability (e.g., their feet). This was taken to suggest a neural organization based on functions, such as performing manual-like dexterous actions, rather than on body parts, in primary sensorimotor cortex. We tested the selectivity for the compensatory body parts in the primary and association sensorimotor cortex of people born without hands (dysplasic individuals). Despite clear compensatory foot use, the primary sensorimotor hand area in the dysplasic subjects showed preference for adjacent body parts that are not compensatorily used as effectors. This suggests that function-based organization, proposed for congenital blindness and deafness, does not apply to the primary sensorimotor cortex deprivation in dysplasia. These findings stress the roles of neuroanatomical constraints like topographical proximity and connectivity in determining the functional development of primary cortex even in extreme, congenital deprivation. In contrast, increased and selective foot movement preference was found in dysplasics’ association cortex in the inferior parietal lobule. This suggests that the typical motor selectivity of this region for manual actions may correspond to high-level action representations that are effector-invariant. These findings reveal limitations to compensatory plasticity and experience in modifying brain organization of early topographical cortex compared with association cortices driven by function-based organization.

Friday, August 03, 2018

Residential isolation of disadvantaged groups is not mitigated by extensive urban mobility.

Wang et al. offer yet another approach to observing the intractability of racial segregation in large cities:

Significance
Living in disadvantaged neighborhoods is widely assumed to undermine life chances because residents are isolated from neighborhoods with greater resources. Yet, residential isolation may be mitigated by individuals spending much of their everyday lives outside their home neighborhoods, a possibility that has been difficult to assess on a large scale. Using new methods to analyze urban mobility in the 50 largest American cities, we find that residents of primarily black and Hispanic neighborhoods—whether poor or not—are far less exposed to either nonpoor or white middle-class neighborhoods than residents of primarily white neighborhoods. Although residents of disadvantaged neighborhoods regularly travel as far and to as many different neighborhoods as those from advantaged neighborhoods, their relative isolation and segregation persist.
Abstract
Influential research on the negative effects of living in a disadvantaged neighborhood assumes that its residents are socially isolated from nonpoor or “mainstream” neighborhoods, but the extent and nature of such isolation remain in question. We develop a test of neighborhood isolation that improves on static measures derived from commonly used census reports by leveraging fine-grained dynamic data on the everyday movement of residents in America’s 50 largest cities. We analyze 650 million geocoded Twitter messages to estimate the home locations and travel patterns of almost 400,000 residents over 18 mo. We find surprisingly high consistency across neighborhoods of different race and income characteristics in the average travel distance (radius) and number of neighborhoods traveled to (spread) in the metropolitan region; however, we uncover notable differences in the composition of the neighborhoods visited. Residents of primarily black and Hispanic neighborhoods—whether poor or not—are far less exposed to either nonpoor or white middle-class neighborhoods than residents of primarily white neighborhoods. These large racial differences are notable given recent declines in segregation and the increasing diversity of American cities. We also find that white poor neighborhoods are substantially isolated from nonpoor white neighborhoods. The results suggest that even though residents of disadvantaged neighborhoods travel far and wide, their relative isolation and segregation persist.

Thursday, August 02, 2018

Chimps can psych out humans

Interesting work from Eckert et al. shows that chimps can use mental state information revealed by experimenters' biases in selecting food items.
Great apes have been shown to be intuitive statisticians: they can use proportional information within a population to make intuitive probability judgments about randomly drawn samples [unpublished data]. Humans, from early infancy onward, functionally integrate intuitive statistics with other cognitive domains to judge the randomness of an event. To date, nothing is known about such cross-domain integration in any nonhuman animal, leaving uncertainty about the origins of human statistical abilities. We investigated whether chimpanzees take into account information about psychological states of experimenters (their biases and visual access) when drawing statistical inferences. We tested 21 sanctuary-living chimpanzees in a previously established paradigm that required subjects to infer which of two mixed populations of preferred and non-preferred food items was more likely to lead to a desired outcome for the subject. In a series of three experiments, we found that chimpanzees chose based on proportional information alone when they had no information about experimenters’ preferences and (to a lesser extent) when experimenters had biases for certain food types but drew blindly. By contrast, when biased experimenters had visual access, subjects ignored statistical information and instead chose based on experimenters’ biases. Lastly, chimpanzees intuitively used a violation of statistical likelihoods as indication for biased sampling. Our results suggest that chimpanzees have a random sampling assumption that can be overridden under the appropriate circumstances and that they are able to use mental state information to judge whether this is necessary. This provides further evidence for a shared statistical inference mechanism in apes and humans.

Wednesday, August 01, 2018

Enhanced brain activity associated with highly superior memory.

Santangelo et al. show that people with superior memory have enhanced connectivity of their prefrontal cortex with their hippocampus and temporoparietal junction:

Significance
Recent research has identified human subjects who have highly superior autobiographical memory (HSAM). Here, we investigated, using fMRI, the neural activation induced by retrieval of autobiographical memories (AMs) and semantic memories (SMs) in subjects with HSAM and control subjects. While their brains were being scanned, subjects had to retrieve AMs as well as SMs (e.g., examples of animals). The subjects with HSAM displayed a superior ability to retrieve details of AMs, supported by enhanced activation of several brain regions, including the medial prefrontal cortex and temporoparietal junction, as well as increased connectivity of the prefrontal cortex with the hippocampus, a region well known to be involved in memory representation. These findings suggest that activation of these systems may play a critical role in enabling HSAM.
Abstract
Brain systems underlying human memory function have been classically investigated studying patients with selective memory impairments. The discovery of rare individuals who have highly superior autobiographical memory (HSAM) provides, instead, an opportunity to investigate the brain systems underlying enhanced memory. Here, we carried out an fMRI investigation of a group of subjects identified as having HSAM. During fMRI scanning, eight subjects with HSAM and 21 control subjects were asked to retrieve autobiographical memories (AMs) as well as non-AMs (e.g., examples of animals). Subjects were instructed to signal the “access” to an AM by a key press and to continue “reliving” it immediately after. Compared with controls, individuals with HSAM provided a richer AM recollection and were faster in accessing AMs. The access to AMs was associated with enhanced prefrontal/hippocampal functional connectivity. AM access also induced increased activity in the left temporoparietal junction and enhanced functional coupling with sensory cortices in subjects with HSAM compared with controls. In contrast, subjects with HSAM did not differ from controls in functional activity during the reliving phase. These findings, based on fMRI assessment, provide evidence of interaction of brain systems engaged in memory retrieval and suggest that enhanced activity of these systems is selectively involved in enabling more efficient access to past experiences in HSAM.

Tuesday, July 31, 2018

Are things getting better or worse?

In a recent New Yorker article Joshua Rothman discusses debate over assessing the state of the world, with major emphasis on Pinker book "Enlightenment Now", which was the subject of a series of MindBlog posts March 1 - March 12 of this year. Things like "Progressophobia" on the part of intellectuals, people seeing the past through rose colored glasses, and media emphasizing momentary crises over long term trends lead most people to think that the world is getting worse rather than better, which, Pinker says, is "wrong wrong, flat-earth wrong."

Rothman's brief reviews of a number of other books debating progress and optimism versus pessimism about the future make his article well worth reading. I'll pass on the end of the article (note especially the last paragraph), which points to a book by Hans Rosling:
In “Factfulness: Ten Reasons We’re Wrong About the World—and Why Things Are Better Than You Think,” the Swedish global-health statistician Hans Rosling, who wrote the book with his son and daughter-in-law, tries to find such a picture. Most depictions of the world, Rosling thinks, are either too optimistic or too pessimistic; if they don’t succumb to despair, they seem to look too quickly away from suffering. Rosling adopts a mantra—“Bad and better”—to avoid these extremes. “Think of the world as a premature baby in an incubator,” he suggests:
The baby’s health status is extremely bad, and her breathing, heart rate, and other important signs are tracked constantly so that changes for better or worse can quickly be seen. After a week, she is getting a lot better. On all the main measures, she is improving, but she still has to stay in the incubator because her health is still critical. Does it make sense to say that the infant’s situation is improving? Yes. Absolutely. Does it make sense to say it is bad? Yes, absolutely. Does saying “things are improving” imply that everything is fine, and we should all relax and not worry? No, not at all. Is it helpful to have to choose between bad and improving? Definitely not. It’s both. It’s both bad and better. Better, and bad, at the same time. . . . That is how we must think about the current state of the world.
Rosling’s image captures many of the perplexities of our collective situation. We desperately want the baby to survive. We also know that survival doesn’t guarantee happiness. The baby is struggling, and suffering, and will continue to do so; as a result, we’re more likely to be happy for her than she is to be happy for herself. (Pinker, similarly, is happier for us than we are.) It’s possible, moreover, that she’ll be saved only temporarily. No one is ever truly out of the woods.
In the meantime, the baby’s survival depends on the act of diagnosis. Until her ailments are identified, they can’t be cured. Problems and progress are inextricable, and the history of improvement is also the history of problem-discovery. Diagnosis, of course, is an art in itself; it’s possible to misunderstand problems, or to overstate them, and, in doing so, to make them worse. But a world in which no one complained—in which we only celebrated how good we have it—would be a world that never improved. The spirit of progress is also the spirit of discontent.

Monday, July 30, 2018

Piano training enhances speech perception.

Fascinating work from an international collaboration of Desimone at M.I.T., Nan at Beijing Normal Univ., and others:

Significance
Musical training is beneficial to speech processing, but this transfer’s underlying brain mechanisms are unclear. Using pseudorandomized group assignments with 74 4- to 5-year-old Mandarin-speaking children, we showed that, relative to an active control group which underwent reading training and a no-contact control group, piano training uniquely enhanced cortical responses to pitch changes in music and speech (as lexical tones). These neural enhancements further generalized to early literacy skills: Compared with the controls, the piano-training group also improved behaviorally in auditory word discrimination, which was correlated with their enhanced neural sensitivities to musical pitch changes. Piano training thus improves children’s common sound processing, facilitating certain aspects of language development as much as, if not more than, reading instruction.
Abstract
Musical training confers advantages in speech-sound processing, which could play an important role in early childhood education. To understand the mechanisms of this effect, we used event-related potential and behavioral measures in a longitudinal design. Seventy-four Mandarin-speaking children aged 4–5 y old were pseudorandomly assigned to piano training, reading training, or a no-contact control group. Six months of piano training improved behavioral auditory word discrimination in general as well as word discrimination based on vowels compared with the controls. The reading group yielded similar trends. However, the piano group demonstrated unique advantages over the reading and control groups in consonant-based word discrimination and in enhanced positive mismatch responses (pMMRs) to lexical tone and musical pitch changes. The improved word discrimination based on consonants correlated with the enhancements in musical pitch pMMRs among the children in the piano group. In contrast, all three groups improved equally on general cognitive measures, including tests of IQ, working memory, and attention. The results suggest strengthened common sound processing across domains as an important mechanism underlying the benefits of musical training on language processing. In addition, although we failed to find far-transfer effects of musical training to general cognition, the near-transfer effects to speech perception establish the potential for musical training to help children improve their language skills. Piano training was not inferior to reading training on direct tests of language function, and it even seemed superior to reading training in enhancing consonant discrimination.

Friday, July 27, 2018

Mechanism of white matter changes induced by meditation?

Posner and collaborators, who previously have shown changes in brain white matter induced by meditation, suggest a possible mechanism, using a mouse model.
Meditation has been shown to modify brain connections. However, the cellular mechanisms by which this occurs are not known. We hypothesized that changes in white matter found following meditation may be due to increased rhythmicity observed in frontal areas in the cortex. The current study in mice tested this directly by rhythmically stimulating cells in the frontal midline. We found that such stimulation caused an increase in connectivity due to changes in the axons in the corpus callosum, which transmit impulses to and from the frontal midline. This work provides a plausible but not proven mechanism through which a mental activity such as meditation can improve brain connectivity.

Thursday, July 26, 2018

The neuroscience of mindfulness meditation

I completely missed this review article by Posner and colleagues when it appeared, and am grateful for Bäumli's mention of it in her recent brief essay, which gives this link for downloading it. It has a mind numbing amount of information on research into the brain correlates of meditative practice and competence, summary tables, references, graphics. In this post I'm passing passing on the summary of key points and one graphic:

Key points
It is proposed that the mechanism through which mindfulness meditation exerts its effects is a process of enhanced self-regulation, including attention control, emotion regulation and self-awareness.
Research on mindfulness meditation faces a number of important challenges in study design that limit the interpretation of existing studies.
A number of changes in brain structure have been related to mindfulness meditation.
Mindfulness practice enhances attention. The anterior cingulate cortex is the region associated with attention in which changes in activity and/or structure in response to mindfulness meditation are most consistently reported.
Mindfulness practice improves emotion regulation and reduces stress. Fronto-limbic networks involved in these processes show various patterns of engagement by mindfulness meditation.
Meditation practice has the potential to affect self-referential processing and improve present-moment awareness. The default mode networks — including the midline prefrontal cortex and posterior cingulate cortex, which support self-awareness — could be altered following mindfulness training.
Mindfulness meditation has potential for the treatment of clinical disorders and might facilitate the cultivation of a healthy mind and increased well-being.
Future research into mindfulness meditation should use randomized and actively controlled longitudinal studies with large sample sizes to validate previous findings.
The effects of mindfulness practice on neural structure and function need to be linked to behavioural performance, such as cognitive, affective and social functioning, in future research.
The complex mental state of mindfulness is likely to be supported by the large-scale brain networks; future work should take this into account rather than being restricted to activations in single brain areas.

Legend - Schematic view of some of the brain regions involved in attention control (the anterior cingulate cortex and the striatum), emotion regulation (multiple prefrontal regions, limbic regions and the striatum) and self-awareness (the insula, medial prefrontal cortex and posterior cingulate cortex and precuneus).

Wednesday, July 25, 2018

When persistence doesn't pay - the sunk cost bias.

Sweis et al. show that sensitivity to time invested in pursuit of a reward occurs similarly in mice, rats, and humans. All three display a resistance to giving up their pursuit of a reward in a foraging context, but only after they have made the decision to pursue the reward. They suggest that there are two independent valuation processes, one assessing whether to accept an offer and the other — the one that is susceptible to sunk costs — assessing whether to continue investing in the choice. Their abstract:
Sunk costs are irrecoverable investments that should not influence decisions, because decisions should be made on the basis of expected future consequences. Both human and nonhuman animals can show sensitivity to sunk costs, but reports from across species are inconsistent. In a temporal context, a sensitivity to sunk costs arises when an individual resists ending an activity, even if it seems unproductive, because of the time already invested. In two parallel foraging tasks that we designed, we found that mice, rats, and humans show similar sensitivities to sunk costs in their decision-making. Unexpectedly, sensitivity to time invested accrued only after an initial decision had been made. These findings suggest that sensitivity to temporal sunk costs lies in a vulnerability distinct from deliberation processes and that this distinction is present across species.

Tuesday, July 24, 2018

Declining mental health among disadvantaged Americans.

Cherlin summarizes work by Goldman et al. that demonstrates "a troubling portrait of declining psychological health among non-Hispanic whites in mid- and later-life between the mid-1990s and the early 2010s... Equally troubling is the concentration of these declines among individuals with lower SES (socioeconomic status...life satisfaction declined for people at the 10th, 25th, and 50th percentiles of SES, remained constant for people at the 75th percentile, and increased for people at the 90th percentile. To the list of widening inequalities in the United States, which center on economic inequality, we must now add inequality in psychological health.

The Goldman et al. Abstract:

Significance
In the past few years, references to the opioid epidemic, drug poisonings, and associated feelings of despair among Americans, primarily working-class whites, have flooded the media, and related patterns of mortality have been of increasing interest to social scientists. Yet, despite recurring references to distress or despair in journalistic accounts and academic studies, there has been little analysis of whether psychological health among American adults has worsened over the past two decades. Here, we use data from national samples of adults in the mid-1990s and early 2010s to demonstrate increasing distress and declining well-being that was concentrated among low-socioeconomic-status individuals but spanned the age range from young to older adults.
Abstract
Although there is little dispute about the impact of the US opioid epidemic on recent mortality, there is less consensus about whether trends reflect increasing despair among American adults. The issue is complicated by the absence of established scales or definitions of despair as well as a paucity of studies examining changes in psychological health, especially well-being, since the 1990s. We contribute evidence using two cross-sectional waves of the Midlife in the United States (MIDUS) study to assess changes in measures of psychological distress and well-being. These measures capture negative emotions such as sadness, hopelessness, and worthlessness, and positive emotions such as happiness, fulfillment, and life satisfaction. Most of the measures reveal increasing distress and decreasing well-being across the age span for those of low relative socioeconomic position, in contrast to little decline or modest improvement for persons of high relative position.

Monday, July 23, 2018

Therapy for NYTAD - read about citrus micro-jets!

What is NYTAD? My just made up acronym for “New York Times Anxiety Disorder” - what I have to resist during my daily glance through the endless list of NYT and WaPo articles on the awful human being who serves as our president. And then, unexpectedly, a point of light. A neat article about something else: the microjets of citrus oil you see when you squeeze the skin of an orange or lemon. It turns out that the layered construction of the citrus exocarp allows for the buildup of fluid pressure in citrus oil gland reservoirs and their subsequent explosive rupture . I'll pass on the abstract of the PNAS article to which it refers, which gives the interesting details, along with a video.

Significance
Here we show a unique, natural method for microscale jetting of fluid made possible by the tuning of material properties from which the jets emanate. The composite, layered construction of the citrus exocarp allows for the buildup of fluid pressure in citrus oil gland reservoirs and their subsequent explosive rupture. Citrus jetting has not been documented in literature, and its purpose is unknown. This method for microscale fluid dispersal requires no auxiliary equipment and may open avenues for new methods of medicine and chemical delivery. We show how jet kinematics are related to substrate properties and reservoir shape.
Abstract
The rupture of oil gland reservoirs housed near the outer surface of the citrus exocarp is a common experience to the discerning citrus consumer and bartenders the world over. These reservoirs often rupture outwardly in response to bending the peel, which compresses the soft material surrounding the reservoirs, the albedo, increasing fluid pressure in the reservoir. Ultimately, fluid pressure exceeds the failure strength of the outermost membrane, the flavedo. The ensuing high-velocity discharge of oil and exhaustive emptying of oil gland reservoirs creates a method for jetting small quantities of the aromatic oil. We compare this jetting behavior across five citrus hybrids through high-speed videography. The jetting oil undergoes an extreme acceleration to reach velocities in excess of 10 m/s. Through material characterization and finite element simulations, we rationalize the combination of tuned material properties and geometries enabling the internal reservoir pressures that produce explosive dispersal, finding the composite structure of the citrus peel is critical for microjet production.

Friday, July 20, 2018

Crows make mental templates.

Weintraub points to further studies from the University of Aukland School of Psychology on the extraordinary New Caledonian crows that have been shown to learn tool use. They also appear to use “mental template matching” - forming an image in their heads of tools they have seen used by others, and then copying them.

 

Thursday, July 19, 2018

Perceptual and judgement creep.

Fascinating work by Gilbert and colleagues:
Why do some social problems seem so intractable? In a series of experiments, we show that people often respond to decreases in the prevalence of a stimulus by expanding their concept of it. When blue dots became rare, participants began to see purple dots as blue; when threatening faces became rare, participants began to see neutral faces as threatening; and when unethical requests became rare, participants began to see innocuous requests as unethical. This “prevalence-induced concept change” occurred even when participants were forewarned about it and even when they were instructed and paid to resist it. Social problems may seem intractable in part because reductions in their prevalence lead people to see more of them.


Wednesday, July 18, 2018

Authentic lies.

Hahl et al. suggest how a blatantly lying demagogue (guess who?) can be perceived as authentic:
We develop and test a theory to address a puzzling pattern that has been discussed widely since the 2016 U.S. presidential election and reproduced here in a post-election survey: how can a constituency of voters find a candidate “authentically appealing” (i.e., view him positively as authentic) even though he is a “lying demagogue” (someone who deliberately tells lies and appeals to non-normative private prejudices)? Key to the theory are two points: (1) “common-knowledge” lies may be understood as flagrant violations of the norm of truth-telling; and (2) when a political system is suffering from a “crisis of legitimacy” with respect to at least one political constituency, members of that constituency will be motivated to see a flagrant violator of established norms as an authentic champion of its interests. Two online vignette experiments on a simulated college election support our theory. These results demonstrate that mere partisanship is insufficient to explain sharp differences in how lying demagoguery is perceived, and that several oft-discussed factors—information access, culture, language, and gender—are not necessary for explaining such differences. Rather, for the lying demagogue to have authentic appeal, it is sufficient that one side of a social divide regards the political system as flawed or illegitimate.

Tuesday, July 17, 2018

Social media and the emergence of violence during protests.

The social media, and especially Twitter, are now integral to modern political behavior, with events online both reflecting and influencing actions offline. Mooijman et al. have used geolocated Twitter data to argue that moralization of protests leads to violent protests and increased support for violence.
In recent years, protesters in the United States have clashed violently with police and counter-protesters on numerous occasions. Despite widespread media attention, little scientific research has been devoted to understanding this rise in the number of violent protests. We propose that this phenomenon can be understood as a function of an individual’s moralization of a cause and the degree to which they believe others in their social network moralize that cause. Using data from the 2015 Baltimore protests, we show that not only did the degree of moral rhetoric used on social media increase on days with violent protests but also that the hourly frequency of morally relevant tweets predicted the future counts of arrest during protests, suggesting an association between moralization and protest violence. To better understand the structure of this association, we ran a series of controlled behavioural experiments demonstrating that people are more likely to endorse a violent protest for a given issue when they moralize the issue; however, this effect is moderated by the degree to which people believe others share their values. We discuss how online social networks may contribute to inflations of protest violence.

Monday, July 16, 2018

What is consciousness, and could machines have it?

I want to point to a lucid article by Dehaene, Lau, and Koulder that gives the most clear review I have seen of our current state of knowledge on the nature of human consciousness, which we need to define if we wish to consider the question of machines being conscious like us.   Here is the abstract, followed by a few edited clips that attempt to communicate the core points (motivated readers can obtain the whole text by emailing me):
The controversial question of whether machines may ever be conscious must be based on a careful consideration of how consciousness arises in the only physical system that undoubtedly possesses it: the human brain. We suggest that the word “consciousness” conflates two different types of information-processing computations in the brain: the selection of information for global broadcasting, thus making it flexibly available for computation and report (C1, consciousness in the first sense), and the self-monitoring of those computations, leading to a subjective sense of certainty or error (C2, consciousness in the second sense). We argue that despite their recent successes, current machines are still mostly implementing computations that reflect unconscious processing (C0) in the human brain. We review the psychological and neural science of unconscious (C0) and conscious computations (C1 and C2) and outline how they may inspire novel machine architectures.
C1: Global availability
This corresponds to the transitive meaning of consciousness (as in “The driver is conscious of the light”)... We can recall it, act upon it, and speak about it. This sense is synonymous with “having the information in mind”; among the vast repertoire of thoughts that can become conscious at a given time, only that which is globally available constitutes the content of C1 consciousness.
C2: Self-monitoring
Another meaning of consciousness is reflexive. It refers to a self-referential relationship in which the cognitive system is able to monitor its own processing and obtain information about itself..This sense of consciousness corresponds to what is commonly called introspection, or what psychologists call “meta-cognition”—the ability to conceive and make use of internal representations of one’s own knowledge and abilities.
CO: Unconscious processing: Where most of our intelligence lies
...many computations involve neither C1 nor C2 and therefore are properly called “unconscious” ...Cognitive neuroscience confirms that complex computations such as face or speech recognition, chess-game evaluation, sentence parsing, and meaning extraction occur unconsciously in the human brain—under conditions that yield neither global reportability nor self-monitoring. The brain appears to operate, in part, as a juxtaposition of specialized processors or “modules” that operate nonconsciously and, we argue, correspond tightly to the operation of current feedforward deep-learning networks.
The phenomenon of priming illustrates the remarkable depth of unconscious processing...Subliminal digits, words, faces, or objects can be invariantly recognized and influence motor, semantic, and decision levels of processing. Neuroimaging methods reveal that the vast majority of brain areas can be activated nonconsciously...Subliminal priming generalizes across visual-auditory modalities...Even the semantic meaning of sensory input can be processed without awareness by the human brain.
...subliminal primes can influence prefrontal mechanisms of cognitive control involved in the selection of a task...Neural mechanisms of decision-making involve accumulating sensory evidence that affects the probability of the various choices until a threshold is attained. This accumulation of probabilistic knowledge continues to happen even with subliminal stimuli. Bayesian inference and evidence accumulation, which are cornerstone computations for AI, are basic unconscious mechanisms for humans.
Reinforcement learning algorithms, which capture how humans and animals shape their future actions on the basis of history of past rewards, have excelled in attaining supra-human AI performance in several applications, such as playing Go. Remarkably, in humans, such learning appears to proceed even when the cues, reward, or motivation signals are presented below the consciousness threshold.
What additional computations are required for conscious processing?

C1: Global availability of relevant information
The need for integration and coordination. Integrating all of the available evidence to converge toward a single decision is a computational requirement that, we contend, must be faced by any animal or autonomous AI system and corresponds to our first functional definition of consciousness: global availability (C1)...Such decision-making requires a sophisticated architecture for (i) efficiently pooling over all available sources of information, including multisensory and memory cues; (ii) considering the available options and selecting the best one on the basis of this large information pool; (iii) sticking to this choice over time; and (iv) coordinating all internal and external processes toward the achievement of that goal.
Consciousness as access to an internal global workspace. We hypothesize that...On top of a deep hierarchy of specialized modules, a “global neuronal workspace,” with limited capacity, evolved to select a piece of information, hold it over time, and share it across modules. We call “conscious” whichever representation, at a given time, wins the competition for access to this mental arena and gets selected for global sharing and decision-making.
Relation between consciousness and attention. William James described attention as “the taking possession by the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought”. This definition is close to what we mean by C1: the selection of a single piece of information for entry into the global workspace. There is, however, a clear-cut distinction between this final step, which corresponds to conscious access, and the previous stages of attentional selection, which can operate unconsciously...What we call attention is a hierarchical system of sieves that operate unconsciously. Such unconscious systems compute with probability distributions, but only a single sample, drawn from this probabilistic distribution, becomes conscious at a given time. We may become aware of several alternative interpretations, but only by sampling their unconscious distributions over time.
Evidence for all-or-none selection in a capacity-limited system. The primate brain comprises a conscious bottleneck and can only consciously access a single item at a time. For instance, rivaling pictures or ambiguous words are perceived in an all-or-none manner; at any given time, we subjectively perceive only a single interpretation out of many possible ones [even though the others continue to be processed unconsciously]...Brain imaging in humans and neuronal recordings in monkeys indicate that the conscious bottleneck is implemented by a network of neurons that is distributed through the cortex, but with a stronger emphasis on high-level associative areas. ... Single-cell recordings indicate that each specific conscious percept, such as a person’s face, is encoded by the all-or-none firing of a subset of neurons in high-level temporal and prefrontal cortices, whereas others remain silent...the stable, reproducible representation of high-quality information by a distributed activity pattern in higher cortical areas is a feature of conscious processing. Such transient “meta-stability” seems to be necessary for the nervous system to integrate information from a variety of modules and then broadcast it back to them, achieving flexible cross-module routing.
C1 consciousness in human and nonhuman animals. C1 consciousness is an elementary property that is present in human infants as well as in animals. Nonhuman primates exhibit similar visual illusions, attentional blink, and central capacity limits as human subjects.
C2: Self-monitoring
Whereas C1 consciousness reflects the capacity to access external information, consciousness in the second sense (C2) is characterized by the ability to reflexively represent oneself ("metacognition")
A probabilistic sense of confidence. Confidence can be assessed nonverbally, either retrospectively, by measuring whether humans persist in their initial choice, or prospectively, by allowing them to opt out from a task without even attempting it. Both measures have been used in nonhuman animals to show that they too possess metacognitive abilities. By contrast, most current neural networks lack them: Although they can learn, they generally lack meta-knowledge of the reliability and limits of what has been learned...Magnetic resonance imaging (MRI) studies in humans and physiological recordings in primates and even in rats have specifically linked such confidence processing to the prefrontal cortex. Inactivation of the prefrontal cortex can induce a specific deficit in second-order (metacognitive) judgements while sparing performance on the first-order task. Thus, circuits in the prefrontal cortex may have evolved to monitor the performance of other brain processes.
Error detection: Reflecting on one’s own mistakes ...just after responding, we sometimes realize that we made an error and change our mind. Error detection is reflected by two components of electroencephalography (EEG) activity: the error-relativity negativity (ERN) and the positivity upon error (Pe), which emerge in cingulate and medial prefrontal cortex just after a wrong response but before any feedback is received...A possibility compatible with the remarkable speed of error detection is that two parallel circuits, a low-level sensory-motor circuit and a higher-level intention circuit, operate on the same sensory data and signal an error whenever their conclusions diverge. Self-monitoring is such a basic ability that it is already present during infancy. The ERN, indicating error monitoring, is observed when 1-year-old infants make a wrong choice in a perceptual decision task.
Meta-memory The term “meta-memory” was coined to capture the fact that humans report feelings of knowing, confidence, and doubts on their memories. ...Meta-memory is associated with prefrontal structures whose pharmacological inactivation leads to a metacognitive impairment while sparing memory performance itself. Metamemory is crucial to human learning and education by allowing learners to develop strategies such as increasing the amount of study or adapting the time allocated to memory encoding and rehearsal.
Reality monitoring. In addition to monitoring the quality of sensory and memory representations, the human brain must also distinguish self-generated versus externally driven representations - we can perceive things, but we also conjure them from imagination or memory...Neuroimaging studies have linked this kind of reality monitoring to the anterior prefrontal cortex
Dissociations between C1 and C2
According to our analysis, C1 and C2 are largely orthogonal and complementary dimensions of what we call consciousness. On one side of this double dissociation, self-monitoring can exist for unreportable stimuli (C2 without C1). Automatic typing provides a good example: Subjects slow down after a typing mistake, even when they fail to consciously notice the error. Similarly, at the neural level, an ERN can occur for subjectively undetected errors. On the other side of this dissociation, consciously reportable contents sometimes fail to be accompanied with an adequate sense of confidence (C1 without C2). For instance, when we retrieve a memory, it pops into consciousness (C1) but sometimes without any accurate evaluation of its confidence (C2), leading to false memories.
Synergies between C1 and C2 consciousness
Because C1 and C2 are orthogonal, their joint possession may have synergistic benefits to organisms. In one direction, bringing probabilistic metacognitive information (C2) into the global workspace (C1) allows it to be held over time, integrated into explicit long-term reflection, and shared with others...In the converse direction, the possession of an explicit repertoire of one’s own abilities (C2) improves the efficiency with which C1 information is processed. During mental arithmetic, children can perform a C2-level evaluation of their available competences (for example, counting, adding, multiplying, or memory retrieval) and use this information to evaluate how to best face a given arithmetic problem.
Endowing machines with C1 and C2
[Note: I am not abstracting this section as I did the above descriptions of consciousness. It describes numerous approaches rising above the level of most present day machines to making machines able to perform C1 and C2 operations.]
Most present-day machine-learning systems are devoid of any self-monitoring; they compute (C0) without representing the extent and limits of their knowledge or the fact that others may have a different viewpoint than their own. There are a few exceptions: Bayesian networks or programs compute with probability distributions and therefore keep track of how likely they are to be correct. Even when the primary computation is performed by a classical CNN, and is therefore opaque to introspection, it is possible to train a second, hierarchically higher neural network to predict the first one’s performance.
Concluding remarks
Our stance is based on a simple hypothesis: What we call “consciousness” results from specific types of information-processing computations, physically realized by the hardware of the brain. It differs from other theories in being resolutely computational; we surmise that mere information-theoretic quantities do not suffice to define consciousness unless one also considers the nature and depth of the information being processed.
We contend that a machine endowed with C1 and C2 would behave as though it were conscious; for instance, it would know that it is seeing something, would express confidence in it, would report it to others, could suffer hallucinations when its monitoring mechanisms break down, and may even experience the same perceptual illusions as humans. Still, such a purely functional definition of consciousness may leave some readers unsatisfied. Are we “over-intellectualizing” consciousness, by assuming that some high-level cognitive functions are necessarily tied to consciousness? Are we leaving aside the experiential component (“what it is like” to be conscious)? Does subjective experience escape a computational definition?
Although those philosophical questions lie beyond the scope of the present paper, we close by noting that empirically, in humans the loss of C1 and C2 computations covaries with a loss of subjective experience. For example, in humans, damage to the primary visual cortex may lead to a neurological condition called “blindsight,” in which the patients report being blind in the affected visual field. Remarkably, those patients can localize visual stimuli in their blind field but cannot report them (C1), nor can they effectively assess their likelihood of success (C2)—they believe that they are merely “guessing.” In this example, at least, subjective experience appears to cohere with possession of C1 and C2. Although centuries of philosophical dualism have led us to consider consciousness as unreducible to physical interactions, the empirical evidence is compatible with the possibility that consciousness arises from nothing more than specific computations.



Friday, July 13, 2018

Playing with proteins in virtual reality.

Much of my mental effort while I was doing laboratory research on the mechanisms of visual transduction (changing light into a nerve signal in our retinal rod and cone photoreceptor cells) was devoted to trying to visualize how proteins might interact with each other. I spent many hours using molecular model kits of color-coded plastic atoms one could plug together with flexible joints, like the Tinkertoys of my childhood. If I had only had the system now described by O'Connor et al! Have a look at the video below showing manipulating molecular dynamics in a VR environment,  and here is their abstract:
We describe a framework for interactive molecular dynamics in a multiuser virtual reality (VR) environment, combining rigorous cloud-mounted atomistic physics simulations with commodity VR hardware, which we have made accessible to readers (see isci.itch.io/nsb-imd). It allows users to visualize and sample, with atomic-level precision, the structures and dynamics of complex molecular structures “on the fly” and to interact with other users in the same virtual environment. A series of controlled studies, in which participants were tasked with a range of molecular manipulation goals (threading methane through a nanotube, changing helical screw sense, and tying a protein knot), quantitatively demonstrate that users within the interactive VR environment can complete sophisticated molecular modeling tasks more quickly than they can using conventional interfaces, especially for molecular pathways and structural transitions whose conformational choreographies are intrinsically three-dimensional. This framework should accelerate progress in nanoscale molecular engineering areas including conformational mapping, drug development, synthetic biology, and catalyst design. More broadly, our findings highlight the potential of VR in scientific domains where three-dimensional dynamics matter, spanning research and education.

Sampling molecular conformational dynamics in virtual reality from david glowacki on Vimeo.




Thursday, July 12, 2018

Increasing despair among poor Americans.

A survey by Goldman et al. of more than 4,600 American adults conducted in 1995-1996 and in 2011-2014 suggests that among individuals of low socioeconomic status, negative affect increased significantly between the two survey waves, and life satisfaction and psychological well-being decreased:

Significance
In the past few years, references to the opioid epidemic, drug poisonings, and associated feelings of despair among Americans, primarily working-class whites, have flooded the media, and related patterns of mortality have been of increasing interest to social scientists. Yet, despite recurring references to distress or despair in journalistic accounts and academic studies, there has been little analysis of whether psychological health among American adults has worsened over the past two decades. Here, we use data from national samples of adults in the mid-1990s and early 2010s to demonstrate increasing distress and declining well-being that was concentrated among low-socioeconomic-status individuals but spanned the age range from young to older adults.
Abstract
Although there is little dispute about the impact of the US opioid epidemic on recent mortality, there is less consensus about whether trends reflect increasing despair among American adults. The issue is complicated by the absence of established scales or definitions of despair as well as a paucity of studies examining changes in psychological health, especially well-being, since the 1990s. We contribute evidence using two cross-sectional waves of the Midlife in the United States (MIDUS) study to assess changes in measures of psychological distress and well-being. These measures capture negative emotions such as sadness, hopelessness, and worthlessness, and positive emotions such as happiness, fulfillment, and life satisfaction. Most of the measures reveal increasing distress and decreasing well-being across the age span for those of low relative socioeconomic position, in contrast to little decline or modest improvement for persons of high relative position.

Wednesday, July 11, 2018

A fundamental advance in brain imaging techniques.

I want to pass on the abstract, along with a bit of text and two figures, from an article by Coalson, Van Essen, and Glasser that argues for a fundamental change is how functional cortical areas of the brain are recorded and reported.  They demonstrate that surface based parcellation is 3-fold more accurate than traditional volume based parcellations.:

Significance
Most human brain-imaging studies have traditionally used low-resolution images, inaccurate methods of cross-subject alignment, and extensive blurring. Recently, a high-resolution approach with more accurate alignment and minimized blurring was used by the Human Connectome Project to generate a multimodal map of human cortical areas in hundreds of individuals. Starting from these data, we systematically compared these two approaches, showing that the traditional approach is nearly three times worse than the Human Connectome Project’s improved approach in two objective measures of spatial localization of cortical areas. Furthermore, we demonstrate considerable challenges in comparing data across the two approaches and, as a result, argue that there is an urgent need for the field to adopt more accurate methods of data acquisition and analysis.
Abstract
Localizing human brain functions is a long-standing goal in systems neuroscience. Toward this goal, neuroimaging studies have traditionally used volume-based smoothing, registered data to volume-based standard spaces, and reported results relative to volume-based parcellations. A novel 360-area surface-based cortical parcellation was recently generated using multimodal data from the Human Connectome Project, and a volume-based version of this parcellation has frequently been requested for use with traditional volume-based analyses. However, given the major methodological differences between traditional volumetric and Human Connectome Project-style processing, the utility and interpretability of such an altered parcellation must first be established. By starting from automatically generated individual-subject parcellations and processing them with different methodological approaches, we show that traditional processing steps, especially volume-based smoothing and registration, substantially degrade cortical area localization compared with surface-based approaches. We also show that surface-based registration using features closely tied to cortical areas, rather than to folding patterns alone, improves the alignment of areas, and that the benefits of high-resolution acquisitions are largely unexploited by traditional volume-based methods. Quantitatively, we show that the most common version of the traditional approach has spatial localization that is only 35% as good as the best surface-based method as assessed using two objective measures (peak areal probabilities and “captured area fraction” for maximum probability maps). Finally, we demonstrate that substantial challenges exist when attempting to accurately represent volume-based group analysis results on the surface, which has important implications for the interpretability of studies, both past and future, that use these volume-based methods.
Some context from their introduction:
The recently reported HCP-MMP1.0 multimodal cortical parcellation (https://balsa.wustl.edu/study/RVVG, see the graphic below) contains 180 distinct areas per hemisphere and was generated from hundreds of healthy young adult subjects from the Human Connectome Project (HCP) using data precisely aligned with the HCP’s surface-based neuroimaging analysis approach. Each cortical area is defined by multiple features, such as those representing architecture, function, connectivity, or topographic maps of visual space. This multimodal parcellation has generated widespread interest, with many investigators asking how to relate its cortical areas to data processed using the traditional neuroimaging approach. Because volume-registered analysis of the cortex in MNI space is still widely used, this has often translated into concrete requests, such as: “Please provide the HCP-MMP1.0 parcellation in standard MNI volume space.” Here, we investigate quantitatively the drawbacks of traditional volume-based analyses and document that much of the HCP-MMP1.0 parcellation cannot be faithfully represented when mapped to a traditional volume-based atlas.
Here is a graphic from the parcellation analysis


And here is Figure 1 and its explanation from the Coalson et al. paper.


The figure shows a probabilistic maps of five exemplar areas spanning a range of peak probabilities. Each area is shown as localized by areal-feature–based surface registration (Lower, Center), and as localized by volume-based methods. One area (3b in Fig. 1) has a peak probability of 0.92 in the volume (orange, red), whereas the other four have volumetric peak probabilities in the range of 0.35–0.7 (blue, yellow). Notably, the peak probabilities of these five areas are all higher on the surface (Figure, Lower, Center) (range 0.90–1) than in the volume, indicating that MSMAll nonlinear surface-based registration provides substantially better functional alignment across subjects than does nonlinear volume-based registration.

Tuesday, July 10, 2018

Mindfulness training increases strength of right insula connections.

Sharp et al.(open source) suggest that:
The endeavor to understand how mindfulness works will likely be advanced by using recently developed tools and theory within the nascent field of brain connectomics. The connectomic framework conceives of the brain’s functional and structural architecture as a complex, dynamic network. This network view of brain function partly arose from the lack of support for highly selective, modular regions instantiating specialized functions. That is, large meta-analyses consisting mostly of univariate fMRI analyses disconfirm that, for example, the amygdala is exclusively selective for fear processing. Indeed, more fruitful mechanistic knowledge of how neural systems function may emerge from delineating how different regions communicate functionally across a range of environments, and by identifying the underlying structural connections that constrain such functional dynamics.
Their abstract, and a summary figure:
Although mindfulness meditation is known to provide a wealth of psychological benefits, the neural mechanisms involved in these effects remain to be well characterized. A central question is whether the observed benefits of mindfulness training derive from specific changes in the structural brain connectome that do not result from alternative forms of experimental intervention. Measures of whole-brain and node-level structural connectome changes induced by mindfulness training were compared with those induced by cognitive and physical fitness training within a large, multi-group intervention protocol (n = 86). Whole-brain analyses examined global graph-theoretical changes in structural network topology. A hypothesis-driven approach was taken to investigate connectivity changes within the insula, which was predicted here to mediate interoceptive awareness skills that have been shown to improve through mindfulness training. No global changes were observed in whole-brain network topology. However, node-level results confirmed a priori hypotheses, demonstrating significant increases in mean connection strength in right insula across all of its connections. Present findings suggest that mindfulness strengthens interoception, operationalized here as the mean insula connection strength within the overall connectome. This finding further elucidates the neural mechanisms of mindfulness meditation and motivates new perspectives about the unique benefits of mindfulness training compared to contemporary cognitive and physical fitness interventions.
Legend - Anatomical representation of tractography pathways between right insula and highly connected regions. Connections displayed (only corticocortical, here) comprised the top 80% connection strengths across all insula pathways. (A) Displays pre-training connections in right insula, which showed the greatest structural reorganization across mindfulness training. (B) Represents the same image as in (A) except at post-training.

Monday, July 09, 2018

Mortality rates level off at extreme age

Interesting work from Barbi et al. showing that human death rates increase exponentially up to about age 80, then decelerate, and plateau after age 105. At that point, the odds of someone dying from one birthday to the next are roughly 50:50. This implies that there might be no natural limit to how long humans can live, contrary to the view of most demographers and biologists.:
Theories about biological limits to life span and evolutionary shaping of human longevity depend on facts about mortality at extreme ages, but these facts have remained a matter of debate. Do hazard curves typically level out into high plateaus eventually, as seen in other species, or do exponential increases persist? In this study, we estimated hazard rates from data on all inhabitants of Italy aged 105 and older between 2009 and 2015 (born 1896–1910), a total of 3836 documented cases. We observed level hazard curves, which were essentially constant beyond age 105. Our estimates are free from artifacts of aggregation that limited earlier studies and provide the best evidence to date for the existence of extreme-age mortality plateaus in humans.

Friday, July 06, 2018

Brain imaging predicts who will be a good musical performer.

Fascinating observations from Zatorre's group:

Significance
In sophisticated auditory–motor learning such as musical instrument learning, little is understood about how brain plasticity develops over time and how the related individual variability is reflected in the neural architecture. In a longitudinal fMRI training study on cello learning, we reveal the integrative function of the dorsal cortical stream in auditory–motor information processing, which comes online quickly during learning. Additionally, our data show that better performers optimize the recruitment of regions involved in auditory encoding and motor control and reveal the critical role of the pre-supplementary motor area and its interaction with auditory areas as predictors of musical proficiency. The present study provides unprecedented understanding of the neural substrates of individual learning variability and therefore has implications for pedagogy and rehabilitation.
Abstract
The auditory and motor neural systems are closely intertwined, enabling people to carry out tasks such as playing a musical instrument whose mapping between action and sound is extremely sophisticated. While the dorsal auditory stream has been shown to mediate these audio–motor transformations, little is known about how such mapping emerges with training. Here, we use longitudinal training on a cello as a model for brain plasticity during the acquisition of specific complex skills, including continuous and many-to-one audio–motor mapping, and we investigate individual differences in learning. We trained participants with no musical background to play on a specially designed MRI-compatible cello and scanned them before and after 1 and 4 wk of training. Activation of the auditory-to-motor dorsal cortical stream emerged rapidly during the training and was similarly activated during passive listening and cello performance of trained melodies. This network activation was independent of performance accuracy and therefore appears to be a prerequisite of music playing. In contrast, greater recruitment of regions involved in auditory encoding and motor control over the training was related to better musical proficiency. Additionally, pre-supplementary motor area activity and its connectivity with the auditory cortex during passive listening before training was predictive of final training success, revealing the integrative function of this network in auditory–motor information processing. Together, these results clarify the critical role of the dorsal stream and its interaction with auditory areas in complex audio–motor learning.