Showing posts with label human development. Show all posts
Showing posts with label human development. Show all posts

Friday, July 12, 2019

The Problem With ‘Sharenting’

An article in the NYTimes 'Privacy Project' by Kamenetz resonates with my own experience of very mixed reactions to viewing some of what I consider the most private and intimate details of the lives of my 5 and 7 year old grandsons occasionally revealed in some of the Facebook posts by their parents. I feel embarrassed for the boys, and sometimes how they would feel in their 20s and 30s if they were to look back at these posts on their childhood. (A pre-facebook version of the situation from my childhood is a photograph of two legs - five year old Deric - protruding from under a newspaper sitting on the toilet...how cute!). Some clips from the Kamenetz piece:
Today, many children’s social media presence starts with a sonogram, posted, obviously, without consent. One study from Britain found that nearly 1,500 images of the average child had been placed online by their fifth birthday. Parents get a lot of gratification from telling kids’ stories online...It’s less clear what our children have to gain from their lives being broadcast in this way. ..parents’ rights to free speech and self-expression are at odds with children’s rights to privacy when they are young and vulnerable...This is especially true when the information is potentially damaging. Imagine a child who has behavior problems, learning disabilities or chronic illness. Mom or Dad understandably want to discuss these struggles and reach out for support. But those posts live on the internet, with potential to be discovered by college admissions officers and future employers, friends and romantic prospects. A child’s life story is written for him before he has a chance to tell it himself.
Even if you confine your posts about your children to sunny days and birthday parties, any information you provide about them — names, dates of birth, geographic location — could be acquired by data brokersClose X, companies that collect personal information and sell it to advertisers.
Finally, there’s display and commodification. In 2018, the top earner on YouTube, according to Forbes, was a 7-year-old boy who brought in $22 million by playing with toys. It’s never seemed more accessible to become famous at a wee age, and the type of children who used to sing into a hairbrush in the mirror are often clamoring to start their own channels today.
The most egregious abuses are just the tip of the iceberg, though. For every moneymaking influencer, there are millions of less-successful stage parents and wannabes scratching for followers on YouTube and Instagram. They’re out there shoving cameras in children’s faces, using up their free time, killing spontaneity, warping the everyday rituals of childhood into long working shoots.
When it comes to childhood and technology, we adults are the horror show.

Monday, July 08, 2019

Subgroups of gay men correspond to different biodevelopmental pathways

Swift-Gallant et al. consider three established biomarkers of sexual orientation and suggest they reflect distinct biodevelopmental pathways influencing same-sex sexual orientation in men. They describe these biomarkers in their introduction:
A well-established biomarker of sexual orientation is familiality of male same-sex sexual orientation. Same-sex sexual orientation clusters in families, twin studies show greater sexual orientation concordance among monozygotic than dizygotic twins, and molecular genetic studies have identified candidate genes associated with sexual orientation.
A second well-studied biomarker of sexual orientation is handedness. Although the biological underpinnings of handedness are not yet clear, increasing evidence suggests that handedness is a marker of cerebral lateralization determined prenatally by genetic, immunological, and endocrine mechanisms and/or by developmental instability... it is estimated that men have 20% greater odds of non−right-handedness than women, and gay men have 34% greater odds of being non−right-handed than heterosexual men.
A third well-established biomarker of sexual orientation is the fraternal birth order effect). Across a diverse range of cultures and sample types, studies have shown that older brothers increase the odds of androphilia in later-born males. The maternal immune hypothesis is the best-developed explanation of the fraternal birth order effect. It argues that male antigens enter maternal circulation during the gestation and birthing of male offspring, promoting an immune response to these male-specific antigens that increases with each successive male fetus gestated; thus, with each successive pregnancy with a male fetus, the odds increase that these maternal antibodies will affect sexual differentiation of the brain and behavior, including sexual preferences.
Their Significance and Abstract statements:  

Significance
Studying individual differences in gender and sexual orientation provides insight into how early-life biology shapes brain and behavior. The literature identifies multiple biodevelopmental influences on male sexual orientation, but these influences are generally studied individually, and the potential for association or interaction between them remains largely unexplored. We hypothesized that distinct biodevelopmental pathways correspond to specific subgroups of nonheterosexual men. We present evidence that nonheterosexual men can be categorized into at least four subgroups based on established biomarkers, and these biodevelopmental pathways differentially relate to gender expression and personality traits. These findings indicate individual differences in biodevelopmental pathways of male sexual orientation. They also illustrate the value of latent profile analyses for studying individual differences.
Abstract
Several biological mechanisms have been proposed to influence male sexual orientation, but the extent to which these mechanisms cooccur is unclear. Putative markers of biological processes are often used to evaluate the biological basis of male sexual orientation, including fraternal birth order, handedness, and familiality of same-sex sexual orientation; these biomarkers are proxies for immunological, endocrine, and genetic mechanisms. Here, we used latent profile analysis (LPA) to assess whether these biomarkers cluster within the same individuals or are present in different subgroups of nonheterosexual men. LPA defined four profiles of men based on these biomarkers: 1) A subgroup who did not have these biomarkers, 2) fraternal birth order, 3) handedness, and 4) familiality. While the majority of both heterosexual and nonheterosexual men were grouped in the profile that did not have any biomarker, the three profiles associated with a biomarker were composed primarily of nonheterosexual men. We then evaluated whether these subgroups differed on measures of gender nonconformity and personality that reliably show male sexual orientation differences. The subgroup without biomarkers was the most gender-conforming whereas the fraternal birth order subgroup was the most female-typical and agreeable, compared with the other profiles. Together, these findings suggest there are multiple distinct biodevelopmental pathways influencing same-sex sexual orientation in men.

Friday, May 31, 2019

After brief music training 8-10 year old kids show less hyperactivity and better inhibitory control.

Fasano et al. show that only three months of orchestral music training improves inhibitory control and reduces hyperactivity in 8-10 year old children. From the Science Magazine summary of Tamela Hines:
Play your notes and nothing extra. Wait during your measures of rest. Watch the conductor and synchronize with your neighbors. Such attention and sensorimotor skills are key to performing music as part of a group, whether orchestral or choral or a marching band. Not everyone, however, has the time and interest to become a professional musician. Fasano et al. tested the effect of a short orchestral training program, spanning 10 sessions over 3 months, on a group of psychologically normal schoolchildren in Italy. Children in this brief program improved on measures of inhibitory control and hyperactivity. The results suggest new, and fun, ways to help children manage their own hyperactive behaviors.

Wednesday, May 15, 2019

Father's physical activity directly enhances offspring's brain physiology and cognition.

Experiments on mice suggest that human kids of athletic fathers might have more smarts than kids of couch potatoes. From McGreevy et al.:

Significance
Physical exercise is well known for its positive effects on general health (specifically, on brain function and health), and some mediating mechanisms are also known. A few reports have addressed intergenerational inheritance of some of these positive effects from exercised mothers or fathers to the progeny, but with scarce results in cognition. We report here the inheritance of moderate exercise-induced paternal traits in offspring’s cognition, neurogenesis, and enhanced mitochondrial activity. These changes were accompanied by specific gene expression changes, including gene sets regulated by microRNAs, as potential mediating mechanisms. We have also demonstrated a direct transmission of the exercise-induced effects through the fathers’ sperm, thus showing that paternal physical activity is a direct factor driving offspring’s brain physiology and cognitive behavior.
Abstract
Physical exercise has positive effects on cognition, but very little is known about the inheritance of these effects to sedentary offspring and the mechanisms involved. Here, we use a patrilineal design in mice to test the transmission of effects from the same father (before or after training) and from different fathers to compare sedentary- and runner-father progenies. Behavioral, stereological, and whole-genome sequence analyses reveal that paternal cognition improvement is inherited by the offspring, along with increased adult neurogenesis, greater mitochondrial citrate synthase activity, and modulation of the adult hippocampal gene expression profile. These results demonstrate the inheritance of exercise-induced cognition enhancement through the germline, pointing to paternal physical activity as a direct factor driving offspring’s brain physiology and cognitive behavior.

Friday, April 05, 2019

The life prospects of female co-twins are diminished by prenatal testosterone from their male twins.

From Bütikofe et al.:
During sensitive periods in utero, gonadal steroids help organize biological sex differences in humans and other mammals. In litter-bearing species, chromosomal females passively exposed to prenatal testosterone from male littermates exhibit altered physical and behavioral traits as adults. The consequences of such effects are less well understood in humans, but recent near-doubling of twinning rates in many countries since 1980, secondary to advanced maternal age and increased reliance on in vitro fertilization, means that an increasing subset of females in many populations may be exposed to prenatal testosterone from their male co-twin. Here we use data on all births in Norway (n = 728,842, including 13,800 twins) between 1967 and 1978 to show that females exposed in utero to a male co-twin have a decreased probability of graduating from high school (15.2%), completing college (3.9%), and being married (11.7%), and have lower fertility (5.8%) and life-cycle earnings (8.6%). These relationships remain unchanged among the subsets of 583 and 239 females whose male co-twin died during the first postnatal year and first 28 days of life, respectively, supporting the interpretation that they are due primarily to prenatal exposure rather than to postnatal socialization effects of being raised with a male sibling. Our findings provide empirical evidence, using objectively measured nation-level data, that human females exposed prenatally to a male co-twin experience long-term changes in marriage, fertility, and human capital. These findings support the hypothesis of in utero testosterone transfer between twins, which is likely affecting a small but growing subset of females worldwide.

Monday, April 01, 2019

Infants and toddlers expect different third party punishment behaviors from ingroup and outgroup members.

Yet another example of how our brains are wired to distinguish ingroup and outgroup at a very early age...Ting et al. find sophisticated social analysis performed by 1- and 2.5-year-olds, who show different expectations of the behavior of a third party who has viewed an ingroup-outgroup versus an ingroup-ingroup transgression:

Significance
Adults are more likely to punish transgressions that do not affect them when these transgressions victimize ingroup members. Such third-party punishment (TPP) often takes an indirect form, such as the withholding of help. Building on these results, we showed 2.5- and 1-year-olds scenarios involving a wrongdoer, a victim, and a bystander, and we manipulated the minimal-group memberships of the wrongdoer and the victim relative to that of the bystander. When the victim belonged to the bystander’s group, children expected TPP: They detected a violation when the bystander chose to help the wrongdoer. When the victim did not belong to the bystander’s group, however, children no longer expected TPP. Young children thus selectively expect indirect TPP for harm to ingroup members.
Abstract
Adults and older children are more likely to punish a wrongdoer for a moral transgression when the victim belongs to their group. Building on these results, in violation-of-expectation experiments (n = 198), we examined whether 2.5-year-old toddlers (Exps. 1 and 2) and 1-year-old infants (Exps. 3 and 4) would selectively expect an individual in a minimal group to engage in third-party punishment (TPP) for harm to an ingroup victim. We focused on an indirect form of TPP, the withholding of help. To start, children saw a wrongdoer steal a toy from a victim while a bystander watched. Next, the wrongdoer needed assistance with a task, and the bystander either helped or hindered her. The group memberships of the wrongdoer and the victim were varied relative to that of the bystander and were marked with either novel labels (Exps. 1 and 2) or novel outfits (Exps. 3 and 4). When the victim belonged to the same group as the bystander, children expected TPP: At both ages, they detected a violation when the bystander chose to help the wrongdoer. Across experiments, this effect held whether the wrongdoer belonged to the same group as the bystander and the victim or to a different group; it was eliminated when the victim belonged to a different group than the bystander, when groups were not marked, and when either no theft occurred or the wrongdoer was unaware of the theft. Toddlers and infants thus expect individuals to refrain from helping an ingroup victim’s aggressor, providing further evidence for an early-emerging expectation of ingroup support.

Thursday, February 21, 2019

Watching social influence start to bias perceptual integration as children develop

From Large et al.:
The opinions of others have a profound influence on decision making in adults. The impact of social influence appears to change during childhood, but the underlying mechanisms and their development remain unclear. We tested 125 neurotypical children between the ages of 6 and 14 years on a perceptual decision task about 3D-motion figures under informational social influence. In these children, a systematic bias in favor of the response of another person emerged at around 12 years of age, regardless of whether the other person was an age-matched peer or an adult. Drift diffusion modeling indicated that this social influence effect in neurotypical children was due to changes in the integration of sensory information, rather than solely a change in decision behavior. When we tested a smaller cohort of 30 age- and IQ-matched autistic children on the same task, we found some early decision bias to social influence, but no evidence for the development of systematic integration of social influence into sensory processing for any age group. Our results suggest that by the early teens, typical neurodevelopment allows social influence to systematically bias perceptual processes in a visual task previously linked to the dorsal visual stream. That the same bias did not appear to emerge in autistic adolescents in this study may explain some of their difficulties in social interactions.

Monday, January 28, 2019

Homo Prospectus - the brain as a time traveler - augmentation by A.I.?

Steve Johnson does an engaging article on the discovery and significance of the default mode network of our brains, which has been the subject of numerous MindBlog posts. This system recruits association cortices of the brain that are the last to become fully operational and our brain development continues through early adulthood, into our 20s. It is central to our internal mind wandering between past, present, and future.
...this aptitude for cognitive time travel, revealed by the discovery of the default network, may be the defining property of human intelligence. “What best distinguishes our species,” Seligman wrote in a Times Op-Ed with John Tierney, “is an ability that scientists are just beginning to appreciate: We contemplate the future.” He went on: “A more apt name for our species would be Homo prospectus, because we thrive by considering our prospects. The power of prospection is what makes us wise.”
Johnson discusses the augmentation of our future predicting by A.I. algorithms:
Accurate weather forecasting is merely one early triumph of software-based time travel: algorithms that allow us to peer into the future in ways that were impossible just a few decades ago...In machine-learning systems, algorithms can be trained to generate remarkably accurate predictions of future events by combing through vast repositories of data from past events. An algorithm might be trained to predict future mortgage defaults by analyzing thousands of home purchases and the financial profiles of the buyers, testing its hypotheses by tracking which of those buyers ultimately defaulted.
Machine-learning systems will also be immensely helpful when mulling decisions that potentially involve a large number of distinct options. Humans are remarkably adept at building imagined futures for a few competing timelines simultaneously: the one in which you take the new job, the one in which you turn it down. But our minds run up against a computational ceiling when they need to track dozens or hundreds of future trajectories. The prediction machines of A.I. do not have that limitation, which will make them tantalizingly adept at assisting with some meaningful subset of important life decisions in which there is rich training data and a high number of alternate futures to analyze.
These algorithms can help correct a critical flaw in the default network: Human beings are famously bad at thinking probabilistically. The pioneering cognitive psychologist Amos Tversky once joked that where probability is concerned, humans have three default settings: “gonna happen,” “not gonna happen” and “maybe.” We are brilliant at floating imagined scenarios and evaluating how they might make us feel, were they to happen. But distinguishing between a 20 percent chance of something happening and a 40 percent chance doesn’t come naturally to us. Algorithms can help us compensate for that cognitive blind spot.
Whether you find the idea of augmenting the default network thrilling or terrifying, one thing should be clear: These tools are headed our way. In the coming decade, many of us will draw on the forecasts of machine learning to help us muddle through all kinds of life decisions: career changes, financial planning, hiring choices. These enhancements could well turn out to be the next leap forward in the evolution of Homo prospectus, allowing us to see into the future with more acuity — and with a more nuanced sense of probability — than we can do on our own. But even in that optimistic situation, the power embedded in these new algorithms will be extraordinary, which is why Ludwig and many other members of the A.I. community have begun arguing for the creation of open-source algorithms, not unlike the open protocols of the original internet and World Wide Web. Drawing on predictive algorithms to shape important personal or civic decisions will be challenging enough without the process’s potentially being compromised or subtly redirected by the dictates of advertisers. If you thought Russian troll farms were dangerous in our social-media feeds, imagine what will happen when they infiltrate our daydreams.
TODAY, IT SEEMS, mind-wandering is under attack from all sides. It’s a common complaint that our compulsive use of smartphones is destroying our ability to focus. But seen through the lens of Homo prospectus, ubiquitous computing poses a different kind of threat: Having a network-connected supercomputer in your pocket at all times gives you too much to focus on. It cuts into your mind-wandering time. The downtime between cognitively active tasks that once led to REST states can now be filled with Instagram, or Nasdaq updates, or podcasts. We have Twitter timelines instead of time travel. At the same time, a society-wide vogue for “mindfulness” encourages us to be in the moment, to think of nothing at all instead of letting our thoughts wander. Search YouTube, and there are hundreds of meditation videos teaching you how to stop your mind from doing what it does naturally. The Homo prospectus theory suggests that, if anything, we need to carve out time in our schedule — and perhaps even in our schools — to let minds drift.
According to Marcus Raichle at Washington University, it may not be too late to repair whatever damage we may have done to our prospective powers. A few early studies suggest that the neurons implicated in the default network have genetic profiles that are often associated with long-term brain plasticity, that most treasured of neural attributes. “The brain’s default-mode network appears to preserve the capacity for plasticity into adulthood,” he told me. Plasticity, of course, is just another way of saying that the network can learn new tricks. If these new studies pan out, our mind-wandering skills will not have been locked into place in our childhood. We can get better at daydreaming, if we give ourselves the time to do it.
What will happen to our own time-traveling powers as we come to rely more on the prediction machines of A.I.? The outcome may be terrifying, or liberating, or some strange hybrid of the two. Right now it seems inevitable that A.I. will transform our prospective powers in meaningful new ways, for better or for worse. But it would be nice to think that all the technology that helped us understand the default network in the first place also ended up pushing us back to our roots: giving our minds more time to wander, to slip the surly bonds of now, to be out of the moment.

Wednesday, December 12, 2018

Testing theories of sex differences and autism with big data.

From Greenberg et al:

Significance
In the largest study to date of autistic traits, we test 10 predictions from the Empathizing–Systemizing (E-S) theory of sex differences and the Extreme Male Brain (EMB) theory of autism. We confirmed that typical females on average are more empathic, typical males on average are more systems-oriented, and autistic people on average show a “masculinized” profile. The strengths of the study are the inclusion of a replication sample and the use of big data. These two theories can be considered to have strong support. We demonstrate that D-scores (difference between E and S) account for 19 times the variance in autistic traits than do other demographic variables, including sex, underscoring the importance of brain types in autism.
Abstract
The Empathizing–Systemizing (E-S) theory of typical sex differences suggests that individuals may be classified based on empathy and systemizing. An extension of the E-S theory, the Extreme Male Brain (EMB) theory suggests that autistic people on average have a shift towards a more masculinized brain along the E-S dimensions. Both theories have been investigated in small sample sizes, limiting their generalizability. Here we leverage two large datasets (discovery n = 671,606, including 36,648 autistic individuals primarily; and validation n = 14,354, including 226 autistic individuals) to investigate 10 predictions of the E-S and the EMB theories. In the discovery dataset, typical females on average showed higher scores on short forms of the Empathy Quotient (EQ) and Sensory Perception Quotient (SPQ), and typical males on average showed higher scores on short forms of the Autism Spectrum Quotient (AQ) and Systemizing Quotient (SQ). Typical sex differences in these measures were attenuated in autistic individuals. Analysis of “brain types” revealed that typical females on average were more likely to be Type E (EQ > SQ) or Extreme Type E and that typical males on average were more likely to be Type S (SQ > EQ) or Extreme Type S. In both datasets, autistic individuals, regardless of their reported sex, on average were “masculinized.” Finally, we demonstrate that D-scores (difference between EQ and SQ) account for 19 times more of the variance in autistic traits (43%) than do other demographic variables including sex. Our results provide robust evidence in support of both the E-S and EMB theories.

Friday, October 19, 2018

It's better to be born rich than gifted.

Andrew Van Dam points to work by Papageorge and Thom use genome based measurements to demonstrate that even though genetic endowments are distributed almost equally among children in low-income and high-income families the least-gifted children of high-income parents graduate from college at higher rates than the most-gifted children of low-income parents.
Thom and Papageorge’s analysis builds on the findings of one of the biggest genome-wide studies yet conducted. Published by a separate team of a dozen authors in Nature Genetics in July, it’s the latest result of a lengthy, ongoing effort to bring genetic analysis to the social sciences.
The Nature Genetics team scanned millions of individual base pairs across 1,131,881 individual genomes for evidence of correlations between genes and years of schooling completed. They synthesized the findings into a single score we can use to predict educational attainment based on genetic factors.
Thom and Papageorge studied the team’s index after it was calculated for a long-running retirement survey sponsored by the Social Security Administration and the National Institute on Aging. About 20,000 of the survey’s respondents, born between 1905 and 1964, provided their DNA along with their responses, which allowed the economists to attach genetic scores individuals’ academic and economic achievements.
Previous attempts to separate academic potential from the advantages given to children of wealthy families relied on measures such as IQ tests, which are biased by parents’ education, occupation and income...Two people who are genetically similar can have strikingly different IQ test scores because the richer ones have invested more in their kids.

Tuesday, October 16, 2018

Health of fathers influences the well-being of their progeny.

Watkins et al. show in mice that a low protein diet during the period of spermatogenesis leads to offspring with disturbed metabolic health:

Significance
Parental health and diet at the time of conception determine the development and life-long disease risk of their offspring. While the association between poor maternal diet and offspring health is well established, the underlying mechanisms linking paternal diet with offspring health are poorly defined. Possible programming pathways include changes in testicular and sperm epigenetic regulation and status, seminal plasma composition, and maternal reproductive tract responses regulating early embryo development. In this study, we demonstrate that paternal low-protein diet induces sperm-DNA hypomethylation in conjunction with blunted female reproductive tract embryotrophic, immunological, and vascular remodeling responses. Furthermore, we identify sperm- and seminal plasma-specific programming effects of paternal diet with elevated offspring adiposity, metabolic dysfunction, and altered gut microbiota.
Abstract
The association between poor paternal diet, perturbed embryonic development, and adult offspring ill health represents a new focus for the Developmental Origins of Health and Disease hypothesis. However, our understanding of the underlying mechanisms remains ill-defined. We have developed a mouse paternal low-protein diet (LPD) model to determine its impact on semen quality, maternal uterine physiology, and adult offspring health. We observed that sperm from LPD-fed male mice displayed global hypomethylation associated with reduced testicular expression of DNA methylation and folate-cycle regulators compared with normal protein diet (NPD) fed males. Furthermore, females mated with LPD males display blunted preimplantation uterine immunological, cell signaling, and vascular remodeling responses compared to controls. These data indicate paternal diet impacts on offspring health through both sperm genomic (epigenetic) and seminal plasma (maternal uterine environment) mechanisms. Extending our model, we defined sperm- and seminal plasma-specific effects on offspring health by combining artificial insemination with vasectomized male mating of dietary-manipulated males. All offspring derived from LPD sperm and/or seminal plasma became heavier with increased adiposity, glucose intolerance, perturbed hepatic gene expression symptomatic of nonalcoholic fatty liver disease, and altered gut bacterial profiles. These data provide insight into programming mechanisms linking poor paternal diet with semen quality and offspring health.

Thursday, October 11, 2018

Digital media and developing minds

I want to point to the Oct. 2 issue of PNAS, which free online access to a Sackler Colloquium on Digital Media and Developing Minds. The place to start is the introductory article by David Meyer, "From savannas to blue-phase LCD screens: Prospects and perils for child development in the Post-Modern Digital Information Age." Some clips from his article:
The Sackler Colloquium “Digital Media and Developing Minds” was an interdisciplinary collaborative endeavor to promote joint interests of the National Academy of Sciences, the Arthur M. Sackler Foundation, and the Institute of Digital Media and Child Development.‡‡ At the colloquium, a select group of media-savvy experts in diverse disciplines assembled to pursue several interrelated goals: (i) reporting results from state-of-the art scientific research; (ii) establishing a dialogue between medical researchers, social scientists, communications specialists, policy officials, and other interested parties who study media effects; and (iii) setting a future research agenda to maximize the benefits, curtail the costs, and minimize the risks for children and teens in the Post-Modern Digital Information Age.
Christakis et al. (36) report on “How early media exposure may affect cognitive function: A review of results from observations in humans and experiments in mice,” reviewing relevant results from empirical studies of humans and animal models that concern how intense environmental stimulation influences neural brain development and behavior.
Lytle et al. (37) report on “Two are better than one: Infant language learning from video improves in the presence of peers,” showing that social copresence with other same-aged peers facilitates 9-mo-old infants’ learning of spoken phonemes through interactions with visual touch screens.
Kirkorian and Anderson (38) report on “Effect of sequential video shot comprehensibility on attentional synchrony: A comparison of children and adults,” using temporally extended eye-movement records to investigate how “top-down” cognitive comprehension processes for interpreting video narratives develop over an age-range from early childhood (4-y-old) to adulthood.
Beyens et al. (39) report on “Screen media use and ADHD-related behaviors: Four decades of research,” systematically surveying representative scientific literature that suggests a modest positive correlation—moderated by variables such as gender and chronic aggressive tendencies—between media use and ADHD-related behaviors, thereby helping pave the way toward future detailed theoretical models of these phenomena.
Prescott et al. (40) report on “Metaanalysis of the relationship between violent video game play and physical aggression over time,” applying sophisticated statistical techniques to assess data from a large cross-cultural sample of studies (n = 24; aggregated participant sample size > 17,000) about associations between video game violence and prospective future physical aggression, which has yielded evidence of small but reliable direct relationships that are largest among Whites, intermediate among Asians, and smallest (unreliable) among Hispanics.
Uncapher and Wagner (41) report on “Minds and brains of media multitaskers: Current findings and future directions,” evaluating whether intensive media multitasking (i.e., engaging simultaneously with multiple media streams; for example, texting friends on smart phones while answering email messages on laptop computers and playing video games on other electronic devices) leads to relatively poor performance on various cognitive tests under single-tasking conditions, which might happen because chronic media multitasking diminishes individuals’ powers of sustained goal-directed attention.
Finally, Katz et al. (42) report on “How to play 20 questions with nature and lose: Reflections on 100 years of brain-training research,” analyzing how and why past research based on various laboratory and real-world approaches to training basic mental processes (e.g., selective attention, working memory, and cognitive control)—including contemporary video game playing (also known as “brain training”)—have yet to yield consistently positive, practically significant, outcomes, such as durable long-term enhancements of general fluid intelligence.

Monday, September 24, 2018

Infants distinguish between leaders and bullies

From Margoni et al:
We examined whether 21-month-old infants could distinguish between two broad types of social power: respect-based power exerted by a leader (who might be an authority figure with legitimate power, a prestigious individual with merited power, or some combination thereof) and fear-based power exerted by a bully. Infants first saw three protagonists interact with a character who was either a leader (leader condition) or a bully (bully condition). Next, the character gave an order to the protagonists, who initially obeyed; the character then left the scene, and the protagonists either continued to obey (obey event) or no longer did so (disobey event). Infants in the leader condition looked significantly longer at the disobey than at the obey event, suggesting that they expected the protagonists to continue to obey the leader in her absence. In contrast, infants in the bully condition looked equally at the two events, suggesting that they viewed both outcomes as plausible: The protagonists might continue to obey the absent bully to prevent further harm, or they might disobey her because her power over them weakened in her absence. Additional results supported these interpretations: Infants expected obedience when the bully remained in the scene and could harm the protagonists if defied, but they expected disobedience when the order was given by a character with little or no power over the protagonists. Together, these results indicate that by 21 months of age, infants already hold different expectations for subordinates’ responses to individuals with respect-based as opposed to fear-based power.

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.

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.

Thursday, May 31, 2018

A.I. needs to learn like a human child.

Matthew Hutson summarizes efforts to nudge machine learning researchers away from the assumption that "computers trained on mountains of data can learn just about anything—including common sense—with few, if any, programmed rules." Some clips from his article:
In February, MIT launched Intelligence Quest, a research initiative now raising hundreds of millions of dollars to understand human intelligence in engineering terms. Such efforts, researchers hope, will result in AIs that sit somewhere between pure machine learning and pure instinct. They will boot up following some embedded rules, but will also learn as they go.
Part of the quest will be to discover what babies know and when—lessons that can then be applied to machines. That will take time, says Oren Etzioni, CEO of the Allen Institute for Artificial Intelligence (AI2) in Seattle, Washington. AI2 recently announced a $125 million effort to develop and test common sense in AI. "We would love to build on the representational structure innate in the human brain," Etzioni says, "but we don't understand how the brain processes language, reasoning, and knowledge."
Harvard University psychologist Elizabeth Spelke has argued that we have at least four "core knowledge" systems giving us a head start on understanding objects, actions, numbers, and space. We are intuitive physicists, for example, quick to understand objects and their interactions...Gary Marcus has composed a minimum list of 10 human instincts that he believes should be baked into AIs, including notions of causality, cost-benefit analysis, and types versus instances (dog versus my dog).
The debate over where to situate an AI on a spectrum between pure learning and pure instinct will continue. But that issue overlooks a more practical concern: how to design and code such a blended machine. How to combine machine learning—and its billions of neural network parameters—with rules and logic isn't clear. Neither is how to identify the most important instincts and encode them flexibly. But that hasn't stopped some researchers and companies from trying.
...researchers are working to inject their AIs with the same intuitive physics that babies seem to be born with. Computer scientists at DeepMind in London have developed what they call interaction networks. They incorporate an assumption about the physical world: that discrete objects exist and have distinctive interactions. Just as infants quickly parse the world into interacting entities, those systems readily learn objects' properties and relationships. Their results suggest that interaction networks can predict the behavior of falling strings and balls bouncing in a box far more accurately than a generic neural network.
Vicarious, a robotics software company in San Francisco, California, is taking the idea further with what it calls schema networks. Those systems, too, assume the existence of objects and interactions, but they also try to infer the causality that connects them. By learning over time, the company's software can plan backward from desired outcomes, as people do. (I want my nose to stop itching; scratching it will probably help.) The researchers compared their method with a state-of-the-art neural network on the Atari game Breakout, in which the player slides a paddle to deflect a ball and knock out bricks. Because the schema network could learn about causal relationships—such as the fact that the ball knocks out bricks on contact no matter its velocity—it didn't need extra training when the game was altered. You could move the target bricks or make the player juggle three balls, and the schema network still aced the game. The other network flailed.
Besides our innate abilities, humans also benefit from something most AIs don't have: a body. To help software reason about the world, Vicarious is "embodying" it so it can explore virtual environments, just as a baby might learn something about gravity by toppling a set of blocks. In February, Vicarious presented a system that looked for bounded regions in 2D scenes by essentially having a tiny virtual character traverse the terrain. As it explored, the system learned the concept of containment, which helps it make sense of new scenes faster than a standard image-recognition convnet that passively surveyed each scene in full. Concepts—knowledge that applies to many situations—are crucial for common sense. "In robotics it's extremely important that the robot be able to reason about new situations," says Dileep George, a co-founder of Vicarious. Later this year, the company will pilot test its software in warehouses and factories, where it will help robots pick up, assemble, and paint objects before packaging and shipping them.
One of the most challenging tasks is to code instincts flexibly, so that AIs can cope with a chaotic world that does not always follow the rules. Autonomous cars, for example, cannot count on other drivers to obey traffic laws. To deal with that unpredictability, Noah Goodman, a psychologist and computer scientist at Stanford University in Palo Alto, California, helps develop probabilistic programming languages (PPLs). He describes them as combining the rigid structures of computer code with the mathematics of probability, echoing the way people can follow logic but also allow for uncertainty: If the grass is wet it probably rained—but maybe someone turned on a sprinkler. Crucially, a PPL can be combined with deep learning networks to incorporate extensive learning. While working at Uber, Goodman and others invented such a "deep PPL," called Pyro. The ride-share company is exploring uses for Pyro such as dispatching drivers and adaptively planning routes amid road construction and game days. Goodman says PPLs can reason not only about physics and logistics, but also about how people communicate, coping with tricky forms of expression such as hyperbole, irony, and sarcasm.

Monday, May 21, 2018

Brain changes from adolescence to adulthood

Kundu et al. have used a new fMRI imaging technique to look at shifts in functional brain organization in subjects ranging from 8 to 46 years old, finding that localized networks characteristic of youth meld into larger and more functionally distinct networks with maturity. The number of blood oxygenation level-dependent (BOLD) components is halved from adolescence to the fifth decade of life, stabilizing in middle adulthood. The regions driving this change are dorsolateral prefrontal cortices, parietal cortex, and cerebellum. More dynamic regions correlate with skills that are works in progress during adolescence - developing a sense of self, monitoring one's performance, and estimating others' intentions.

Thursday, April 19, 2018

Baby Boomers reaching the end of their To-Do list

A few clips from an engaging piece by Patricia Hampl on the maturing of the baby boomer generation, those born in 1946 or later - who came of age during the Vietnam War era. (Born in 1942, I qualify as being on the leading edge of this generation.)
Life, if you’re lucky, is divided into thirds, my father used to say: youth, middle age and “You look good.”...By the time you’ve worked long enough, hard enough, real life begins to reveal itself as something other than effort, other than accomplishment...It’s a late-arriving awareness of consciousness existing for its own sake...in this latter stage of existence, to have only one task: to waste life in order to find it.
...now the boomers are approaching the other side...the other side of striving...The battle between striving and serenity may be distinctly American. The struggle between toil and the dream of ease is an American birthright, the way a Frenchman expects to have decent wine at a reasonable price, and the whole month of August on vacation...The essential American word isn’t happiness. It’s pursuit.
But how about just giving up? What about wasting time? Giving up or perhaps giving over. To what? Perhaps what an earlier age called “the life of the mind,” the phrase that describes the sovereign self at ease, at home in the world. This isn’t the mind of rational thought, but the lost music of wondering, the sheer value of looking out the window, letting the world float along...That’s what that great American lounger Whitman did. “I loaf and invite my soul,” he wrote. “I lean and loaf at my ease, observing a spear of summer grass.” In this way he came to his great conception of national citizenship for Americans, “the dear love of comrades.” His loafing led to solidarity.
Loafing is not a prudent business plan, not even a life plan, not a recognizably American project. But it begins to look a little like happiness, the kind that claims you, unbidden. Stay put and let the world show up? Or get out there and be a flâneur? Which is it? Well, it’s both.
Maybe this is what my father’s third stage of life is about — wondering, rather than pursuing. You look good — meaning, hey, you’re still alive, you’re still here, and for once you don’t really need to have a to-do list.

Wednesday, March 28, 2018

Logic in babies.

Halberda does a commentary on work of Cesana-Arlotti et al. showing that one essential form of logical inference, process of elimination, is with the toolkit of 12 month old infants. They used that fact that visual behaviors - such as a shift in one's gaze or a prolonged stare - can be diagnostic of internal thoughts to demonstrate that preverbal infants can formulate a logical structure called a disjunctive syllogism. That is, if A or B is true, and A is false, then B must be true. Presenting infants with scenes where the outcome revealed B to be false evoked looks of surprise:
Cesana-Arlotti et al. asked whether prelinguistic 12- and 19-month-old infants would spontaneously reason using process of elimination. This is a form of inference also known as disjunctive syllogism or modus tollendo ponens—it is any argument of the form: A or B, not A, therefore B. Cesana-Arlotti et al. relied on one of the few behaviors babies voluntarily engage in—looking at whatever they find most interesting. They measured infants' looking at computerized vignettes in which two different objects (A and B) were shown being hidden behind a wall. Infants watched as a cup scooped one of the objects from behind the wall, and then came to rest next to the wall—critically, only the topmost edge of the contained object could be seen peeking out of the cup, such that infants could not tell for sure whether the object was A or B. At this moment, infants could have formed a disjunctive thought—for example, “either the object in the cup is object A or it is object B.” Next, this ambiguity was resolved: The wall dropped to reveal that object A was behind the wall, but the contents of the cup remained hidden. This is the moment of potential elimination, and an opportunity for infants to draw a key inference—“because object A is not in the cup, object B must be in the cup.” Finally, infants' expectations for the cup's contents were tested: Either the expected object (object B) or, surprisingly, another object A emerged from the cup. Infants looked longer at the surprising outcome—an indication that their expectations were violated and a hint that they were seeking further information to resolve the conflict.

Tuesday, January 02, 2018

How early stress exposure influences adult decision making.

From Birn et al.:
Individuals who have experienced chronic and high levels of stress during their childhoods are at increased risk for a wide range of behavioral problems, yet the neurobiological mechanisms underlying this association are poorly understood. We measured the life circumstances of a community sample of school-aged children and then followed these children for a decade. Those from the highest and lowest quintiles of childhood stress exposure were invited to return to our laboratory as young adults, at which time we reassessed their life circumstances, acquired fMRI data during a reward-processing task, and tested their judgment and decision making. Individuals who experienced high levels of early life stress showed lower levels of brain activation when processing cues signaling potential loss and increased responsivity when actually experiencing losses. Specifically, those with high childhood stress had reduced activation in the posterior cingulate/precuneus, middle temporal gyrus, and superior occipital cortex during the anticipation of potential rewards; reduced activation in putamen and insula during the anticipation of potential losses; and increased left inferior frontal gyrus activation when experiencing an actual loss. These patterns of brain activity were associated with both laboratory and real-world measures of individuals’ risk taking in adulthood. Importantly, these effects were predicated only by childhood stress exposure and not by current levels of life stress.