Functional connectivity shows age-related increases within resting-state networks & age-related decreases between them; genetic influences on functional connectivity remain stable throughout adolescence

Genetic and environmental influences on functional connectivity within and between canonical cortical resting-state networks throughout adolescent development in boys and girls. Jalmar Teeuw et al. NeuroImage, August 3 2019, 116073. https://doi.org/10.1016/j.neuroimage.2019.116073

Highlights
• We studied resting-state networks in a longitudinal adolescent twin-sibling sample.
• Functional connectivity shows age-related increases within resting-state networks.
• Functional connectivity shows age-related decreases between resting-state networks.
• Reliability modelling improves sensitivity to detect familial influences.
• Genetic influences on functional connectivity remain stable throughout adolescence.

Abstract: The human brain is active during rest and hierarchically organized into intrinsic functional networks. These functional networks are largely established early in development, with reports of a shift from a local to more distributed organization during childhood and adolescence. It remains unknown to what extent genetic and environmental influences on functional connectivity change throughout adolescent development. We measured functional connectivity within and between eight cortical networks in a longitudinal resting-state fMRI study of adolescent twins and their older siblings on two occasions (mean ages 13 and 18 years). We modelled the reliability for these inherently noisy and head-motion sensitive measurements by analyzing data from split-half sessions. Functional connectivity between resting-state networks decreased with age whereas functional connectivity within resting-state networks generally increased with age, independent of general cognitive functioning. Sex effects were sparse, with stronger functional connectivity in the default mode network for girls compared to boys, and stronger functional connectivity in the salience network for boys compared to girls. Heritability explained up to 53% of the variation in functional connectivity within and between resting-state networks, and common environment explained up to 33%. Genetic influences on functional connectivity remained stable during adolescent development. In conclusion, longitudinal age-related changes in functional connectivity within and between cortical resting-state networks are subtle but wide-spread throughout adolescence. Genes play a considerable role in explaining individual variation in functional connectivity with mostly stable influences throughout adolescence.

Keywords: LongitudinalTwinsHeritabilityAge effectsSex effects

A Decline in Propensity Toward Risk Behaviors Among US Adolescents

Borodovsky, Jacob and Krueger, Robert F. and Agrawal, Arpana and Grucza, Richard, A Decline in Propensity Toward Risk Behaviors Among US Adolescents (June 14, 2019). Available at SSRN, http://dx.doi.org/10.2139/ssrn.3403870

Abstract
Purpose: Over the past two decades, substance use, delinquent behaviors, and promiscuous sexual activity have declined substantially among U.S. adolescents. We aimed to determine the extent to which these trends represent declines in a general propensity to engage in risk behaviors (i.e., declines in a latent factor).
Methods: We used Youth Risk Behavior Survey data (1999-2017) (n=147,800) and examined trends in substance use (e.g., alcohol) delinquency (e.g., fighting), and sexual activity (e.g., number of partners). We conducted two types of analyses stratified by grade (9th/10th vs. 11th/12th) and sex: (1) estimation of year-specific prevalence of each behavior and modeled prevalence changes over time; (2) factor analysis and application of alignment methods to determine changes in the mean of the latent factor over time while correcting for measurement non-invariance.
Results: A single factor explained 53% (girls 11th/12th grade) to 62% (boys 9th/10th grade) of the variance in risk behaviors. Average relative annual declines in the prevalence of each behavior—except for weapon carrying—ranged from 1-6%. The structure of the latent factor was mostly unchanged over time, with notable exceptions related to differential changes in prevalence for cigarette and cannabis use. Between 1999 and 2017, the mean of the latent factor declined by between 0.54 and 0.73 standard deviations.
Conclusions: Results suggest that much of the decline in the prevalence of substance use, delinquent, and sexual behaviors among American youth from 1999-2017 reflect an approximately two-thirds standard deviation decline in the mean of a latent risk behavior factor.

Links between distress & time perception suggest the possibility of downward spirals during stressful waiting periods, such that distress makes time seem to slow down, which then exacerbates distress

Associations between Subjective Time Perception and Well‐Being during Stressful Waiting Periods. Kyla Rankin  Kate Sweeny  Sandra Xu. Stress & Health, August 2 2019, https://doi.org/10.1002/smi.2888

Abstract: The passage of time is a subjective experience and can be easily distorted by concurrent emotions. Specifically, time seems to move particularly slowly when people are in a negative emotional state. The aim of the current studies was to evaluate the bidirectional relationship between subjective time perception and distress during stressful waiting periods, during which the slow passage of time may be particularly distressing. Across studies of undergraduate students awaiting a midterm exam grade (Study 1) and law graduates awaiting bar exam results (Studies 2 and 3), results revealed consistent links between distress and time perception across the waiting periods, with tentative evidence for bidirectional relationships between these experiences. That is, people who perceived time as moving slowly while they waited tended to report greater distress across the waiting period (particularly worry, anxiety, negative emotion, and poor coping), and people who reported greater distress tended to perceive time as moving more slowly. The links between distress and time perception suggest the possibility of downward spirals during stressful waiting periods, such that distress makes time seem to slow down, which then exacerbates distress. We discuss avenues for future research and potential remedies to derail the spiral of distress and time perception.

Techniques have been identified that can modify memories at both stages of initial storage and re-storage, but implementation into clinical therapies has produced inconsistent benefits

Memory editing from science fiction to clinical practice. Elizabeth A. Phelps & Stefan G. Hofmann. Nature, volume 572, pages 43–50 (2019). July 31 2019, https://www.nature.com/articles/s41586-019-1433-7

Abstract: Science fiction notions of altering problematic memories are starting to become reality as techniques emerge through which unique memories can be edited. Here we review memory-editing research with a focus on improving the treatment of psychopathology. Studies highlight two windows of memory vulnerability: initial storage, or consolidation; and re-storage after retrieval, or reconsolidation. Techniques have been identified that can modify memories at each stage, but translating these methods from animal models to humans has been challenging and implementation into clinical therapies has produced inconsistent benefits. The science of memory editing is more complicated and nuanced than fiction, but its rapid development holds promise for future applications.

J‐curve association between alcohol intake and varicose veins in Japan: The Shimane CoHRE Study

J‐curve association between alcohol intake and varicose veins in Japan: The Shimane CoHRE Study. Kunie Kohno  Hiroyuki Niihara  Tsuyoshi Hamano  Miwako Takeda  Yusei Nakagawa  Kuninori Shiwaku  Toru Nabika  Bengt Zöller  Xinjun Li  Kristina Sundquist  Jan Sundquist  Eishin Morita. Concise Communication, July 29 2019 https://doi.org/10.1111/1346-8138.15022

Abstract: The effect of alcohol intake on varicose veins (VV) has not been determined by its consumption level. The aim of this study was to investigate the association between alcohol intake and VV in an elderly general population. Using a cross‐sectional approach, the Shimane CoHRE Study data, comprising a total of 1060 participants, were analyzed. By multivariate regression analysis adjusted with basic characteristics, past work history, lifestyle‐related factors and medical history, compared with non‐drinkers, mild drinkers (<20.0 g/day) showed a significantly lower adjusted odds ratio (aOR) of VV (aOR = 0.64, P = 0.036). In a similar way, regular drinkers (1–5 days/week) showed a significantly lower aOR of VV when compared with occasional drinkers (aOR = 0.57, P = 0.032). VV and alcohol intake showed J‐curve relationships. In a stratified analysis by alcohol consumption levels, the association of smoking and VV were also observed in moderate to heavy drinkers and habitual drinkers. These findings can provide better understanding of pathophysiological mechanism and be used for evidence‐based patient education.

Re-analysis of data reveals no evidence for neonatal imitation in rhesus macaques

Re-analysis of data reveals no evidence for neonatal imitation in rhesus macaques. Jonathan Redshaw. Biology Letters, July 24 2019, https://doi.org/10.1098/rsbl.2019.0342

Abstract: Over the past decade, a growing number of publications have claimed to provide evidence for the existence and function of neonatal imitation in rhesus macaques. Here I show that there is in fact no empirical basis for these claims. Studies of the phenomenon have consistently failed to implement the gold standard cross-target analytical approach, which controls for increases in matching responses that may not be a function of the specific modelled behaviour. Critically, a pre-registered re-analysis of the entire set of existing data using this cross-target approach shows that macaque neonates have failed to produce matching tongue protrusion or lipsmacking responses at levels greater than chance. Furthermore, there is no evidence for intra-individual consistency in ‘imitative’ responses across different actions, as imitation scores for the two actions are negatively correlated with each other. Macaque tongue protrusion and lipsmacking responses may vary as a function of general factors that fluctuate over testing sessions, rather than as a function of the specific model or of between-individual variations in imitative tendencies.

Social media comparisons: More likely to be upward than downward, & making more frequent & more extreme upward comparisons yielded greater declines in self-evaluations, mood, & life satisfaction

When Every Day is a High School Reunion: Social Media Comparisons and Self-esteem. Claire Midgley. Psychology School, Toronto Univ. PhD Thesis, Jun 2019. http://hdl.handle.net/1807/95911

Abstract: Although past research has shown that social comparisons made through social media contribute to negative outcomes, little is known about the nature of these comparisons (e.g., domains, direction, and extremity), variables that determine the outcomes of these comparisons (e.g., post valence, perceiver’s self-esteem), and how these comparisons differ from those made in other contexts (e.g. while texting or interacting face to face). In five studies (N=900), I provide the first comprehensive analysis of how individuals make and respond to social comparisons on two different social media platforms (Facebook and Instagram), using comparisons made in real-time while participants browsed their own social media news feeds (Studies 1 and 3), experimenter-generated social media content (Study 2), and reports of comparisons made in various contexts, including social media (Studies 4 and 5). I found that individuals made frequent upward comparisons on social media. Further, social media comparisons were more likely to be upward than downward, and making more frequent and more extreme upward comparisons on social media resulted in greater declines in self-evaluations, mood, and life satisfaction. In addition, individuals with lower self-esteem made more frequent and extreme upward comparisons while browsing social media, resulting in even steeper declines in self-evaluations. Finally, compared to upward comparisons in other contexts, those made on social media were more often to distant (vs. close) targets, more likely to be image-based, and resulted in greater declines in self-evaluations. Together, these studies provide the first insights into the cumulative impact of multiple social comparisons, demonstrate the unique nature of social comparisons made on social media, and clarify the role of self-esteem in online social comparison processes.

Keywords: self-esteem; social comparison; social media

Evaluating the evidential value of empirically supported psychological treatments (ESTs): Failing to strengthen efficacy

Sakaluk, J. K., Williams, A. J., Kilshaw, R. E., & Rhyner, K. T. (2019). Evaluating the evidential value of empirically supported psychological treatments (ESTs): A meta-scientific review. Journal of Abnormal Psychology, 128(6), 500-509. http://dx.doi.org/10.1037/abn0000421

Abstract: Empirically supported treatments (or therapies; ESTs) are the gold standard in therapeutic interventions for psychopathology. Based on a set of methodological and statistical criteria, the APA has assigned particular treatment-diagnosis combinations EST status and has further rated their empirical support as Strong, Modest, and/or Controversial. Emerging concerns about the replicability of research findings in clinical psychology highlight the need to critically examine the evidential value of EST research. We therefore conducted a metascientific review of the EST literature, using clinical trials reported in an existing online APA database of ESTs, and a set of novel evidential value metrics (i.e., rates of misreported statistics, statistical power, R-Index, and Bayes Factors). Our analyses indicated that power and replicability estimates were concerningly low across almost all ESTs, and individually, some ESTs scored poorly across multiple metrics, with Strong ESTs failing to continuously outperform their Modest counterparts. Lastly, we found evidence of improvements over time in statistical power within the EST literature, but not for the strength of evidence of EST efficacy. We describe the implications of our findings for practicing psychotherapists and offer recommendations for improving the evidential value of EST research moving forward.

Participants increased in well-being when they were assigned to act extraverted & decreased when they were assigned to act introverted; changing behavior associated with personality is possible

Margolis, S., & Lyubomirsky, S. (2019). Experimental manipulation of extraverted and introverted behavior and its effects on well-being. Journal of Experimental Psychology: General. http://dx.doi.org/10.1037/xge0000668

Abstract: Research in personality psychology has remained predominantly correlational. For example, 3 decades of research demonstrate a robust cross-sectional relationship between extraversion and positive affect. A handful of studies, however, have examined this link experimentally, showing that extraversion boosts positive affect over short durations. If this is true, behaving in an extraverted manner should be a reliable method for increasing positive affect and, thus, suitable as a well-being-increasing practice. The current study instructed participants to engage in both extraverted and introverted behavior, each for 1 week. Participants increased in well-being when they were assigned to act extraverted and decreased in well-being when they were assigned to act introverted. These findings suggest that changing behavior associated with personality is possible and can impact well-being. More broadly, this study adds to a growing body of research on the potential of experimental methods in personality psychology.

The influential hypothesis that humans imitate from birth – and that this capacity is foundational to social cognition – is currently being challenged from several angles

Individual differences in neonatal ‘imitation' fail to predict early social cognitive behaviour. Jonathan Redshaw  Mark Nielsen  Virginia Slaughter  Siobhan Kennedy‐Costantini  Janine Oostenbroek  Jessica Crimston  Thomas Suddendorf. Developemental Science, August 1 2019, https://doi.org/10.1111/desc.12892 

Abstract: The influential hypothesis that humans imitate from birth – and that this capacity is foundational to social cognition – is currently being challenged from several angles. Most prominently, the largest and most comprehensive longitudinal study of neonatal imitation to date failed to find evidence that neonates copied any of nine actions at any of four time points (Oostenbroek et al., 2016). The authors of an alternative and statistically liberal post‐hoc analysis of these same data (Meltzoff et al., 2017), however, concluded that the infants actually did imitate one of the nine actions: tongue protrusion. In line with the original intentions of this longitudinal study, we here report on whether individual differences in neonatal ‘imitation' predict later‐developing social cognitive behaviours. We measured a variety of social cognitive behaviours in a subset of the original sample of infants (N = 71) during the first 18 months: object‐directed imitation, joint attention, synchronous imitation, and mirror self‐recognition. Results show that, even using the liberal operationalisation, individual scores for neonatal ‘imitation' of tongue protrusion failed to predict any of the later‐developing social cognitive behaviours. The average Spearman correlation was close to zero, mean rs = .027, 95% CI [‐.020, .075], with all Bonferroni adjusted p values > .999. These results run counter to Meltzoff et al.'s rebuttal, and to the existence of a “like me” mechanism that is foundational to human social cognition.

Sibling analysis of 232 mice: Twins were exposed to either enriched or impoverished environments; enrichment was associated with an increase in the heritability of some personality & cognitive traits

Mouse twins separated when young: A history of exploration doubles the heritability of boldness and differentially affects the heritability of measures of learning. Louis D. Matzel et al. Intelligence, Volume 74, May–June 2019, Pages 34-42. https://doi.org/10.1016/j.intell.2019.01.005

Highlights
• A sibling analysis of 232 mice assessed the sensitivity of heritability to environmental history
• Twins were exposed to either enriched or impoverished environments
• Learning, physical, and personality traits were all heritable
• Environmental enrichment was associated with an increase in the heritability of some personality and cognitive traits
• Estimates of heritability can be sensitive to manipulation of environmental history

Abstract: Most quantifiable traits exhibit some degree of heritability. The heritability of physical traits is often high, but the heritability of some personality traits and intelligence can also be highly heritable. Importantly, estimates of heritability can change dramatically depending on such variables as the age or the environmental history of the sample from which the estimate is obtained. Interpretation of these changing estimates is complicated in studies of humans, where (based on correlational observations) environmental variables are hard to directly control or specify. Using laboratory mice, here we could control specific environmental variables. We assessed 58 groups of four full sibling male CD-1 genetically heterogeneous mice (n = 232). Using a standard full-sibling analysis, physical characteristics (body weight and brain weight) were highly heritable (h of body weight = 0.66 on a 0–1 scale), while behaviors indicative of a personality trait (exploration/boldness) and learning abilities (in a passive avoidance and egocentric maze task) were weakly-to-moderately heritable. Half of the siblings from each set of four were housed in an “enriched” environment, which provided extensive and varied opportunities for exploration. This enrichment treatment promoted improvements in learning and a shift toward a more bold personality type. Relative to animals in control (“impoverished” environments), the history of enrichment had significant impact on estimates of heritability. In particular, the heritability of behaviors related to the personality trait (exploration/boldness) more than doubled, and a similar increase was observed for learning (in the passive avoidance task). Physical traits (brain and body weight), however, were insensitive to environmental history (where in both environments, animals received the same diet). These results indicate that heritable traits can be responsive to variations in the environment, and moreover, that estimates of heritability of learning and personality traits are strongly influenced by environments that modulate those traits.

Keywords: HeritabilityLearningEnvironmental enrichmentBoldnessBody weightBrain weight

Paternal biobehavioral influence on the family: Preliminary data from the D.A.D.I.O. Project

Paternal biobehavioral influence on the family: Preliminary data from the D.A.D.I.O. Project. Nikki J Clauss, Erin Harrington, Jennifer Byrd-Craven. Human Behavior and Evolution Society 31st annual meeting. Boston 2019. http://tiny.cc/aa1w6y

Abstract: While research on maternal influence on the family unit has increased in recent years, assessment of the paternal influence remains sparse. The goal of this research was to increase our understanding of paternal influence on the biobehavioral dynamics of the family unit. Participants consisted of 40 family units recruited between 28- and 36-weeks’ gestation. Participants completed 6 monthly questionnaires and an in-home visit when the infant was 4 months of age, during which parents and infants completed semistructured interaction tasks and provided saliva samples. Saliva was assayed for testosterone, progesterone, and cortisol. Results revealed that fathers’ testosterone was associated with father-infant synchrony (p = .03), mother-infant synchrony (p = .02), and marginally with partner synchrony (p = .08). Maternal progesterone responses were correlated with father-infant synchrony and marginally with couple satisfaction (p = .08) Finally, Infant cortisol was inversely correlated with alloparental support (p = .003). Together, results suggest that a more muted testosterone response is associated with maternal sensitive responding, that maternal progesterone and paternal testosterone may serve similar functions in the familial context, and that alloparental support facilitates infant HPA response selectivity.

The duty to vote is more widespread than the duty to be informed and almost half of those who say that they have a moral obligation to vote indicate that they do not have a duty to keep informed

Is It a Duty to Vote and to be Informed? André Blais, Carol Galais, Danielle Mayer. Political Studies Review, August 1, 2019. https://doi.org/10.1177/1478929919865467

Abstract: We know that many people feel that they have a duty to vote in elections, but we know little about what other civic duties they believe they ought to fulfill. In this study, we address the question of whether people feel that they have both a duty to vote and to be informed. We use an original Canadian survey which includes questions about whether respondents construe voting and keeping informed as duties or a matter of choice. We find that the duty to vote is more widespread than the duty to be informed and that almost half of those who say that they have a moral obligation to vote indicate that they do not have a duty to keep informed. The better educated are more likely to feel that they have a moral obligation to both vote and keep informed while younger respondents are more prone to reject both duties.

Keywords: civic duty, duty to vote, duty to be informed, choice

The Embryos of Turtles Can Influence Their Own Sexual Destinies Just by Moving Within the Egg

The Embryos of Turtles Can Influence Their Own Sexual Destinies. Yin-Zi Ye et al. Current Biology, August 1 2019. https://doi.org/10.1016/j.cub.2019.06.038

Highlights
•    By moving within the egg, a turtle embryo can influence its own sex
•    That ability expands the range of nest conditions producing an equal sex ratio
•    Thermoregulation by embryos should buffer populations against climate change

Summary: Sessile organisms with thermally sensitive developmental trajectories are at high risk from climate change. For example, oviparous reptiles with temperature-dependent sex determination (TSD) may experience strong (potentially disastrous) shifts in offspring sex ratio if reproducing females are unable to predict incubation conditions at the time of oviposition. How then have TSD reptile taxa persisted over previous periods of extreme climatic conditions? An ability of embryos to move within the egg to select optimal thermal regimes could buffer ambient extremes, but the feasibility of behavioral thermoregulation by embryos has come under strong challenge. To test this idea, we measured thermal gradients within eggs in semi-natural nests of a freshwater turtle species with TSD, manipulated embryonic thermoregulatory ability, and modeled the effects of embryonic thermoregulation on offspring sex ratios. Behavioral thermoregulation by embryos accelerated development and influenced offspring sex ratio, expanding the range of ambient conditions under which nests produce equal numbers of male and female offspring. Model projections suggest that sex ratio shifts induced by global warming will be buffered by the ability of embryos to influence their sexual destiny via behavioral thermoregulation.

Nonstate actors (environmentally motivated organizations/individuals, tolerated or even covertly sponsored by states) appear to have increasing power, in part due to new technologies that alter actors’ capacities & incentives

Highly decentralized solar geoengineering. Jesse L. Reynolds & Gernot Wagner. Environmental Politics, Jul 29 2019. https://doi.org/10.1080/09644016.2019.1648169

ABSTRACT: Nonstate actors appear to have increasing power, in part due to new technologies that alter actors’ capacities and incentives. Although solar geoengineering is typically conceived of as centralized and state-deployed, we explore highly decentralized solar geoengineering. Done perhaps through numerous small high-altitude balloons, it could be provided by nonstate actors such as environmentally motivated nongovernmental organizations or individuals. Conceivably tolerated or even covertly sponsored by states, highly decentralized solar geoengineering could move presumed action from the state arena to that of direct intervention by nonstate actors, which could in turn, disrupt international politics and pose novel challenges for technology and environmental policy. We conclude that this method appears technically possible, economically feasible, and potentially politically disruptive. Decentralization could, in principle, make control by states difficult, perhaps even rendering such control prohibitively costly and complex.

KEYWORDS: Climate change, solar geoengineering, solar radiation management, nonstate actors, governance