Reaction time measurement errors resulting from the use of CRT displays

Three sources of potential error in reaction time measurement may occur when raster scan CRT displays are used to present stimuli: phosphor persistence, sweep delay, or transmission delay. For most applications, only the third source of error is likely to be significant.     

Emotional and Behavioral Problems Among Impoverished Kenyan Youth: Factor Structure and Sex-Differences

Data on youth emotional and behavioral problems from societies in Sub-Saharan Africa are lacking. This may be due to the fact that few youth mental health assessments have been tested for construct validity of syndrome structure across multicultural societies that include developing countries, and almost none have been tested in Sub-Saharan Africa. The Youth Self-Report (YSR), for example, has shown great consistency of its syndrome structure across many cultures, yet data from only one developing country in Sub-Saharan Africa have been included. In this study, we test the factor structure of YSR syndromes among Kenyan youth ages 11–18 years from an informal settlement in Nairobi, Kenya and examine sex-differences in levels of emotional and behavioral problems. We find the eight syndrome structure of the YSR to fit these data well (Root Mean Square Error of Approximation = 0.049). While Kenyan girls have significantly higher internalizing (Anxious/Depressed, Withdrawn/Depressed, Somatic) problem scores than boys, these differences are of similar magnitude to published multicultural findings. The results support the generalizability of the YSR syndrome structure to Kenyan youth and are in line with multicultural findings supporting the YSR as an assessment of emotional and behavioral problems in diverse societies.     

Attentional biases to threat in social anxiety disorder: time to focus our attention elsewhere?

Background: Cognitive models propose that attentional biases to threat contribute to the maintenance of social anxiety disorder (SAD). However, the specific characteristics of such biases are still object to debate.

Objectives: The current study aimed to disentangle effects of trait and state social anxiety on attention allocation towards social stimuli.

Methods: Participants with SAD (n?=?67) and healthy controls (n?=?62) completed three visual search tasks while their eye movements were recorded. Half of the participants in each group were randomly assigned to a state anxiety induction.

Results: Contrary to our predictions, neither trait nor state social anxiety was associated with a facilitated attention to or a delayed disengagement from threat. However, participants with SAD did show reduced fixation durations for threatening stimuli, indicating an avoidance of threat. Induction of state anxiety led to an increased distractibility by threat.

Conclusions: We suggest that attention allocation in SAD is characterized by an avoidant rather than a vigilant attentional bias. Accordingly, our results contradict previous results that associate SAD with facilitated attention to threat and existing approaches to modify attentional biases, that aim to decrease attention towards threatening stimuli.     

A two-sample test

In certain investigations involving an experimental group and a control group, the effect of the experimental treatment may be expected to manifest itself by increasing the scores of some subjects but by decreasing the scores of other subjects. Examples arise in the area of defensive behavior. Customary tests of differences between means are inappropriate for assessing the existence of effect of the experimental treatment in such cases. A test based on the ranks of the observations is proposed; it will be sensitive to extreme scores (either large or small or both) for experimentals.     

Mother-Child Interactions and Preschoolers’ Emotion Regulation Outcomes: Nurturing Autonomous Emotion Regulation

Emotion regulation is a complex process that begins in infancy and continues through childhood with parents’ support. Early parent-child interactions shape the way children learn emotion management. We took a sociocultural and social learning approach to exploring the specific components of mother-child interactions that are related to mothers’ perceptions of her child’s regulatory ability and the child’s observed emotion regulation. Thirty mothers and their preschool children were recruited from two New England urban areas: one community sample and one head start sample. Dyads engaged in a free play session, children completed an observed compliance task, and mothers completed a set of questionnaires assessing their perceptions of their child’s regulation. Regression analyses revealed that maternal behaviors during free play predicted child’s observed hostility (F _(2,29)?=?3.137, p?<?.05) and mothers’ perceptions of her child’s regulatory ability predicted observed child compliance (F _{(2, 17)}?=?4.990, p?<?.05). Child behaviors during play significantly predicted child’s compliance (F _(3,20)?=?4.722, p?<?.05) and child’s hostility (F _{(1, 26)}?=?9.220, p?<?.001). Maternal modeling and intentional scaffolding as well as perceptions of her child’s regulatory capacity have a powerful impact on her child’s observed regulation. Results indicate that it is particularly important for mothers of preschoolers to support autonomy while guiding socially appropriate behavior. Interventions that target improving mothers’ negative perceptions of their children, educating on appropriate preschool expectations, and facilitating preschoolers’ mature play may help mothers interact with their children in the ways that foster children’s autonomous emotion regulation.     

Characterizing the musical phenotype in individuals with Williams Syndrome.

Williams Syndrome (WS), a neurodevelopmental genetic disorder, is characterized by peaks and valleys in mental function: substantial impairments in cognitive domains such as reasoning, arithmetic ability, and spatial cognition, alongside relatively preserved skills in social domains, face processing, language, and music. We report the results of a comprehensive survey on musical behaviors and background administered to the largest sample of individuals with WS to date (n = 118, mean age = 20.4), and compare the results to those obtained from a control group of typically developing normal individuals (n = 118, mean age = 20.9) and two groups of individuals with other neurodevelopmental genetic disorders, Autism (n = 30, mean age = 18.2) and Down Syndrome (n = 40, mean age = 17.2). Individuals with WS were found to be rated higher in musical accomplishment, engagement, and interest than either of the comparison groups, and equivalent on most measures to the control group. Compared to all other groups including the controls, the WS individuals displayed greater emotional responses to music, manifested interest in music at an earlier age, and spent more hours per week listening to music. In addition, the effects of music listening (whether positive or negative) tended to last longer in the WS group. A factor analysis extracted seven principal components that characterize the musical phenotype in our sample, and discriminant function analysis of those factors was able to successfully predict group membership for the majority of cases. We discuss the neurobiological implications of these findings.