The tau-dot hypothesis states that when tau-dot greater than or equal to -0.5, impact will be soft; when tau-dot < -0.5, impact will be "hard." Four experiments tested the usefulness of tau-dot for observers of collisions between 2 objects (rather than collisions between the observer and an object). Observers watched collisions depicted on a computer as 1 object approaching another. Results conformed to the tau-dot hypothesis and were consistent with previous research wherein observers watched collisions as participants. Results suggest that the information specifying collision severity is the rate of the relative rate of optical variation, a quantity that remains invariant over differing collision path trajectories and over differing perceivers (i.e., spectators or participants, viewing from different vantage points, moving or stationary). 相似文献
Compulsive sexual behavior (CSB) is defined as difficulties in controlling inappropriate or excessive sexual fantasies, urges, or behaviors that cause subjective distress or impairment in important areas of daily functioning. Using data from a baseline telephone interview, we examined the prevalence of CSB in a convenience sample of 820 postdeployed U.S. military male and female veterans and investigated correlates of CSB with sociodemographics and other mental health and sexual history characteristics. More men (13.8%) than women (4.3%) endorsed CSB-related symptoms. Given the limited sample size of women reporting CSB, correlational analyses were conducted only with men. After adjusting for significant sociodemographics, results indicated that gambling, suicidality, and sexually transmitted infections were significantly associated with male CSB. Current results suggest that CSB may be prevalent among U.S. military veterans post deployment and associated with significant negative health indices in men. CSB warrants attention regarding screening and intervention. 相似文献
Mixed results of the impact of transcranial direct current stimulation (tDCS) on working memory have been reported. Contrarily to previous studies who focused mainly on stimulating the dorsolateral prefrontal cortex, we modulated the left intraparietal sulcus (IPS) area which is considered to support attentional control aspects of working memory. Using a within-participant experimental design, participants completed three different conditions: anodal stimulation of the IPS, cathodal stimulation of the IPS, and sham stimulation of the IPS. Both visual and verbal working memory tasks were administered. In the visual task, participants had to memorize a random set of colored figures. In the verbal task, participants had to memorize a string of letters. Working memory load was manipulated in both tasks (six figures/letters vs. two figures/letters). No significant differences in accuracy or reaction time between the anodal, cathodal and sham conditions were found. Bayesian analysis supported evidence for an absence of effect. The results of the present study add to the growing body of contradictory evidence regarding the modulatory effects of single session tDCS on working memory performance. 相似文献
Despite its transdiagnostic significance, there is modest evidence with respect to the predictive validity of childhood irritability, especially across developmental periods; similarly, little is known about explanatory factors underlying these predictions. This study had two goals: (1) to test the predictive validity of childhood irritability with respect to adolescent internalizing and externalizing problems, controlling for baseline ADHD and related psychopathology and (2) to test theoretically-derived family (i.e., parenting behavior, parenting stress) and social (i.e., peer status, social skills) constructs as explanatory factors of adolescent psychopathology. Two hundred thirty ethnically diverse (51.5% White) 5–10-year-old youth (32% female) with (n?=?121) and without (n?=?110) ADHD completed three separate laboratory-based assessments across six to seven years. Temporally-ordered predictors, putative mediators, and psychopathology outcomes were assessed using multiple informants (i.e., parent, teacher, youth) and methods (i.e., structured interviews, normed rating scales). Controlling for demographic factors, clinical correlates, and baseline psychopathology, childhood irritability uniquely predicted adolescent externalizing problems, but not internalizing problems. Next, analyses revealed that low social skills partially explained predictions of adolescent internalizing problems. However, family or social factors did not underlie predictions of adolescent externalizing problems. These preliminary findings support the predictive validity of childhood irritability with respect to early adolescent externalizing problems and implicate low social skills as a potentially unique mediator of internalizing outcomes. Intervention-induced improvements in social skills may minimize emergent psychopathology initiated by significant childhood irritability.