The role of effective lever length in the perception of lifted weights

Objects are lifted through a system of body levers and, since the force required to lift objects decreases as the effective lever length is shortened, it was hypothesized that the perceived heaviness of objects would be less when they were lifted with the elbow bent than with it extended. Cans lifted from greater initial angles were consistently judged to be lighter by blindfolded Ss.     

The human operator as a single channel information system

A further experiment is reported on reaction times to stimuli separated by short intervals. On this occasion an auditory stimulus was followed by a visual stimulus. Results indicate that the pattern of delays at short intervals is the same as the pattern of delays when the stimuli are presented in one modality only. This suggests a model of the human operator functioning as a single channel through which information from both sense modalities has to pass before appropriate responses are organized. An attempt is also made to reconcile data with the known facts about the peripheral and central components of reaction time and the possibility that delays are the result of occupation of the channel for a central time plus a central refractory time is suggested.     

Entering Prostitution in Adolescence: History of Youth Homelessness Predicts Earlier Entry

The effect of youth homelessness on age of entry into prostitution was tested, controlling for other known covariates using a multivariate model. Women (N = 96) who self-identified as having engaged in prostitution completed cross-sectional standardized questionnaires (M_age = 42.6, SD = 9.18; 62% African American). Women with a history of youth homelessness entered prostitution nearly 8 years earlier than their peers without this history (at 18 vs. 25 years old). Lack of a high school degree or equivalent also predicted an earlier age of entry (at 20 vs. 28 years old). Findings highlight the poverty dynamics that underlie the relationship between early entry into prostitution and homelessness. Young women, living on the street or in shelters, with limited education and employment opportunities, are at high risk of entering prostitution when they are barely out of adolescence. Future research will be better able to design age-specific prevention strategies.     

The sexual dimorphic association of cardiorespiratory fitness to working memory in children

The present investigation examined the sexual dimorphic patterns of cardiorespiratory fitness to working memory in preadolescent children (age range: 7.7–10.9). Data were collected in three separate studies (Study 1: n = 97, 42 females; Study 2: n = 95, 45 females; Study 3: n = 84, 37 females). All participants completed a cardiorespiratory fitness assessment in addition to a specific measure of working memory (i.e. the operation span task, the n‐back task, or the Sternberg task). Results from all three samples revealed that higher cardiorespiratory fitness levels were associated with better working memory performance only for males with no such relation observed for females. In addition, the sexually dimorphic pattern was selective for the most challenging working memory conditions in each task. Together, these findings reveal new evidence that cardiorespiratory fitness is selectively related to better working memory performance for male children. This investigation provides additional insight into how interventions aimed at improving fitness may influence cognitive development differentially among preadolescent children.