Acute episodes of predator exposure in conjunction with chronic social instability as an animal model of post-traumatic stress disorder

People who are exposed to horrific, life-threatening experiences are at risk for developing post-traumatic stress disorder (PTSD). Some of the symptoms of PTSD include persistent anxiety, exaggerated startle, cognitive impairments and increased sensitivity to yohimbine, an alpha(2)-adrenergic receptor antagonist. We have taken into account the conditions known to induce PTSD, as well as factors responsible for long-term maintenance of the disorder, to develop an animal model of PTSD. Adult male Sprague-Dawley rats were administered a total of 31 days of psychosocial stress, composed of acute and chronic components. The acute component was a 1-h stress session (immobilization during cat exposure), which occurred on Days 1 and 11. The chronic component was that on all 31 days the rats were given unstable housing conditions. We found that psychosocially stressed rats had reduced growth rate, reduced thymus weight, increased adrenal gland weight, increased anxiety, an exaggerated startle response, cognitive impairments, greater cardiovascular and corticosterone reactivity to an acute stressor and heightened responsivity to yohimbine. This work demonstrates the effectiveness of acute inescapable episodes of predator exposure administered in conjunction with daily social instability as an animal model of PTSD.     

The Psychosocial Vulnerability Model of Hostility as a Predictor of Coronary Heart Disease in Low-income African Americans

The current study examined social support and stress as mediators of the hostility—coronary heart disease (CHD) relationship as suggested by the psychosocial vulnerability model in a sample of low-income African Americans. Among 95 CHD patients and 30 healthy controls, hostility was negatively correlated with social support, but was not related to minor stress. CHD patients endorsed higher levels of hostility; however, the relationship between hostility and CHD status was diminished once stress and social support were included in the model. This study lends partial support for the psychosocial vulnerability model of hostility in African Americans, but suggests that the relationship between hostility and stress may be impacted by socioeconomic status.     

The importance of knowledge in vivid text memory: An individual-differences investigation of recollection and familiarity

The goal of this study was to examine how individual variation in readers’ skills and, in particular, their background knowledge about a text are related to text memory. Recollection and familiarity estimates were obtained from remember and know judgments to text ideas. Recollection estimates to old items were predicted by readers’ background knowledge, but not by other comprehension-related factors, such as word-decoding skill and working memory capacity. False alarms involving recollection of new items (inferences) were diminished as a function of verbal ability, working memory capacity, and reasoning but increased as a function of background knowledge. The results suggest that recollection indexes the reader’s ability to construct a text representation in which text ideas are integrated with relevant domain knowledge. Moreover, these results highlight the importance of background knowledge in explaining individual variation in comprehension and memory for text.     

Time travel through language: Temporal shifts rapidly decrease information accessibility during reading

The present study dissociated the immediate neural costs from the subsequent neural consequences of integrating time shifts into our mental representations of events. Event-related potentials were recorded as participants read scenarios that included words referring to short temporal shifts (e.g., after one second), moderate temporal shifts (e.g., after one hour), or long temporal shifts (e.g., after one year). These words were followed by repeated noun-phrase anaphors, which are preferred as referents for information no longer in attentional focus. The N400 was measured as an index of online conceptual integration. As the discourse unfolded, the N400 was larger for long- (e.g.,year) than for short- (e.g., second) shift words. For the anaphor, the N400 was modulated in the opposite direction. Thus, the introduction of a temporal discontinuity leads to immediate neural integration costs, as well as to decreased accessibility of earlier information.     

Effects of a Dependent Group-Oriented Contingency on Middle School Physical Education Students’ Fair Play Behaviors

This study investigated the effects of a dependent group-oriented contingency on the supportive and non-supportive fair play behaviors of 6th grade students engaged in volleyball games as part of their physical education instruction. Six students, one male and one female per class, from three classes, identified as demonstrating low incidences of supportive behaviors during volleyball games, were participants in this study. A multiple baseline across classes design was used to examine the data. During baseline few incidences of non-supportive behaviors occurred among all six students. However, the participants seldom displayed supportive behaviors during games (i.e., encouraged each other). Following the introduction of the dependent group contingency, supportive behaviors for all participants increased. Follow-up data, collected in an alternative setting, indicated variable maintenance. The results are discussed in the context of group contingencies and social behaviors in sports.     

Caregiver involvement in applied behavior-analytic research: A scoping review and discussion

We conducted a scoping review to characterize the role of caregiver involvement in behavior-analytic research. We reviewed eight behavioral-learning journals from 2011–2022 for works that included children or caregivers as participants and characterized caregiver involvement as passive (implications for caregivers, input, social validity) and active (implementation, caregiver behavior, training, caregiver-collected data). The review identified 228 studies, and almost all (96.1%; n = 219) involved caregivers in some capacity; 94.3% (n = 215) had passive involvement (26.8% had only passive involvement; n = 61), 69.3% (n = 158) had active involvement (1.8% had only active involvement; n = 4), and 3.9% (n = 9) had neither passive nor active involvement. Involvement generally increased over publication years. The most common types of involvement were implications for caregivers, implementation, and input; caregiver-collected data were rare. We propose considerations when engaging caregivers in research and suggest new avenues of inquiry related to caregivers' treatment objectives and social validity, treatment implementers, and caregiver-collected data.     

New Developments in Understanding Skilled Performance

ABSTRACT— Skilled performance, whether it involves rapid and accurate motor movements (such as playing a video game or using a scalpel in the operating room) or a high degree of domain knowledge (such as finding a small tumor in an X-ray or writing a journal article) typically involves learning and practice over an extended period of time. In light of recent theory and empirical research, I consider two enduring issues associated with skill acquisition: whether individuals become more alike in performance or more different over the course of skill acquisition, and what the determinants of individual differences in skilled performance are. Two broad classes of tasks are considered: tasks that involve speed and accuracy of motor movements and tasks that primarily involve domain knowledge. Issues of practice, ability, and other determinants of skilled performance such as gender and aging are discussed.     

A Case for Homogeneity of Personality at the Occupational Level

The forces of attraction–selection–attrition have been hypothesized to create homogeneity of personality within organizations, and vocational choice theory predicts that these forces lead to a ‘modal personality’ within given occupations. This study compared the homogeneity of a set of personality characteristics for 6582 incumbents from eight organizations in eight occupations. The results indicated that (1) the homogeneity hypothesis was supported both within organizations as well as within occupations; and (2) the homogeneity within occupations was higher than that found in organizations.