Persistence and relapse of reinforced behavioral variability

The present study examined persistence and relapse of reinforced behavioral variability in pigeons. Pigeons emitted four‐response sequences across two keys. Sequences produced food according to a lag schedule, in which a response sequence was followed by food if it differed from a certain number of previous sequences. In Experiment 1, food was delivered for sequences that satisfied a lag schedule in both components of a multiple schedule. When reinforcement was removed for one component (i.e., extinction), levels of behavioral variability decreased for only that component. In Experiment 2, food was delivered for sequences satisfying a lag schedule in one component of a multiple schedule. In the other component, food was delivered at the same rate, but without the lag variability requirement (i.e., yoked). Following extinction, levels of behavioral variability returned to baseline for both components after response‐independent food delivery (i.e., reinstatement). In Experiment 3, one group of pigeons responded on a lag variability schedule, and the other group responded on a lag repetition schedule. For both groups, levels of behavioral variability increased when alternative reinforcement was suspended (i.e., resurgence). In each experiment, we observed some evidence for extinction‐induced response variability and for variability as an operant dimension of behavior.     

Early Adolescent Growth in Depression and Conduct Problem Symptoms as Predictors of Later Substance Use Impairment

Most studies of adolescent substance use and psychological comorbidity have examined the contributions of conduct problems and depressive symptoms measured only at particular points-in-time. Yet, during adolescence, risk factors such as conduct problems and depression exist within a developmental context, and vary over time. Though internalizing and comorbid pathways to substance use have been theorized (Hussong et al. Psychology of Addictive Behaviors 25:390-404, 2011), the degree to which developmental increases in depressive symptoms and conduct problems elevate risk for substance use impairment among adolescents, in either an additive or potentially a synergistic fashion, is unclear. Using a school-based sample of 521 adolescents, we tested additive and synergistic influences of changes in depressive symptoms and conduct problems from 6th to 9th grade using parallel process growth curve modeling with latent interactions in the prediction of late adolescent (12th grade) substance use impairment, while examining gender as a moderator. We found that the interaction between growth in depression and conduct disorder symptoms uniquely predicted later substance use problems, in addition to main effects of each, across boys and girls. Results indicated that adolescents whose parents reported increases in both depression and conduct disorder symptoms from 6th to 9th grade reported the most substance use-related impairment in 12th grade. The current study demonstrates that patterns of depression and conduct problems (e.g., growth vs. decreasing) are likely more important than the static levels at any particular point-in-time in relation to substance use risk.     

Psychopathic traits and men’s anger response to interpersonal conflict: A pilot study

Psychopathy is associated with emotional dysfunction that impedes the experience of emotions such as fear and sadness and has been purported to facilitate violent behavior. However, findings relative to the association between psychopathy and anger have not been reliably substantiated. Theorists have proposed that psychopathy predisposes one to experience greater frustration and anger, whereas other experts have suggested that there is no convincing evidence for this assertion. In the present study, we tested the relationship between psychopathy subfactors and anger subsequent to conflict or non-conflict interactions. Sixty-eight collegiate-men completed the Self-Report Psychopathy Scale and read vignettes depicting either a conflict or non-conflict scenario and were asked to imagine themselves in the situation. Following presentation of the vignettes, participants completed a lexical-decision-task assessing affective states. Results indicated that the psychopathy subfactors demonstrated strong differential associations, where Factor 1 showed negative and Factor 2 showed positive association with anger activation in response to interpersonal conflict. Findings are discussed in terms of the importance of anger as a facilitator of violence in some psychopathic individuals.     

Negative valence can evoke a liberal response bias in syllogistic reasoning

Recently, studies have demonstrated that negative valence reduces the magnitude of the belief-bias effect in syllogistic reasoning. This effect has been localized in the reasoning stage, in the form of increased deliberation on trials where validity and conclusion believability are incongruent. Here, using signal detection theory, we show that the attenuation of belief bias observed when valence was negative can also be evoked by a liberal response bias at the decision stage. Indeed, when valence was negative participants adopted a more liberal criterion for judging syllogisms as “valid,” and were overconfident in their judgments. They also displayed less sensitivity in distinguishing between valid and invalid syllogisms. Our findings dovetail with recent evidence from memory research suggesting that negative valence can evoke a liberal response bias without improving performance. Our novel contribution is the demonstration that the attenuating effect of negative valence on belief bias can take multiples routes—by influencing the decision stage as was the case here, the reasoning stage as has been demonstrated elsewhere, and potentially both stages.     

A Prospective Longitudinal Study of Shyness from Infancy to Adolescence: Stability, Age-Related Changes, and Prediction of Socio-Emotional Functioning

This longitudinal, population-based and prospective study investigated the stability, age-related changes, and socio-emotional outcomes of shyness from infancy to early adolescence. A sample of 921 children was followed from ages 1.5 to 12.5?years. Parent-reported shyness was assessed at five time points and maternal- and self-reported social skills and symptoms of anxiety and depression were assessed at age 12.5?years. Piecewise latent growth curve analysis was applied, with outcomes regressed on latent shyness intercept and slope factors. Results showed moderate stability and increasing levels of shyness across time, with more variance and a steeper increase in early as compared to mid-to-late childhood. Both stable shyness and increased shyness in mid-to-late (but not early) childhood predicted poorer social skills and higher levels of anxiety and depression symptoms in early adolescence. The implications of the evidence for two developmental periods in shyness trajectories with differential impact on later socio-emotional functioning are discussed.     

Written exposure as an intervention for PTSD: A randomized clinical trial with motor vehicle accident survivors

The present study examined the efficacy of a brief, written exposure therapy (WET) for posttraumatic stress disorder (PTSD). Participants were 46 adults with a current primary diagnosis of motor vehicle accident-related PTSD. Participants were randomly assigned to either WET or a waitlist (WL) condition. Independent assessments took place at baseline and 6-, 18-, and 30-weeks post baseline (WL condition not assessed at 30 weeks). Participants assigned to WET showed significant reductions in PTSD symptom severity at 6- and 18-week post-baseline, relative to WL participants, with large between-group effect sizes. In addition, significantly fewer WET participants met diagnostic criteria for PTSD at both the 6- and 18-week post-baseline assessments, relative to WL participants. Treatment gains were maintained for the WET participants at the 30-week post baseline assessment. Notably, only 9% of participants dropped out of WET and the WET participants reported a high degree of satisfaction with the treatment. These findings suggest that a brief, written exposure treatment may efficaciously treat PTSD. Future research should examine whether WET is efficacious with other PTSD samples, as well as compare the efficacy of WET with that of evidence-based treatments for PTSD.     

Remembering more than meets the eye: A study of memory confusions about incomplete visual information

The purpose of this series of four experiments was to examine the possible role of spontaneous imagery in memory confusions about the way in which visual information had been experienced. After viewing pictures of familiar objects, complete or incomplete in visual form, participants were asked to remember the way in which the objects had been presented. Although, as predicted, memory for the objects themselves was quite good, participants falsely remembered seeing complete versions of pictures that were actually presented as incomplete. These false reports were observed across a variety of encoding and testing conditions. The results suggest that the false reports (referred to here as completion errors) are due to internal representations based on filling-in processes in response to the encoding of incomplete visual information. As such, the results also speak to alternative explanations for the completion errors and, more broadly, to theoretical perspectives that draw on filling-in processes when accounting for object identification and object memory.     

Reproduction of End-Location and Distance of Movement in Early and Later Blinded Subjects

This study examined the ability of early and later blinded subjects to reproduce the end location and distance of preselected arm movements of two different amplitudes (approximately 30 degrees and approximately 60 degrees). Both groups were found to reproduce end location with greater accuracy and less variability than distance. The early blinded subjects were less accurate however and more variable in their reproductions of both movement cues than the later blinded subjects. The complications of these findings for the role of visual representation in memory for movement are discussed.     

Self‐esteem,perception of relationships,and emotional distress: A cross‐cultural study

This study examined the relative importance of self‐esteem, family cohesion, and support from friends in predicting depressed mood and anxiety in Japanese and American college students. Contrary to expectations, self‐esteem was the strongest predictor of emotional distress in both groups of students. Nevertheless, consistent with predictions derived from Markus and Kitayama's theory of self‐construals, family cohesion accounted for a significantly larger percentage of the variance in predicting emotional distress in Japan than in the United States. In both countries, the relations between support from friends and the measures of emotional distress were entirely mediated by self‐esteem. However, among Japanese students, family cohesion accounted for additional significant variance in predicting the measures of emotional distress, even after controlling for self‐esteem.