Methylphenidate enhances extinction of contextual fear

Methylphenidate (MPH, Ritalin) is a norepinephrine and dopamine transporter blocker that is widely used in humans for treatment of attention deficit disorder and narcolepsy. Although there is some evidence that targeted microinjections of MPH may enhance fear acquisition, little is known about the effect of MPH on fear extinction. Here, we show that MPH, administered before or immediately following extinction of contextual fear, will enhance extinction retention in C57BL/6 mice. Animals that received MPH (2.5-10 mg/kg) before an extinction session showed decreased freezing response during extinction, and the effect of the 10 mg/kg dose on freezing persisted to the next day. When MPH (2.5-40 mg/kg) was administered immediately following an extinction session, mice that received MPH showed dose-dependent decreases in freezing during subsequent tests. MPH administered immediately after a 3-min extinction session or 4 h following the first extinction session did not cause significant differences in freezing. Together, these findings demonstrate that MPH can enhance extinction of fear and that this effect is sensitive to dose, time of injection, and duration of the extinction session. Because MPH is widely used in clinical treatments, these experiments suggest that the drug could be used in combination with behavioral therapies for patients with fear disorders.     

Evaluation is a Dynamic Process: Moving Beyond Dual System Models

Over the past few decades, dual attitude/process/system models have emerged as the dominant framework for understanding a wide range of psychological phenomena. Most of these models characterize the unconscious and conscious mind as being built from discrete processes or systems: one that is reflexive, automatic, fast, affective, associative, and primitive, and a second that is deliberative, controlled, slow, cognitive, propositional, and more uniquely human. Although these models serve as a useful heuristic for characterizing the human mind, recent developments in social and cognitive neuroscience suggest that the human evaluative system, like most of cognition, is widely distributed and highly dynamic. Integrating these advances with current attitude theories, we review how the recently proposed Iterative Reprocessing Model can account for apparent dual systems as well as discrepancies between traditional dual system models and recent research revealing the dynamic nature of evaluation. Furthermore, we describe important implications this dynamical system approach has for various social psychological domains.     

Productive and Re‐productive Thinking in Solving Insight Problems

Many innovations in organizations result when people discover insightful solutions to problems. Insightful problem‐solving was considered by Gestalt psychologists to be associated with productive, as opposed to re‐productive, thinking. Productive thinking is characterized by shifts in perspective which allow the problem solver to consider new, sometimes transformational, approaches. Re‐productive thinking, on the other hand, involves the application of familiar, routine, procedures. This article reports a study which investigated how self‐reported productive and re‐productive thinking are related to an individual's ability to solve insight problems. Our measures were tested against the Kirton Adaption‐Innovation Inventory (KAI), and a battery of spatial insight problems. The results indicated that productive and re‐productive thinking and the KAI were successful in predicting performance on spatial insight problems. Furthermore, the measures of productive and re‐productive thinking accounted for spatial insight performance independently of scores on the KAI. In addition, the results suggested that re‐productive thinking consists of two different components—one based on group conventions and the other on personal experience. Each contributed differently to solving insight problems.     

Interpersonal Mistreatment of Women in the Workplace

The purpose of this paper is to introduce the work included in the special issue: Interpersonal Mistreatment of Women in the Workplace. In doing so, the authors develop a multilevel conceptual model, illustrating how the research included in the special issue address causes and consequences of interpersonal mistreatment at the micro, meso, and macro-level of analysis. In addition, the integrated model demonstrates how factors at different levels both influence and are influenced by those at other levels of analysis. Based on this collective work, the authors encourage researchers interested in addressing the mistreatment and marginalization of less powerful groups to consider the multilevel causes and consequences of such behavior. It is only through holistic examinations that researchers can we fully understand this insidious problem and encourage people—whether likely targets of mistreatment or not—to take a stand to end this treatment in workplaces and other society as a whole.     

Implicit chaining in cotton-top tamarins (Saguinus oedipus) with elements equated for probability of reinforcement

Three experiments examined the implicit learning of sequences under conditions in which the elements comprising a sequence were equated in terms of reinforcement probability. In Experiment 1 cotton-top tamarins (Saguinus oedipus) experienced a five-element sequence displayed serially on a touch screen in which reinforcement probability was equated across elements at .16 per element. Tamarins demonstrated learning of this sequence with higher latencies during a random test as compared to baseline sequence training. In Experiments 2 and 3, manipulations of the procedure used in the first experiment were undertaken to rule out a confound owing to the fact that the elements in Experiment 1 bore different temporal relations to the intertrial interval (ITI), an inhibitory period. The results of Experiments 2 and 3 indicated that the implicit learning observed in Experiment 1 was not due to temporal proximity between some elements and the inhibitory ITI. The results taken together support two conclusion: First that tamarins engaged in sequence learning whether or not there was contingent reinforcement for learning the sequence, and second that this learning was not due to subtle differences in associative strength between the elements of the sequence.     

Alcohol Availability and Violence among Inner-City Adolescents: A Multi-Level Analysis of the Role of Alcohol Outlet Density

Researchers recognize that the connection between alcohol and peer violence may relate to community level ecological factors, such as the location of businesses that sell alcohol. Building on previous research among adults, this study examines the relationship between alcohol outlet density and violent behaviors among adolescents, taking into account demographic characteristics, individual alcohol use, and neighborhood level socioeconomic indicators. Data drawn from a diverse Emergency Department based sample of 1,050 urban adolescents, combined with tract level data from the state liquor control commission and U.S. Census, were analyzed. Results of multivariate multi-level regression analysis indicate that alcohol outlet density is significantly related to adolescents’ violent behaviors, controlling for demographic characteristics and individual alcohol use. Census tract level socioeconomic indicators were not significantly associated with youth violence. Findings suggest that alcohol outlet density regulation should be considered as part of broader violence prevention strategies for urban adolescents.     

The relationship between self‐perception of physical attractiveness and sexual bullying in early adolescence

The relationship between self‐perception of physical attractiveness and four measures of sexual bullying behavior (victimization, perpetration, having friends who sexually bully, and observation of sexual bullying among peers at school) was examined in a sample of 396 middle school age students. Students who perceived themselves to be more physically attractive than their peers reported sexually bullying others more, being sexually bullied by others more, observing more sexual bullying, and having more friends who sexually bully others than did students who perceived themselves as average looking. In addition, males who perceived themselves to be less physically attractive than their peers reported being victimized more and reported observing more sexual bullying in the school environment. These findings highlight the importance of physical attractiveness in the early initiation of sexual harassment. Implications for future research and interventions with early adolescents are discussed. Aggr. Behav. 36:271–281, 2010. © 2010 Wiley‐Liss, Inc.