Neurosteroids in the Hippocampus: Neuronal Plasticity and Memory

The hippocampus, which is critically involved in learning and memory processes, is known to be a target for the neuromodulatory actions of steroid hormones produced by the adrenal glands and gonads. Much of the work of B.S. McEwen and collaborators has focused on the role of glucocorticosteroids and estrogen in modulating hippocampal plasticity and functions. In addition to hormones derived from the endocrine glands, cells in the hippocampus may be exposed to locally synthesized neurosteroids, including pregnenolone, dehydroepiandrosterone and their sulfated esters as well as progesterone and its reduced metabolites. In contrast to hormones derived from the circulation, neurosteroids have paracrine and/or autocrine activities. In the hippocampus, they have been shown to have trophic effects on neurons and glial cells and to modulate the activity of a variety of neurotransmitter receptors and ion channels, including type A gamma-aminobutyric acid, N-methyl-D-aspartate and sigma receptors and N- and L-type Ca2+ channels. There is accumulating evidence that some neurosteroids, in particular pregnenolone sulfate, have strong influences on learning and memory processes, most likely by regulating neurotransmission in the hippocampus. However, the hippocampus is not the only target for the mnesic effects of neurosteroids. Associated brain regions, the basal nuclei of the forebrain and the amygdaloid complex, are also involved. Some neurosteroids may thus be beneficial for treating age- or disease-related cognitive impairments.     

Does understanding relational terminology mediate effects of intervention on compare word problems?

The purpose of this study was to assess whether understanding relational terminology (i.e., more, less, and fewer) mediates the effects of intervention on compare word problems. Second-grade classrooms (N=31) were randomly assigned to one of three conditions: researcher-designed word-problem intervention, researcher-designed calculation intervention, or business-as-usual (teacher-designed) control. Students in word-problem intervention classrooms received instruction on the compare problem type, which included a focus on understanding relational terminology within compare word problems. Analyses, which accounted for variance associated with classroom clustering, indicated that (a) compared with the calculation intervention and business-as-usual conditions, word-problem intervention significantly increased performance on all three subtypes of compare problems and on understanding relational terminology, and (b) the intervention effect was fully mediated by students' understanding of relational terminology for one subtype of compare problems and partially mediated by students' understanding of relational terminology for the other two subtypes.     

Same‐ and Other‐Sex Victimization: Are the Risk Factors Similar?

Risk factors for same‐ and other‐sex victimization were examined in a longitudinal data set involving 9‐ to 14‐year‐old students. The findings regarding same‐sex victimization supported the view that bullies select personally and interpersonally vulnerable targets in order to maximize their gains in status while minimizing loss of affection within their same‐sex peer group. Although low self‐esteem was a joint predictor of same‐ and other‐sex victimization, rejection and lack of friends among other‐sex peers failed to predict victimization by other‐sex bullies, and being perceived as popular among other‐sex peers increased the risk. Although the findings suggests that interpersonal risk factors for other‐sex victimization differ from those found for same‐sex victimization, they do not provide strong support for heterosexual interest being the basis for other‐sex target selection, as suggested by some previous literature. As about half of the study participants were involved in the KiVa antibullying program, we had the possibility to examine whether the program effects were similar for same‐ and other‐sex victimization. It turned out that in middle schools the program decreased only same‐sex victimization, whereas in elementary school the decrease was observed regardless of the sex composition of bully–victim dyads. Aggr. Behav. 38:442‐455, 2012. © 2012 Wiley Periodicals, Inc.     

Therapist effects and the dissemination of cognitive behavior therapy for chronic fatigue syndrome in community-based mental health care

ObjectiveThe purpose of the present study was to explore the role of the therapist in the dissemination of manualized cognitive behavior therapy (CBT) for chronic fatigue syndrome (CFS) outside specialized treatment settings.MethodWe used the routinely collected outcome data of three community-based mental health care centers (MHCs) which implemented and sustained CBT for CFS during the course of the study. Ten therapists, who all received the same training in CBT for CFS, and 103 patients with CFS were included.ResultsRandom effects modeling revealed a significant difference in mean post-treatment fatigue between therapists. The effect of the therapist accounted for 21% of the total variance in post-treatment fatigue in our sample. This effect could be explained by the therapists’ attitude toward working with evidence-based treatment manuals as well as by the MHC where CBT for CFS was delivered.ConclusionThe context in which CBT for CFS is delivered may play an important role in the accomplishment of established therapy effects outside specialized treatment settings. Due to the small sample size of MHCs and the different implementation scenarios in which they were engaged, our findings should be interpreted as preliminary results which are in need for replication.     

Who victimizes whom and who defends whom? A multivariate social network analysis of victimization,aggression, and defending in early childhood

The aim of this research was to investigate the interplay between victim‐aggressor relationships and defending relationships in early childhood to test the proposition that young aggressors are less selective than older children in their choice of vulnerable targets. Cross‐sectional multivariate statistical social network analyses (Exponential Random Graph Models) for a sample of 177 preschoolers from seven classes, 5‐ to 7‐years‐old, revealed that boys were more aggressive than girls, toward both boys and girls, whereas defending relationships were most often same‐sex. There was significant reciprocity in aggression, indicating that it was more often bidirectional rather than unidirectional. In addition, aggressors clearly defended each other when they shared their targets of aggression, whereas a marginally significant trend appeared for defending between victims who were victimized by the same aggressors. Furthermore, teacher‐rated dominance was positively associated with children's involvement in both aggression and victimization, and teacher‐rated insecurity was associated with less aggression, but not with victimization. These findings suggest that those who are reported as being victimized may retaliate, or be aggressive themselves, and do not display some of the vulnerabilities reported among older groups of victims. The findings are in line with the proposition that young aggressors are less strategic than older children in targeting vulnerable victims. The network approach to peer victimization and defending contributes to understanding the social processes facilitating the development of aggression in early childhood.     

Sleep disturbance and emotion dysregulation as transdiagnostic processes in a comorbid sample

Sleep disturbance and emotion dysregulation have been identified as etiologic and maintaining factors for a range of psychopathology and separate literatures support their relationships to anxiety, depression, PTSD, and alcohol dependence (AD) symptom severity. Previous studies have examined these relationships in isolation, failing to account for the high rates of comorbidity among disorders. It is not yet known whether these processes uniquely predict symptom severity in each of these domains. Participants were 220 patients in residential substance abuse treatment, who had experienced a potentially traumatic event and exceeded screening cutoffs for probable PTSD and problematic alcohol use. Controlling for emotion dysregulation and the interrelationships among the outcome variables, insomnia was uniquely associated with anxiety (B = .27, p < .001), depression (B = .25, p < .001), PTSD (B = .22, p < .001), and AD (B = .17, p = .01) symptom severity. Similarly, controlling for insomnia, emotion dysregulation was uniquely associated with anxiety (B = .40, p < .001), depression (B = .47, p < .001), PTSD (B = .38, p < .001), and AD (B = .26, p < .001) symptom severity. Insomnia and emotion dysregulation appear to be transdiagnostic processes uniquely associated with symptom severity across a number of different domains and might be important treatment targets for individuals with PTSD and AD.