Is the medial amygdala part of the neural circuit modulating conditioned defeat in Syrian hamsters?

Conditioned defeat is a model wherein hamsters that have previously experienced a single social defeat subsequently exhibit heightened levels of avoidance and submission in response to a smaller, non-aggressive intruder. While we have previously demonstrated the critical involvement of the basolateral and central nuclei of the amygdala in the acquisition and expression of conditioned defeat, the role of the medial amygdala has yet to be investigated. In Experiment 1, muscimol, a GABA(A) receptor agonist, was infused bilaterally into the MeA prior to initial defeat training. Experiment 2 examined the effects of muscimol injections given prior to subsequent testing with a non-aggressive intruder. Finally, in Experiment 3, anisomycin was used to block protein synthesis in the medial and basolateral amygdala to examine the involvement of these nuclei in memory consolidation related to conditioned defeat. Submissive behavior was significantly reduced in animals that received muscimol prior to initial defeat training as well as in animals injected prior to testing with the non-aggressive intruder, indicating that the MeA is necessary for the acquisition and expression of conditioned defeat. In Experiment 3, however, anisomycin reduced conditioned defeat only when administered into the BLA, and not when injected into the MeA. The results of the present series of experiments suggest that, while the MeA may serve an important gateway for sensory information that is crucial for conditioned defeat, it does not appear to play a role in the plasticity including this behavioral response to social defeat.     

Special People? An Exploratory Study into Re-entering Missionaries’ Identity and Resilience

Home country re-entry from cross-cultural missionary work abroad may be associated with psychological distress. Re-entrants experience multiple losses including loss of identity which may be associated with personal/relational identity gaps and depersonalization/dehumanization. However, research suggests that some re-entrants are resilient with good mental health, while others are fragile with poor mental health. The aims of this paper are to explore the nature and frequency of re-entering missionaries’ identity gaps and their depersonalization/dehumanization in resilient and fragile re-entrants. Fifteen re-entering adult Australian cross-cultural missionary workers from four interdenominational Australian mission organizations completed semi-structured interviews. Results were analysed using modified Consensual Qualitative Research methods. Links were established between personal/relational identity gaps, depersonalization/dehumanization and resilience on re-entry. Implications for re-entrants’ care are discussed with suggestions for further research.     

A comparison of retrospective self-report versus ecological momentary assessment measures of affective lability in the examination of its relationship with bulimic symptomatology

Affective lability has been linked to several maladaptive behaviors ( [Anestis et?al., 2009] and [Coccaro, 1991]). Methodology for measuring affective lability varies and includes retrospective self-report and ecological momentary assessment (EMA). In this study, we sought to test these methodologies by examining which better predicted binge eating episodes and general eating disorder symptoms in a sample (n = 131) of women diagnosed with bulimia nervosa (BN). We hypothesized that, while the two forms of measurement would be correlated with one another and predict binge eating episodes, EMA affective lability would be the stronger predictor. Results supported several hypotheses. Specifically, both EMA affective lability and retrospective self-report affective lability significantly predicted global eating disorder symptoms, even when controlling for depression, age, body mass index, and level of education, EMA affective lability exhibited a significantly stronger correlation with binge eating episodes than did retrospective self-report affective lability, and EMA affective lability predicted number of binge eating episodes on any given day controlling for the same list of covariates. Limitations include the use of a clinical sample that may limit the generalizability of our findings. Findings highlight the importance of affect in such behavior.     

The Animal = Male Hypothesis: Children's and Adults' Beliefs About the Sex of Non–Sex-Specific Stuffed Animals

The Animal = Male Hypothesis, a variation of Silveira's People = Male Hypothesis (Silveira, 1980), was examined. In Study 1, children ages 3–10 years and adults told stories about a gender-neutral stuffed animal, in Study 2 children ages 5–6 years told stories about 3 neutral and 3 feminine animals, and in Study 3 children ages 5–7 years told stories about 2 neutral animals, observed an adult model use feminine pronouns to refer to an animal, then told stories about 2 more animals. Dependent variables were the pronouns participants used to refer to the animals and what sex they believed the animals were. Results showed strong evidence for an animal = male bias in all 3 studies among children and adults of both sexes on both dependent measures. There were few sex-related differences. The modeling intervention was not successful in reducing the bias.     

Bullying and victimization among black and Hispanic adolescents

The prevalence of bullying and victimization by gender, grade level, and race/ethnicity was examined among a sample of low socioeconomic, Black and Hispanic 6th- to 12th-graders in a large urban school district in Texas. Bullying and victimization were measured using specific behaviors. Students were classified as bullies (7%), victims (12%), bully-victims (5%), or neither (76%), depending on the number and frequency of reported experiences. For specific types of bullying (e.g., spreading rumors, excluding others), 4.5%-9.4% of students reported participation. Specific types of victimization (e.g., being hit or pushed, picked on) ranged from 6%-12%. Gender differences were not observed for general bullying and victimization, but physical and some verbal types were more prevalent among males. Blacks were more likely to participate in bullying and victimization, and these experiences seemed to peak in the 9th grade. This study adds to the literature as few U.S. studies on both general and specific types of bullying have been conducted among low socioeconomic, racial/ethnic minority students in middle and high school.     

On the role of covarying functions in stimulus class formation and transfer of function

This experiment investigated whether directly trained covarying functions are necessary for stimulus class formation and transfer of function in humans. Initial class training was designed to establish two respondent-based stimulus classes by pairing two visual stimuli with shock and two other visual stimuli with no shock. Next, two operant discrimination functions were trained to one stimulus of each putative class. The no-shock group received the same training and testing in all phases, except no stimuli were ever paired with shock. The data indicated that skin conductance response conditioning did not occur for the shock groups or for the no-shock group. Tests showed transfer of the established discriminative functions, however, only for the shock groups, indicating the formation of two stimulus classes only for those participants who received respondent class training. The results suggest that transfer of function does not depend on first covarying the stimulus class functions.     

The impact of a history of sexual abuse on high-risk sexual behaviors among females attending alternative schools

The goal of this study was to explore whether a history of sexual abuse is associated with high-risk sexual behaviors among female adolescents attending alternative schools in a large urban city in the southwestern United States, and to examine the role of depression and substance abuse in explaining this association. One hundred eighty-four sexually active female adolescents constituted the sample for this analysis. Forty-nine (26.6%) reported that they were forced to have sex. Having a history of sexual abuse substantially increased sexual risk behaviors. Adolescents reporting a history of sexual abuse, compared to those who did not report such a history, were significantly more likely to have initiated sexual activity (intercourse) before age 14, to have had three or more sexual partners in the last 3 months, and to have had a history of sexually transmitted diseases. These associations remained significant after controlling for age, ethnicity, and family income. Depression and substance abuse did not explain the association between sexual abuse and high-risk sexual behaviors. It seems reasonable to conclude that adolescents with a history of sexual abuse have greater difficulty practicing safe sexual behaviors than do those who have not been sexually abused. Given the prevalence of child sexual abuse and the extent of its impact, it is critical that intervention strategies for adolescent females address the issue of abuse and help them adopt self-protective sexual behaviors. The findings also highlight the importance of targeting adolescents who attend alternative schools.