Sex Differences in Subclinical Psychotic Experiences: The Role of Daily-Life Social Interactions.

BACKGROUND AND HYPOTHESIS: Sex differences in psychosis are reported across the psychosis spectrum, including in subclinical stages. An important factor in understanding these variations is the subjective experience of everyday social interactions (SI). We investigated whether the presence of psychotic experiences (PEs), as well as associated distress, differs between men and women. We focused on the role of daily-life SI quality and whether its association with PEs varies by sex. STUDY DESIGN: We included adolescents from SIGMA, a general youth population study in Flanders, Belgium (n = 344; mean age = 18.7; 63.4% female). Psychotic experiences were measured using the PQ-16. We used Experience Sampling Methodology to assess daily-life SI. A multilevel model and multiple linear regressions were used to assess, respectively, the relationship between sex and SI quality and whether PEs and their association with SI quality differ between young men and women. STUDY RESULTS: The results of the multilevel linear regression model indicate that the prevalence of and distress associated with PEs were higher in women. No significant difference was observed in the subjective quality of daily SI. Social interaction quality was strongly related to PEs. This association did not seem to vary for the prevalence of PEs, though women's distress about PEs appeared to be more affected by SI quality. CONCLUSIONS: Present findings highlight the role of the subjective quality of SI in subclinical psychosis. More research is needed to investigate the mechanisms through which SI quality relates to PEs, and whether these differ between young men and women.

Social Company by a Receptive Mating Partner Facilitates Fear Extinction.

Fear extinction remains an unresolved challenge for behavioral exposure therapy in patients with post-traumatic stress disorder (PTSD). Previous reports have suggested that social support from either familiar or unfamiliar same-sex partners is beneficial to attenuating fear responses during fear extinction and renewal. Despite that, few studies have examined the effects of social support in advance on fear extinction and/or retrieval. It is also not clear whether social company by a receptive mating partner in advance facilitates fear extinction. In the present study, we address these questions by introducing a co-housing method, where fear-conditioned male mice are co-housed with or without a receptive mating partner prior to fear extinction. We found that while co-housing with an ovariectomized female mouse showed little effect on fear extinction or retrieval, social company by a receptive mating partner in advance dramatically facilitates fear extinction. In addition, the number of cFos-positive neurons in the basolateral amygdala (BLA) were also found to be reduced in male mice accompanied with receptive mating partner in response to fear extinction and retrieval, indicating diminished neuronal activation. Electrophysiological studies further showed that the excitability of excitatory neurons in BLA was decreased, which is probably due to the attenuated basal level of excitatory synaptic transmission. Together, our observations demonstrate an effect of social company by a receptive mating partner can facilitate fear extinction and afford a possible cellular mechanism.

Social Company Disrupts Fear Memory Renewal: Evidence From Two Rodent Studies.

Renewal of fear outside treatment context is a challenge for behavioral therapies. Prior studies suggest a social buffering effect that fear response is attenuated in the presence of social company. However, few studies have examined the role of social company in reducing fear renewal. Here, we used a Pavlovian fear conditioning procedure including acquisition, extinction and test stages to examine social buffering effect on fear memory renewal in male rats. The test context was manipulated to be either different from the extinction one in ABC model, or same as that in ACC model. All conditioned subjects underwent extinction individually in Experiment 1 but with a partner in Experiment 2. In test, both experiments manipulated social company (alone vs. accompanied) and context (ABC vs. ACC). Experiment 1 showed more freezing in ABC than in ACC model during the test-alone condition, indicating a fear renewal effect which, however, was absent during the test-accompanied condition. Also, accompanied subjects showed less freezing compared to alone subjects in the ABC model. In Experiment 2, animals showed a similar freezing in ABC and ACC models despite being tested alone, implying that social company offered at extinction disrupted fear renewal. Again, we observed reduced freezing in accompanied relative to alone subjects in the test. These results suggest that social company is effective in disrupting fear renewal after leaving treatment context.