Corticosterone facilitates wbehavioral adaptation to a novel experience in a coordinate manner via mineralocorticoid (MR) and glucocorticoid receptors (GR). Initially, MR mediates corticosterone... Show moreCorticosterone facilitates wbehavioral adaptation to a novel experience in a coordinate manner via mineralocorticoid (MR) and glucocorticoid receptors (GR). Initially, MR mediates corticosterone action on appraisal processes, risk assessment and behavioral flexibility and then, GR activation promotes consolidation of the new information into memory. Here, we studied on the circular holeboard (CHB) the spatial performance of female mice with genetic deletion of MR from the forebrain (MRCaMKCre) and their wild type littermates (MRflox/flox mice) over the estrous cycle and in response to an acute stressor. The estrous cycle had no effect on the spatial performance of MRflox/flox mice and neither did the acute stressor. However, the MRCaMKCre mutants needed significantly more time to find the exit and made more hole visit errors than the MRflox/flox mice, especially when in proestrus and estrus. In addition, stressed MRCaMKCre mice in estrus had a shorter exit latency than the control estrus MRCaMKCre mice. About 70% of the female MRCaMKCre and MRflox/flox mice used a hippocampal (spatial, extra maze cues) rather than the caudate nucleus (stimulate-response, S-R, intra-maze cue) strategy and this preference did neither change over the estrous cycle nor after stress. However, stressed MRCaMKCre mice using the S-R strategy needed significantly more time to find the exit hole as compared to the spatial strategy using mice suggesting that the MR could be needed for the stress-induced strategy switch toward a spatial strategy. In conclusion, the results suggest that loss of MR interferes with performance of a spatial task especially when estrogen levels are high suggesting a strong interaction between stress and sex hormones. Show less
Background: High rates of psychopathology were found amongst deaf adolescents, but little is known about the psychosocial risk factors. This study investigated whether (1) less severe deafness and... Show moreBackground: High rates of psychopathology were found amongst deaf adolescents, but little is known about the psychosocial risk factors. This study investigated whether (1) less severe deafness and/or acquired or otherwise complicated deafness, and (2) having mainly contacts with hearing people, each represent chronic stressful conditions that moderate the associations between self-esteem and emotional problems. In addition, the moderating effect of observed peer rejection on the association between social acceptance and behavioural problems was explored. Method: Deaf adolescents of normal intelligence (N= 68) completed the Self Perception Profile for Adolescents. Psychopathology was assessed using a semi-structured interview with adolescents and reports by parents, teachers and expert ratings. Data on moderator variables were collected from school records, parental and teachers’ reports. Results: Emotional mental health problems were negatively associated with self-esteem and positivelywith peer rejection. The association between self-esteem and emotional problems was moderated by the deafness variable less severe deafness or acquired or otherwise complicated deafness. Behavioural mental health problems were positively associated with social acceptance and peer rejection but negatively with the amount of involvement with hearing people. Peer rejection moderated the association between social acceptance and behavioural problems. Conclusions: The findings emphasise the importance of considering se Show less
