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The 3rd Schizophrenia International Research Society Conference was held in Florence, Italy, April 14-18, 2012 and this year had as its emphasis, "The Globalization of Research". Student travel awardees served as rapporteurs for each oral session and focused their summaries on the most significant findings that emerged and the discussions that followed. The following report is a composite of these summaries. We hope that it will provide an overview for those who were present, but could not participate in all sessions, and those who did not have the opportunity to attend, but who would be interested in an update on current investigations ongoing in the field of schizophrenia research., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Women have consistently demonstrated better verbal memory on tests that evaluate immediate and delayed free recall. In patients with schizophrenia, these verbal memory processes are relatively more preserved in women than men. However an understanding of the brain anatomy of the female advantage for verbal memory is still unclear. 29 females and 59 males with schizophrenia made comparable to 21 female and 27 male healthy volunteers were scanned using structural magnetic resonance imaging (sMRI) in order to assess volumes of regions across the entire brain. Sex differences within and between groups in the covariance structure of memory circuitry regions were evaluated using a novel approach to covariance analysis (the Box M Test). Brain areas of interest included the prefrontal cortex (PFC), inferior parietal lobule (iPAR), anterior cingulate gyrus (ACG), parahippocampus, and hippocampus (HIPP). Results showed significant differences in the covariance matrices of females and males with schizophrenia compared with their healthy counterparts, in particular the relationships between iPAR-PFC, iPAR-ACG, and HIPP-PFC. Sex differences in the iPAR-PFC relationship were significantly associated with sex differences in verbal memory performance. In control women, but not in men ACG volume correlated strongly with memory performance. In schizophrenia, ACG volume was reduced in females, but not in men, relative to controls. Findings suggest that the relationship between iPAR and PFC is particularly important for understanding the relative preservation of verbal memory processing in females with schizophrenia and may compensate for ACG volume reductions. These results illustrate the utility of a unique covariance structure modeling approach that yields important new knowledge for understanding the nature of schizophrenia., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Response to stress is dysregulated in psychosis (PSY). fMRI studies showed hyperactivity in hypothalamus (HYPO), hippocampus (HIPP), amygdala (AMYG), anterior cingulate (ACC), orbital and medial prefrontal (OFC; mPFC) cortices, with some studies reporting sex differences. We predicted abnormal steroid hormone levels in PSY would be associated with sex differences in hyperactivity in HYPO, AMYG, and HIPP, and hypoactivity in PFC and ACC, with more severe deficits in men. We studied 32 PSY cases (50.0% women) and 39 controls (43.6% women) using a novel visual stress challenge while collecting blood. PSY males showed BOLD hyperactivity across all hypothesized regions, including HYPO and ACC by FWE-correction. Females showed hyperactivity in HIPP and AMYG and hypoactivity in OFC and mPFC, the latter FWE-corrected. Interaction of group by sex was significant in mPFC (F = 7.00, p = 0.01), with PSY females exhibiting the lowest activity. Male hyperactivity in HYPO and ACC was significantly associated with hypercortisolemia post-stress challenge, and mPFC with low androgens. Steroid hormones and neural activity were dissociated in PSY women. Findings suggest disruptions in neural circuitry-hormone associations in response to stress are sex-dependent in psychosis, particularly in prefrontal cortex.