Abstract
Increasing magnetic resonance imaging (MRI) studies in individuals with at‐risk mental state (ARMS) have shown brain morphologic changes prior to the onset of florid psychotic symptoms, which can be partly neurobiological predictors of future transition to psychotic disorders. However, the findings of single center ARMS studies were partly inconsistent with those of the earlier ARMS studies and could not necessarily detect brain morphologic difference between the ARMS individuals with and without later psychosis onset, possibly due to a small sample size in each study. We had then launched multicenter ARMS studies in Japan, which obtained MRI data from a relatively large sample at four sites (Toyama University, Toho University, Tohoku University, and Tokyo University) . Using this first Asian multicenter MRI dataset of ARMS individuals, we found several robust structural changes in the ARMS population. In particular, cortical thinning of the left anterior cingulate cortex and increased gyrification of the left occipital cortex were specific to the ARMS individuals who subsequently developed psychotic disorders. We have been also preparing an international multi‐site ARMS study using the Asian Consortium on MRI studies in Psychosis (ACMP) dataset, which is comparable in sample size to preceding large‐scale consortiums in Western countries. Due to the unique strengths of clinical research in Asia, we are expected to report novel and reliable results regarding brain changes in ARMS as well as possible clinical applicability of these neuroimaging research findings.
