Does neuroanatomy account for superior temporal dysfunction in early psychosis? A multimodal MRI investigation

Background: neuroimaging studies of ultra-high risk (uhr) and first-episode psychosis (fep) have revealed widespread alterations in brain structure and function. recent evidence suggests there is an intrinsic relationship between these 2 types of alterations; however,there is very little research linking these 2 modalities in the early stages of psychosis. methods: to test the hypothesis that functional alteration in uhr and fep participants would be associated with corresponding structural alteration,we examined brain function and structure in these participants as well as in a group of healthy controls using multimodal mri. the data were analyzed using statistical parametric mapping. results: we included 24 participants in the fep group,18 in the uhr group and 21 in the control group. patients in the fep group showed a reduction in functional activation in the left superior temporal gyrus relative to controls,and the uhr group showed intermediate values. the same region showed a corresponding reduction in grey matter volume in the fep group relative to controls. however,while the difference in grey matter volume remained significant after including functional activation as a covariate of no interest,the reduction in functional activation was no longer evident after including grey matter volume as a covariate of no interest. limitations: our sample size was relatively small. all participants in the fep group and 2 in the uhr group had received antipsychotic medication,which may have impacted neurofunction and/or neuroanatomy. conclusion: our results suggest that superior temporal dysfunction in early psychosis is accounted for by a corresponding alteration in grey matter volume. this finding has important implications for the interpretation of functional alteration in early psychosis. © 2015 8872147 canada inc.