Neurobiological findings in early phase schizophrenia

This paper summarises the available information on MRI-determined hippocamp al morphometry in first-episode patients as an illustration of the value an d interpretation of findings in the neurobiology of early phase schizophren ia. We report a thin slice (1.5 mm) study of 32 first episode and 39 high r isk patients which demonstrated significantly smaller hippocampi (right - 9 %, left - 11%) in first episode patients that were of a similar magnitude t o those found in chronic patients (right - 10%, left - 11%) but non-signifi cant volume reductions in high risk individuals, including the 15 subjects who subsequently developed psychoses. Consideration is given to the implica tions of these findings, including the possible role of early and later neu rodevelopmental influences. We present animal data showing that chronic pla cental insufficiency, as elicited by uterine artery ligation can give rise to substantial reduction (31%) in hippocampal volumes and reflect on other potentially relevant pathophysiological mechanisms, including those that ma y occur during the early phases of psychotic illnesses, including their pro dromes. Greater attention needs to be paid to the study of early phase psyc hosis in order to obtain a clearer understanding of the nature and time cou rse of neurobiological changes associated with it. Although there is a grow ing literature on first episode psychosis, there is a striking dearth of in formation on the neurobiology of the prodrome. (C) 2000 Elsevier Science, B .V. All rights reserved.