Brain morphology in schizophrenia and bipolar disorder and the overlap

Abstract

With the development of MRI, brain volumes can be measured in vivo nowadays. MRI research on structure alterations in patients with schizophrenia led to new theories about the etiology of the disease. Reductions in brain volume were shown to be present in early stages of the disease, when most of the symptomatic change and loss of function also occur. What was regarded a neuro-degenerative disease, schizophrenia could be a consequence of a developmental malfunction as well. Next to schizophrenia, more insight can be gained on the nature of bipolar disorder. The overlap between these very heterogeneous mental disorders remains to be elucidated. This review summarizes studies which investigated structure alterations in schizophrenia and bipolar disorder with use of sMRI techniques, with the aim to gain information on the brain morphology of these illnesses. Furthermore, a possible relation of structure alterations with symptoms and functioning of patients is discussed. Current research so far point to main differences between schizophrenia and bipolar disorder. In schizophrenia, more pronounced reductions in brain volume are seen, which are likely to relate to symptoms and functioning of patients. More research, controlled for confounders like medication and subtype of disease is needed, however, to further establish the relevancy of structure alterations found. This is especially the case for research on bipolar disorder, which is scarce compared to research on schizophrenia.