Biological basis of bipolar affective disorder

Abstract:

Bipolar affective disorder is severe psychiatric disorder caused by different biological and environmental factors whose interaction plays a crucial role in their development. Given a significant heterogeneity of the expression of symptoms, course and outcome, biological mechanisms implicated in these disorders are complex and relatively unclear. Although promising, the findings of regional brain abnormalities derived from structural, neurochemical and functional magnetic resonance studies are inconsistent and unspecific. Moreover, they indicate that bipolar disorders have similar pathophysiology to schizophrenia and unipolar depressive disorders. This hypothesis is also supported by findings of possibly genetically controlled neuropathological processes implicated in glial loss, synaptic function and synaptic plasticity, which appear to be similar in these disorders. In general, currently available evidence on the contribution of biological component to the etiopathogenesis of bipolar disorder does not support the hypothesis that mood disorders and schizophrenia are two completely separate diagnostic entities, nor that they are part of unitary continuum. Understanding the nature of disturbed neuronal function in bipolar disorder is important for the future improvement of diagnostic validity and the development of more effective therapeutic strategies. 

Key words:
bipolar disorder, biological factors, genetics, medical, neuroanatomy, neurophysiology