Structural brain abnormalities in bipolar disorder

Abstract

Abstract Bipolar disorder is a psychiatric condition associated with shifts in mood, energy, and activity levels severely altering the quality of life of affected individuals. Although widely accepted, the neurobiological bases of the disorder are still incompletely described. This chapter offers an in-depth description of the brain alterations characteristic of bipolar disorder from several perspectives; in the first part the chapter describes alterations of grey matter regions and volumetric differences of several neuronal networks and presents the alterations of key white matter bundles and demyelinization processes associated with bipolar disorder. In the second part the chapter describes current scientific findings about genetic vulnerabilities and presents specific brain differences associated with various clinical features (e.g., bipolar disorder subtype, length of illness, medication). To summarize, bipolar disorder is characterized by widespread reductions of grey matter volumes in the frontal gyrus, left anterior cingulate cortex, and right insula and alterations of white matter in the cingulate cortex, corpus callosum, and frontal regions.