Neuroimaging and neuropsychological assessment in bipolar disorder

The detrimental psychosocial effects of bipolar disorders have long been known, with studies indicating impairments among diagnosed individuals across a number of life domains, including marital, occupational, and educational functioning. Increased rates of medical comorbidities also routinely have been reported among persons with bipolar disorders. It is only relatively recently, however, that investigations have begun evaluating more thoroughly the neurological correlates of bipolar disorders and the manner in which these variables may influence treatment and outcome. A multitude of empirical investigations now suggests that, relative to healthy controls, individuals with bipolar disorders not only perform more poorly across formal measures of neurocognition, in particular tests of executive functioning, but also demonstrate both structural and functional disparities on various neuroimaging studies. Furthermore, it now appears that these differential patterns of cerebral abnormalities may be associated with outcome. Research also has suggested that the mood state of individuals with bipolar disorders may be differentiated by lateralization of activation in particular brain regions. This chapter will provide a comprehensive review of the literature as it pertains to findings of investigations that have examined the neurocognitive sequelae of bipolar disorders via structural and functional magnetic resonance imaging and objective neuropsychological assessment.