Bipolaroids: functional imaging in bipolar disorder.

OBJECTIVE: To evaluate the literature pertaining to the use of functional magnetic resonance imaging (fMRI) in bipolar disorder research. METHOD: A search for papers published in English in journals from 1984 onwards was conducted using MedLine and EMBASE with the following terms: functional neuroimaging or fMRI and depression or bipolar disorder. In addition, retrieved papers and literature known to the authors was also scrutinized for further relevant reports. RESULTS: The research findings from 26 articles are tabulated and the results from 10 articles dealing specifically with bipolar disorder are discussed in detail. CONCLUSION: fMRI is a useful tool for investigating bipolar disorder. Preliminary studies point to trait and state abnormalities involving structures known to be associated with the generation and modulation of emotion. The patterns of fMRI activation are different to those found in healthy subjects and patients with major depression. FMRI studies are likely to provide valuable insights into the pathophysiology of bipolar disorder.