Research into neural correlates of bipolar disorder has increased dramatically in the last few decades with advances in structural and functional neuroimaging. The data for structural differences are somewhat mixed, with a few studies showing no differences between individuals with bipolar disorder and healthy controls in prefrontal regions [76-78] and amygdala [79], and other studies reporting differences in both prefrontal regions [80-83] as well as amygdala [84-87]. Two recent meta-analyses using region of interest analyses found no evidence of gray matter abnormalities [88,89], but more recently one meta-analysis study using voxel based morphometry (VBM), which uses a whole brain technique, found reductions in grey matter in the rostral anterior cingulate cortex and the right fronto insular cortex [90], while another meta-analysis study, also using VBM, found reductions in grey matter in the anterior cingulate and insula [91].