In addition, each condition was also characterized by distinct abnormalities. Bipolar disorder was characterized by a reduction of coherence in several nodes within the DMN including the hippocampus, fusiform gyrus and pons, as well as abnormal recruitment of pontine, lateral parietal, and occipital regions into the DMN. Subjects with this condition also showed increased coherence of activity in the primary visual cortex in the V1 component analysis. Since participants were instructed to keep their eyes open during the scan, the V1 component was a particularly relevant control region. On the other hand, the schizophrenia group recruited a node in frontal polar cortex into the DMN, as well as multiple regions within the basal ganglia (caudate, putamen, globus pallidus) bilaterally. For bipolar disorder and schizophrenia, brain regions where DMN was more coherent than the control group were also more coherent than the other patient group (lateral parietal and visual cortices in bipolar disorder, and frontal polar cortex and basal ganglia in schizophrenia). Notable exceptions to this pattern included the insula which emerged in the Bipolar>Schizophrenia but not Bipolar>Control comparison, and temporal regions (fusiform and middle temporal gyri) and superior frontal gyrus which emerged in the Schizophrenia>Bipolar but not Schizophrenia>Control comparison.
