Functional brain imaging in bipolar disorder

Abstract

Abstract Connectivity, as applied in neuroimaging research, is a statistical method of measuring relationships in neurofunctional activity. When comparing connectivity in participants with bipolar disorder to healthy individuals, the most consistent patterns of altered connectivity were localized in the salience network, central executive network, default mode network and sensory-motor cortex. Across bipolar mood states, researchers reported increased within–salience network connectivity and less efficient coupling between amygdala and ventrolateral prefrontal cortex compared to healthy participants. This evidence suggests overactive emotional and sensory processing combined with dysregulation of these brain regions by ventrolateral prefrontal cortex. There was also evidence of more widespread disconnect of prefrontal regions with salience and other central executive network regions in association with an acute affective bipolar state. Although the evidence was less consistent, we also discuss altered connectivity in association with the default mode network and sensory-motor cortex in individuals with bipolar disorder. Connectivity studies more fully represent the bipolar brain as an interconnected unit and characterize aberrant traits and state markers of the condition.