Altered affective, executive and sensorimotor resting state networks in patients with pediatric mania

Pediatric bipolar disorder (PBD) is a cyclical illness with episodes of mania and depression complicated by neurocognitive dysfunction. Mania is characterized by symptoms such as grandiosity, decreased need for sleep, flight of ideas, distractibility, increased goal-directed activity and excessive risk-taking. Low-frequency (0.01–0.1 Hz) blood oxygen level–dependent (BOLD) signals at rest have been hypothesized to reveal the brain’s intrinsic neural activity that could be abnormal during an episode of mania. Synchronized brain circuitries at rest have been consistently identified; they reflect underlying monosynaptically or polysynaptically interconnected anatomic regions and may be influenced by hist ory of coactivation during active behaviour. Given the structural abnormalities and the taskinvoked functional activation abnormalities observed in children with bipolar disorder, it is plausible that the topography of the resting state networks (RSNs) may also be abnormal in these children. While the association between resting state activation and task-based functional activation is uncertain, elucidating the integrity of RSNs in children with bipolar disorder may shed light on functional abnormalities and lead to better understanding of intervention targets in pediatric mania. Abnormal structural findings in children with bipolar dis order include decreased volume in the anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC) and amygdala, and increased volume in the basal ganglia.