Inside The Bipolar Brain

By Sora Song

VENTRAL STRIATUM

WHAT IT DOES: Helps the brain process rewards

WHAT HAS GONE WRONG: Studies show overactivity and a 30% loss in gray matter in this region, causing people to lose judgment about how certain behaviors, such as overspending or being sexually indiscriminate, will affect their lives

PREFRONTAL CORTEX

WHAT IT DOES: Parts of the prefrontal cortex regulate emotion and are instrumental in processing rewards and motivation

WHAT HAS GONE WRONG: Studies show a 20% to 40% reduction in gray matter-the result of a loss of the branches that connect neurons

AMYGDALA

WHAT IT DOES: One of the brain's emotional centers; helps in the recognition of facial expressions and tones of voice. Neural transmissions increase in response to emotional stimuli. Normally, repeated exposure to the same experiences or images leads to habituation, or reduced response

WHAT HAS GONE WRONG: Habituates slowly to some stimuli, remaining reactive beyond the usual response time

HIPPOCAMPUS

WHAT IT DOES: One of the brain's memory centers. One layer of the hippocampus, the subiculum, helps recognize contexts that represent danger or reward

WHAT HAS GONE WRONG: Loss of branches that connect neurons may lead to a constant state of anxiety because the person can no longer identify safe situations

BRAIN STEM

WHAT IT DOES: The raphe nucleus in the brain stem is home to serotonin cell bodies, which create and disperse the neurotransmitter to different parts of the brain

WHAT HAS GONE WRONG: Bipolar patients have a 40% loss of the serotonin 1a receptor in the raphe, which may contribute to atrophy of neurons and depression

SOURCE: Wayne Drevets, M.D., National Institute of Mental Health

Text by Sora Song