What is the nucleus accumbens?

The nucleus accumbens is part of the brain's reward circuits and plays a role in healthy brain behavior and in pathology. It is the hub of the reward circuits and interconnects with many parts of the brain, associating with urges for rewards—specifically those that might put an individual or others at risk, such as in cases of compulsion 1. Dopamine neurons from the ventral tegmental area (VTA) send projections to various brain regions, including the nucleus accumbens, with dopamine release in this area associated with significant environmental events 2.

The nucleus accumbens contains different cell types that are modulated by neurotransmitters like dopamine and serotonin in different ways, influencing various behaviors and decisions, such as pro-social or non-aggressive interactions 3. Additionally, it has been implicated in food-related behaviors and deciding when to eat or stop eating through its association with the hypothalamus 4. The nucleus accumbens also receives projections from the amygdala complex, linking it to the dopamine system involved in craving, pursuit, and reward, which can be activated by the threat reflex in response to fear or threats 5.