Cannabinoids may intensify anxiety by releasing a neural brake in the brain's fear center during stress

A Northwestern University study in mice identified a possible brain mechanism behind cannabis-related anxiety, especially under stressful conditions. After receiving a synthetic cannabinoid and being exposed to a predator scent, mice froze more often, avoided the odor, and explored less. Researchers linked these behaviors to increased activity in somatostatin neurons in the central amygdala, a region involved in fear and stress. Cannabinoids appeared to weaken a natural inhibitory mechanism that normally restrains these neurons, while higher doses and environmental stress acted together to amplify anxiety-related responses. Genetically silencing the neurons reduced the behavior, suggesting they may be a target for understanding or potentially treating anxiety. The findings are based on mice and do not establish the same mechanism in humans.