Cannabis-dependent men show exaggerated cognitive performance deterioration during psychosocial stress compared to controls, despite reporting similar stress levels and cardiovascular responses. Brain imaging revealed that this performance decline was accompanied by reduced activity in the precuneus and increased connectivity between the precuneus and the superior frontal gyrus during stress exposure. The findings provide first evidence linking chronic cannabis use to altered neural stress processing, specifically deficient recruitment of the precuneus, which may underlie stress-induced cognitive impairments in cannabis users.
The medial prefrontal cortex (mPFC) is central to emotional experience, with a functional gradient along its dorsal-ventral axis: dorsal regions primarily engage in negative emotions, while ventral subdivisions facilitate positive (safety) experiences and show a duality—representing emotions abstractly while generating individualized interpretations. During emotion regulation, the dorsal mPFC supports explicit-control strategies like reappraisal, and the ventral mPFC mediates implicit-automatic regulation through extinction learning. Through interactions with the default mode network and other brain networks, the mPFC enables the construction of nuanced, contextualized emotional experiences fundamental to adaptive behavior. Understanding these mechanisms may advance affective neuroscience and inform therapeutic approaches for mental disorders with default mode network dysfunction.