Recent research from the University of Mississippi has revealed how repeated stress fundamentally alters brain function in ways that persist for weeks, potentially explaining why some individuals become more vulnerable to substance use disorders. The findings, published in the journal eNeuro, offer critical insights into the neurological mechanisms that link chronic stress to increased addiction risk.
How Stress Alters Decision-Making and Reward System…The study revealed a troubling pattern in brain activity following repeated stressful events. Activity in the prefrontal cortex decreased significantly, potentially compromising the brain’s ability to make sound judgements. Simultaneously, activity in the ventral tegmental area initially increased, heightening the desire for rewards, before dropping below normal levels in subsequent weeks.
This dangerous combination creates a perfect storm: diminished capacity for rational decision-making coupled with intensified cravings for immediate gratification, followed by a persistent “reward deficit” where normal rewards no longer provide satisfaction. The research demonstrates that chronic stress makes risky behaviours more tempting and harder to resist.
“Stress decreases the percentage of people who can just walk away from drugs and increases the risk of developing substance use disorder,” Del Arco noted.