© Emily Strange/UC Berkeley News
Challenging the idea that addiction is hardwired in the brain, a new UC Berkeley study of mice suggests that even a short time spent in a stimulating learning environment can rewire the brain's reward system and buffer it against drug dependence.
Scientists tracked cocaine cravings in more than 70 adult male mice and found that those rodents whose daily drill included exploration, learning, and finding hidden tasty morsels were less likely than their enrichment-deprived counterparts to seek solace in a chamber where they had been given cocaine."We have compelling behavioral evidence that self-directed exploration and learning altered their reward systems so that when cocaine was experienced it made less of an impact on their brain," said Linda Wilbrecht, assistant professor of psychology and neuroscience at UC Berkeley and senior author of the paper just
published in the journal,
Neuropharmacology.
By contrast, mice who were not intellectually challenged and/or whose activities and diets were restricted, were eager to return to the quarters where they had been injected with cocaine for weeks on end."We know that mice living in deprived conditions show higher levels of drug-seeking behavior than those living in stimulating environments, and we sought to develop a brief intervention that would promote resilience in the deprived animals," said study lead author Josiah Boivin, a Ph.D. student in neuroscience at UC San Francisco who conducted the research at UC Berkeley as part of his thesis work.
Drug abuse and addiction rank among the world's more costly, destructive and seemingly insurmountable problems. Previous studies have found that poverty, trauma, mental illness and other environmental and physiological stressors can alter the brain's reward circuitry and make us more susceptible to substance abuse.
The good news about this latest study is that it offers scalable interventions against drug-seeking behaviors, albeit through evidence based on animal behavior.
Comment: This underscores the importance of meaningful connections with family and friends. Not only is social isolation a risk factor for depression, but has also been linked to addiction.