Many people claim that they have so-called “addictive personalities” – a neurological propensity for substances and activities that trigger the reward centers in the brain. Science has, for the most part, backed up these claims, though new research from UC Berkely challenges the notion that some brains are “hard wired” for addiction: When presented with regular intellectually-stimulating challenges, mice were much less likely to display tendencies toward addiction.
“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.
In tracking 70 adult male mice, all were given access to a chamber where they were injected with a cocaine-like liquid. However, while some of the mice were forced to live in relatively boring isolation, others’ daily lives included exploration, learning tasks and the opportunity to suss out hidden treats and other items. A third group of mice were presented with other rewards, but no challenges.
Over nine days, the three groups were presented with different opportunities. One group was free to roam the enclosure, exploring its layout and foraging for Honey Nut Cheerios hidden beneath piles of wood chips. Another group was presented with the Cheerios whenever the exploratory mice discovered them, but did not have to hunt for themselves. The third group were left in their enclosures and fed a normal diet.
Eventually, all mice were given their injections and allowed to roam the enclosure for 20 minutes. At first all mice were keen to return to the injection chamber, but that changed over time. The authors found that the mice who had the opportunity to experience intellectual stimulation were less likely to seek refuge in the chamber where they had originally received the cocaine injections. The deprived mice, as well as the ones who received rewards with no effort, were more likely to return for a fix.
“Our data are exciting because they suggest that positive learning experiences, through education or play in a structured environment, could sculpt and develop brain circuits to build resilience in at-risk individuals, and that even brief cognitive interventions may be somewhat protective and last a relatively long time,” Wilbrecht said.
If the results can be applied to humans in any way, it would be a positive development. Drug abuse and addiction is a costly public health issue, and institutions that focus on rehabbing addiction often focus on risk factors like poverty and mental illness. Instead, a better way to fight addiction may involve giving patients more positive ways to stimulate and trigger their reward centers.