Video game effects on the brain have been heavily debated for decades, with a chief concern being that action video games like Call of Duty influence aggressive and violent behavior. Some experts believe these adverse effects have been overstated, but a new study from the Université de Montréal has found habitually playing them may actually harm your brain.
Researchers had about 100 people play shooter games like Call of Duty, Killzone, and Borderlands 2, along with 3D Super Mario games for 90 hours. They found that participants who favor their brain's caudate nucleus — an area associated with the brain's reward system and habit formation — had less grey brain matter in their hippocampus after playing action games.
The hippocampus is a major part of the brain that helps maintain spatial and episodic memories, according to the study. And reduced grey matter in this part of the brain has previously been linked to higher risks of brain illnesses, including depression, schizophrenia, PTSD, and Alzheimer's disease.
Researchers found that 85% of gamers rely on their caudate nucleus (also known as "response learners") more than their hippocampus (spatial learners) while navigating action video games. This adversely affects the hippocampus because as the amount of grey matter increases in the caudate nucleus, it decreases in the hippocampus. Meanwhile, playing the 3D Super Mario games for 90 hours resulted in increased grey matter in the hippocampus for all the participants, according to the study.
To counter potential long-lasting damage, the study authors suggest that response learners would benefit from strategies that target spatial learning. For example, video game designers could alter modern action games by removing in-system navigational tools. This would allow the gamer to get around using landmarks included in the world of the game, which can strengthen spatial learning.