Spatial vs episodic memory
Shaped like a seahorse, hence its name, the hippocampus is the part of the brain that helps people to orient themselves (so-called spatial memory) and to remember past experience (episodic memory). Taxi drivers in London, England, for example, have been shown to have more developed hippocampi. More grey matter in the hippocampus means a healthier brain, all round.
However, there’s another important part of the brain called the striatum that counterbalances the hippocampus. It has an area known as the caudate nucleus that acts as a kind of “autopilot” and “reward system” – getting us home from work, for example, and telling us when it’s time to eat, drink, have sex and do other things that keep us alive and happy. The caudate nucleus also helps us form habits and remember how to do things like ride a bicycle.
Gaming has been shown to stimulate the caudate nucleus more than the hippocampus; 85 per cent of players rely on that part of the brain to navigate their way through a game. The problem is, the more they use the caudate nucleus, the less they use the hippocampus, and as a result the hippocampus loses cells and atrophies, the new study shows.
“If action video games lead to decreases in grey matter in the hippocampus [of young adults], caution should be exerted when encouraging their use… [by] children, young adults and older adults to promote cognitive skills such as visual short-term memory and visual attention,” the study says. Indeed, the “results suggest that improvement in such cognitive skills may come at a cost.”