Age-related cognitive decline is closely linked to structural changes in the brain, particularly in the hippocampus, a region essential for memory formation, spatial navigation, and learning. Hippocampal atrophy is a well-documented feature of normal aging and is strongly associated with increased risk of mild cognitive impairment and dementia. Consequently, identifying lifestyle interventions that can preserve or even enhance hippocampal structure in later life has become a major focus of neuroscience research. Compelling evidence for such an intervention comes from a peer-reviewed neuroimaging study published in PLOS ONE, which demonstrated that playing a three-dimensional video game can increase hippocampal grey matter in older adults.

The study, titled “Playing Super Mario 64 increases hippocampal grey matter in older adults,” followed adults aged 55 to 75 years who had little to no prior experience with video games. Participants were randomly assigned to one of three groups for a six-month intervention period. One group played the 3D platform game Super Mario 64, which requires continuous spatial exploration, navigation, and memory of complex virtual environments. A second group received music training in the form of piano lessons, representing a cognitively demanding but non-spatial skill. A third group served as a passive control and did not engage in any structured new learning activity.

All participants underwent high-resolution brain MRI scans before and after the six-month period. The results were strikingly specific. Only the video-game group showed a significant increase in hippocampal grey matter volume over time. In contrast, the passive control group exhibited measurable hippocampal grey-matter loss, consistent with the expected trajectory of age-related brain atrophy. This finding is particularly important because it demonstrates not merely a difference between groups, but an apparent reversal of a typical aging-related decline in the gaming group.

The comparison with the music-training group further strengthened the study’s conclusions. While piano training led to growth in brain regions associated with executive function, motor planning, and auditory processing, it did not produce significant changes in the hippocampus. This dissociation highlights that not all cognitively stimulating activities have the same effects on brain structure. Instead, the hippocampal benefits appeared to be specifically linked to the spatial, navigation-heavy demands of three-dimensional video gaming. Navigating a rich virtual environment requires the continuous formation and updating of cognitive maps, a core function of the hippocampus.

Importantly, the observed structural brain changes were not merely cosmetic findings on MRI scans. Participants in the video-game group also demonstrated improvements in short-term memory performance. These cognitive gains correlated with the increase in hippocampal grey matter, indicating that the structural changes had functional significance. This relationship strengthens the argument that the intervention enhanced hippocampal health in a way that translated into better memory performance, rather than producing isolated anatomical changes without behavioral relevance.

From a neuroscientific perspective, these findings align well with existing knowledge about experience-dependent brain plasticity. Animal studies have long shown that enriched environments and spatial learning tasks can stimulate neurogenesis and synaptic remodeling in the hippocampus. This study extends those insights to humans in later life, providing rare longitudinal evidence that targeted cognitive activities can reshape brain structure even in older adulthood.

The study’s design lends credibility to its conclusions. Random assignment, an active comparison group, a passive control group, and pre- and post-intervention neuroimaging together reduce the likelihood that the results can be explained by expectancy effects, general engagement, or preexisting differences between participants. While the sample size was moderate, the specificity and consistency of the findings make them particularly compelling.

In conclusion, the neuroimaging study published in PLOS ONE provides strong evidence that playing a three-dimensional video game such as Super Mario 64 can increase hippocampal grey matter and improve memory in adults aged 55–75 (PLOS ONE, peer-reviewed neuroimaging study). By contrast, the absence of new learning was associated with hippocampal atrophy, and non-spatial training produced benefits in other brain regions but not the hippocampus. Together, these findings demonstrate that the aging brain retains significant plasticity and that spatially demanding, immersive activities may represent a powerful, accessible tool for supporting memory and brain health in older adults.