select search filters
roundups & rapid reactions
factsheets & briefing notes
before the headlines
Fiona fox's blog

expert reaction to study on playing action video games and hippocampal grey matter

Publishing in Molecular Psychiatry, researchers have looked at the plasticity of the hippocampus in those who play video games. They report that different types of games, depending on the type of navigational strategy are associated with different effects on the hippocampal system.


Prof Andrew Przybylski, Associate Professor and Senior Research Fellow, Oxford Internet Institute, University of Oxford, said:

“The study purports to test an interesting idea, that exposure to different kinds of video game play might have an effect on observable differences in brain activity at a later time. Given the wide-ranging debates concerning the possible benefits of so-called ‘brain-training’ games research purporting to show the opposite, cognitive downsides, are likely to garner public attention. That understood there are at least three reasons to be wary of interpreting this research as providing substantive evidence that “playing action video games can actually harm your brain”.

“First and foremost, the press release does not accurately reflect the results of the study. The hypotheses tested do not relate to harm and the paper does not provide evidence that 90 hours of play, the ‘treatment’, leads to harm. Thus the interpretation of harm, although attention-grabbing, was not peer reviewed and appears to have been introduced afterwards. This framing is a worrying over-reach that could mislead readers.

“Second, the studies lack the statistical power needed to demonstrate a reliable effect. In this paper the experimental studies have only 43 and 31 participants. This means real results are unlikely to be found and statistical noise will look like a meaningful trend to overly optimistic researchers. Our research ( ) suggests this experiment, like many others examining media effects, are similarly fatally flawed. Extrapolating from small-scale and noisy studies like these is extremely problematic.

“Third, the studies lack sufficient detail to conclude they have been rigorously done. Though we know that participants were ‘semi-randomly’ assigned to play different kinds of games (so-called ‘action’ vs. ‘3-d’ platform games), these are not natural categories and it is not clear which games were played and how much. Because this detail is lacking we have no idea what specific features of play might drive the effect the researchers are claiming to have demonstrated. This undermines the value of the research because it is impossible to know if the ‘media diet’ the authors describe is representative of what video game players do in the wild.

“Taking all of this together it is best that readers are sceptical of the findings. The methods and hypotheses of the study were not registered in advance of data collection. Studies like this do not replicate well when held to a higher standard of evidence1. This is not the first time this research group has drawn conclusions that go well beyond their evidence and readers would be wise to take the present claims with a generous helping of salt.”




* ‘Impact of video games on plasticity of the hippocampus’ by West et al. will be published in Molecular Psychiatry at 00:01 UK time on Tuesday 8th August, which is also when the embargo will lift. 


Declared interests

Prof Andrew Przybylski: No conflicts of interest.

in this section

filter RoundUps by year

search by tag