Brain differences in avid players of violent video games suggest they are “callous, cool and in control”

Video games do not enjoy the best of reputations. Violent games in particular have been linked with aggression, antisocial behaviour and alienation among teens. For example, one study found that playing a mere 10 minutes of a violent video game was enough to reduce helping behaviour in participants.

However, some experts are sceptical about whether games really cause aggression and, even if the games are to blame, it remains unclear what drives their harmful effects. Earlier studies identified empathy as a key trait that may be affected by violent gameplay. Now a study by Laura Stockdale at Loyola University Chicago and her colleagues in Social Affective and Cognitive Neuroscience has taken a closer look at how gamers and non-gamers differ at a neural level, uncovering evidence that suggests chronic violent gameplay may affect emotional brain processing, although more research is needed to confirm this.

Participants were classified as frequent or infrequent players of video games depending on weekly usage – at least 30 hours of screen time per week was considered frequent, while no more than five hours a week was considered infrequent. Next, the scientists looked at the top three games their participants played, more specifically if the majority were either violent (for example, a shooter video game such as Call of Duty) or non-violent (for example FIFA). This yielded a sample of 30 frequent players of violent video games (gamers) and 31 infrequent players of non-violent games (controls). Both groups had an average age of 21 and all were male.

Participants first completed an established empathy questionnaire, with the gamers scoring lower than the controls.

For the actual experiment, the researchers recorded participants' brain waves using electroencephalography (EEG) while they completed a modified version of the "stop-signal task" (SST). The SST contained male and female faces with fearful or happy expressions and there were two types of trial: On Go trials, participants had to indicate as fast as possible whether the face was male or female by pressing a button. On No-go (stop) trials – indicated by a box around the face – participants had to withhold making any response. This version of the SST is generally considered an implicit measure of emotion processing because participants have to pay attention to the gender of the faces while trying to ignore the emotions on the faces.

The gamers and controls performed similarly on this task. Crucially, however, the brain activity of the two groups differed.

The researchers were particularly interested in three components of the EEG recordings during the stop-signal task, the so-called P100, N170 and N200/P300 (these positive or negative spikes of neural activity, known as "event-related potentials", occur at different times after the stimuli). The P100 (a positive spike 100ms after the stimulus) is one of the earliest indices of processing of visual information and has been associated with attention to emotional information. The N170 is evoked by viewing a human face, especially if it displays a negative emotion (such as fear). Finally, the N200/P300 is generally believed to be associated with inhibiting responses.

On Go trials, gamers showed a reduced P100 in response specifically to happy faces, as compared to the controls. This suggests the gamers may have been paying less attention to positive facial stimuli. Interestingly, however, this was explained by differences in empathy rather than screen time or game content. When examining only the gamers who scored high on the empathy questionnaire, they did not differ neurally from the controls. This indicates that empathy manifests in the earliest stages of how we process emotional information, and this could be one way that violent video games affect our perception. In line with this, the gamers showed an earlier N170 to happy than to fearful faces, which is the opposite of what normally happens (and the opposite of the pattern shown by the controls). This may indicate that gamers gave reduced neural priority to threatening faces, compared with normal, perhaps due to their overexposure to threatening content in games.

Finally, gamers seemed to require a lower amount of neural resources to inhibit their responses (as shown by a reduced N200/P300). It could be that video games train cognitive function and this is why gamers need fewer mental resources for this task. Alternatively, and in line with the finding of a reduced P100 amplitude, it could be that gamers simply pay less attention to emotional information, are less distracted by it and thus needed fewer mental resources for the task.

Taken together, the researchers said their results are consistent with the idea that the chronic playing of violent video games affects people's empathy and the way their brains process emotional facial expressions and control their behavioural responses. In short, chronic violent gameplay may leave players "callous, cool and in control", they said.

While interesting, this study is not free of limitations. Clearly, the biggest drawback lies with the cross-sectional design, which cannot clarify whether violent video gameplay causes lower empathy and reduced emotional processing or the other way around. Also, it is not easy to disentangle the effects of video gaming content (i.e., whether it is violent or not) and gaming duration because there was no group of frequent players of non-violent video games or infrequent players of violent video games. Plausibly, the duration gamers spend each week on their consoles could be more important than what the video game is about. For obvious reasons, any association between video gaming and empathy found here only applies to a Western context.

So more research is clearly needed. But if chronic exposure to violent video games really is associated with lower empathy and emotional callousness, this could have major implications for policymakers.

Further reading

—Cool, callous and in control: superior inhibitory control in frequent players of video games with violent content

About the author

Post written for BPS Research Digest by Helge Hasselmann. Helge studied psychology and clinical neurosciences. Since 2014, he is a PhD student in medical neurosciences at Charité University Hospital in Berlin, Germany, with a focus on understanding the role of the immune system in major depression.