Commentary: Examining The Brains Of Frequent Game Players

As mentioned in a few places already (BBC, Reuters) a recently published study has reported that frequent gamers (defined as individuals who reported playing more than 9 hours a week) have significantly more brain mass in the area known as the left ventral striatum than infrequent gamers (as shown via fMRI scans). Frequent gamers were also found to show more activation in this area when performing a simple reaction time task (the Monetary Incentive Delay or "MID" task) which aims to test brain activation during reward anticipation and reward feedback. So in other words to test activation when you are looking forward to, and after you have received a reward. 

Now the way this has been reported so far has been relatively non-sensationalist (note the 'differ' on the BBC's headline - and that they mention that this is just correlational at the moment - i.e. perhaps it is caused by gaming or perhaps people with this type of brain like to game) - however since I have taken the time to read the published article, and have a background in psychology and biology I thought I would just provide some additional commentary on the article.

The 'Addiction Centre' of the brain

First off probably the reason why this is being reported in the media is that the ventral striatum is an area of the brain that is strongly associated with the dopamine system. Dopamine is a neurotransmitter in our brain associated with how we process rewards, and therefore the ventral striatum is sometimes referred to as the 'reward centre' of the brain. It is also however sometimes referred to as the 'addiction centre' of the brain. 

This is because it is generally considered that anything that is rewarding, and therefore activates the dopamine system, can be addictive. This is supported by, amongst other things, research showing that increased activation of this area (such as in some Parkinson’s patients or in drug addicts) can lead to increases in addictive behaviour. Of particular relevance to gaming people who are problem gamblers (or addicted if you like) also have increased activation in this area.

So one way to interpret this data, and certainly the way it is being reported, is that video games may become addictive in frequent gamers due to changing brain structures and patterns of activation in this area of the brain. Another (as mentioned in the press so far and the article) is that individuals who already have differences in these areas may be attracted to video gaming and may become addicted due to their pre-existing brain differences. As with most of these things the smart money would probably be on a mixture of both. 

Based on what I see in the paper these are both valid conclusions. However, I would like to add a few more details for you that are mentioned in the paper but not in the media reports I have seen. Firstly before you get grumpy at the scientists (who seem very reasonable and even handed to me) they admit that they did not examine problem or extreme gamers. This may have consequences for their findings but it may not - and again the authors acknowledge that while it is an exciting finding (as a researcher I have to say results nearly always are) much more work needs to be done. 

The authors also mention that while increased activation in this area has been related to other problems with addiction the evidence around increase of volume in this area is not as consistent. This is because while some studies have found increased volume in this area in substance abusers other studies have shown decreases in this area in similar populations.

Other explanations? 

The addiction interpretation is certainly possible. It is also interesting, however, to also mention, as the authors do in the article, that the ventral striatum is involved in more than just the processing of rewards. It is also involved in motivation, locomotion (movement), and executive function. This last component, executive function, is particularly interesting in light of these findings.

Executive function essentially refers to decision making and includes such abilities as being able to quickly switch between tasks, make probability judgements, reason, and working memory capability. All of which, as the authors of the article correctly point out, have been found to benefit from video game playing. Therefore an alternate (or complementary) explanation for the findings of this article is that there is increased volume and activation in this area in frequent game players due to improvements in executive function related to video game playing (or that people with higher levels of executive control play more video games - remember this is correlational not causal at the moment).

Again this is something that the authors of the article do mention it is just that I haven't seen it in media reports as of yet. 

Ultimately research in this area is always interesting (at least to me) and will always get media attention. The researchers state that their plan now is to get adults who have never played (or played very infrequently) video games to play and see if their brain structure changes - so there you go publishers at the very least these guys trying to make some new gamers for you.