Watching violent TV, video games desensitizes teenagers and may promote more aggressive behavior

October 19, 2010

Watching violent films, TV programmes or video games desensitises teenagers, blunts their emotional responses to aggression and potentially promotes aggressive attitudes and behaviour, according to new research published online today in the Oxford Journal Social Cognitive and Affective Neuroscience (Tuesday 19 October).

Although previous research has suggested that people can become more aggressive and desensitised to real-life violence after repeatedly viewing programmes, little is known about how the extent of watching such programmes and the severity of the aggression displayed affects the brains of adolescents. "It is especially important to understand this because adolescence is a time when the brain is changing and developing, particularly in the parts of the brain that control emotions, emotional behaviour and responses to external events," said Dr Jordan Grafman, who led the research.

Dr Grafman, senior investigator at the National Institute of Neurological Disorders and Stroke, National Institutes of Health (Bethesda, USA), and colleagues recruited 22 boys between the ages of 14-17 to the study. The boys each watched short, four-second clips of violent scenes from 60 videos, arranged randomly in three lots of 20 clips. The degree of violence and aggression in each scene was low, mild or moderate, and there were no extreme scenes. They were asked to rate the aggression of each scene by pressing one of two response buttons at the end of each clip to say whether they thought it was more or less aggressive than the previous video. The boys were positioned in a scanner that collected data on their while they watched the videos. They also had electrodes attached to the fingers of their non-dominant hand to test for skin conductance responses (SCR). This is a method of measuring the electrical conductance of the skin, which varies with moisture (sweat) levels and is a sensitive way of measuring people's emotions and responses to internal or external stimuli.

Dr Grafman said: "We found that as the boys were exposed to more violent videos over time, their activation in brain regions concerned with emotional reactivity decreased and that was reflected in the data from the functional MRI and in the skin conductance responses."

Data from the SCR showed that the boys became more desensitised towards the videos the longer they watched them and also that they were more desensitised by the mildly and moderately violent videos, but not the ones that contained a low degree of violence. Data on brain activation patterns showed a similar effect. In particular, the area known as the lateral orbitofrontal cortex (lOFC), which is thought to be involved in emotions and emotional responses to events, showed increasing desensitisation over time, and this was most marked for the most aggressive videos (showing moderate violence) in the study.

The researchers also found that boys who had the most exposure to violent media in their daily lives, as measured by screening tests and questions in their initial meeting with the researchers, showed the greatest desensitisation.

Dr Grafman said: "The important new finding is that exposure to the most violent videos inhibits emotional reactions to similar aggressive videos over time and implies that normal adolescents will feel fewer emotions over time as they are exposed to similar videos. This finding is driven by reduced posterior brain activation and therefore the frontal lobe doesn't react as it normally would.

"The implications of this are many and include the idea that continued exposure to violent videos will make an adolescent less sensitive to violence, more accepting of violence, and more likely to commit aggressive acts since the emotional component associated with aggression is reduced and normally acts as a brake on aggressive behaviour. No prior study has examined this from the complete perspective we had that included behaviour, brain activation, and SCRs in adolescent brains."

As the study recruited only boys, it is not possible to say whether the same effect would be seen in girls. "The incidence rate of aggression in females, even in female teenagers that are exposed to some of the same biopsychosocial challenges as male adolescents, is low and raises the questions of what brain mechanisms and autonomic differences are associated with this gender difference," write the authors.

They conclude: "We propose that exposure to aggressive media results in a blunting of emotional responses, which in turn may prevent the connection of consequences of aggression with an appropriate emotional response, and therefore may increase the likelihood that aggression is seen as acceptable behaviour."

Dr Grafman believes that the findings of the study can be extrapolated to the way people would behave in real life situations. "The electronic media concerned with aggression does stimulate structures in the brain that are typically activated when people imagine being aggressive and, we assume, when they actually are aggressive. Most people can distinguish between playing a video game and real live behaviour, but given the right circumstances where the rules are a bit more ambiguous (what if a bully provokes me) and provocative (someone is trying to take my lunch money), would an adolescent tend to be more aggressive and accept that aggression as normal behaviour given prior exposure to video games? I think so. Particularly if they are a heavy user of games and, in our device-driven world, that will be more and more likely in the future."

More information: [1] "Fronto-parietal regulation of media violence exposure in adolescents: a multi-method study". Social Cognitive and Affective Neuroscience. Published online under advance access. doi:10.1093/scan/nsq079

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1.6 / 5 (7) Oct 19, 2010
Well, now ain't that a surprise? Who would have thought that what family focused groups have been saying for decades has now been "shown to be true"?

I can make the bet that the same is true for promiscuous sexual behaviour, what with all the sexually stimulating scenes in movies and the like. These promote the now socially accepted idea that it's OK to have sex outside of marriage and that marriage [ as between heterosexuals] is an outmoded and distasteful practice.
We will reap what we sow. Violence and promiscuous sex. Violent promiscuous sex.
3.7 / 5 (3) Oct 19, 2010
As kevinrtrs stated above -- this is not new information, science or other. The fact that television and film are the most costly behavior conditioning media is clear evidence of their impact on our culture for decades. My masters thesis was on the effect of violence in the media and at the time 29 years ago -- there were already 1,100 studies establishing the correlation of positive as well as negative behavior and media.
4.5 / 5 (4) Oct 19, 2010
OR it means that people who have watched a lot of violent videos are becoming desensitized to... violent videos.

There's a pretty significant difference in violence in real life (especially when it relates to YOU) than there is between violence involving strangers on a TV. Even moreso when that violence is from a video game in which nothing is real.

I just feel like conclusions such as...

"continued exposure to violent videos will make an adolescent less sensitive to violence, more accepting of violence, and more likely to commit aggressive acts since the emotional component associated with aggression is reduced and normally acts as a brake on aggressive behaviour."

...are taking a bit of a leap.
3 / 5 (2) Oct 19, 2010
It is a leap and indeed all this proves is that we can become desensitized to FICTITIOUS violence, not necessarily to REAL violence, especially when there's a question of perpetrating it ourselves.

If anything, modern life and everything in it have been REDUCING the incidence of interpersonal violence. Just check the statistics of ACTUAL violence throughout recent history, especially where violent video games have been available. Then we can talk.
3.3 / 5 (3) Oct 19, 2010

I rate you guys 3s, because I think that you are only partly right.

Firstly, no one -at least no one in their right mind- is going to be desensitized to violence against themselves. That is a given.

Nextly, I think what this study -and others like it- suggests, is that viewing violent video games desensitizes us to violent video imagery in general, and that therefore, ALL violent video desentizes us to visually perceived violence.

The authors of this study plainly failed to address this issue, as it is the only one that is of any relevance to the question.

IMO, the only relevant point is that all violent visual imagery is desensitizing, and, since most of the news we view is video, you find yourself feeling less emotional reaction when viewing even the most egregious violence, which leads to less outrage and outcry against barbarism.

That is the true danger here.

not rated yet Oct 20, 2010
It is so easy to be critical. News media does not sell on good he same applies to other forms of mwedia. We have to convince those who buy it not to buy into it. So we need to continue to have studies, good or bad, to prove to and convince people, especially parents, that material like this is not good for development. The story continues.
5 / 5 (1) Oct 20, 2010

My main point was against the conclusions that are being drawn about the viewing of violent materials leading to violent behaviours from the study based on the evidence they've gained.

I didn't even mean so much as violence against a person, but violence in general that that person was involved in (ie. watching someone get punched on TV and throwing a punch are completely different things).

Your point at the bottom about desensitization via news leads to less outrage and outcry is pretty interesting, however I believe that kind of desensitiaztion isn't necessarily involved in violent imagery. That would be more desensitization to the actual acts of violence due to repeated reporting rather than just the imagery since, really, not much real imagery of that sort is seen on the news (of people actually getting tortured/murdered/etc).

If anything you'd think seriously violent imagery would cause more outrage/outcry would it not?
not rated yet Oct 24, 2010
This study shows nothing except Grafman is desensitized through long exposure to weak illogical scientific reasoning and so is indulging it more and more himself. How on earth can anyone come to any conclusions from this brief test other than that anyone would get bored (=desensitized) after watching 4 second clips of *anything* from a mere 60 videos?

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