Violent video games appear to put the human brain in a mood to fight, according to a new study from Michigan State University.

In the study, 13 males played the first-person-shooter game "Tactical Ops: Assault on Terror" while in a functional magnetic resonance imaging (fMRI) system, which measures brain activity. The brain scans of 11 of the subjects exhibited "large observed effects" characteristic of aggressive thoughts. The researchers said the pattern of brain activity can be considered caused by virtual violence.

"There is a causal link between playing the first-person shooting game in our experiment and brain-activity pattern that are considered as characteristic for aggressive cognitions and effects," said René Weber, assistant professor of communication and telecommunication at MSU. "There is a neurological link, and there is a short-term causal relationship. Violent video games frequently have been criticized for enhancing aggressive reactions such as aggressive cognitions, aggressive effects or aggressive behavior. On a neurobiological level we have shown the link exists."

FMRI monitors the brain and examines how it is stimulated by different types of physical sensation or activity. Sight, sound, touch and other physical sensations show up on an FMRI image. Increased blood flow to a section of the brain indicates increased activity.

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My little cousin is a victim, he always pretend to fight enemies, this is by far true for childs. But for adults, I did not see any real-life case, I play Doom and Tactical oops, and i don't feel like killing someone