The achievement players feel may be more than psychological. Researchers have shown that playing video games increases the activity of dopamine, a chemical that transmits signals between cells in the brain. Movement, attention and learning are all associated with dopamine, which is thought to reinforce behavior that produces pleasure.
"Current theory is dopamine is released whenever something requires your attention or demands you concentrate on specific things," says Alain Dagher, an assistant professor at the Montreal Neurological Institute at McGill University. "So obviously video games would be an example." All addictive drugs, from cocaine to heroin, cause dopamine to be released in the brain.
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