The effects of video games on the brain is a highly controversial topic, as both benefits and drawbacks have been found, depending on the content of the video games played. Changes in brain regions associated with vision, motor skills, attention, reward, planning, emotion and social behavior are found after playing video games.
Changes in Vision
According to a 2009 study published in Nature Neuroscience by Li and Bavelier, playing action video games can improve contrast sensitivity. Interestingly, no improvement was found from playing non-action video games. Contrast sensitivity is the fine discrimination between shades of gray and is important for such activities as driving at night, piloting or reading X-rays.
Contrast sensitivity decreases with age, so enhancements to it are of therapeutic interest. This increase in contrast sensitivity after video games is likely due to brain changes, as opposed to changes in the eyes, because video games enhance attention, and attention increases the activity of brain cells in a region called the visual cortex, which processes vision. Another study, published in 2003 in Nature by Green and Bavelier, corroborates this theory because it found video game playing resulted in enhanced visual attention to the borders of the computer screen.
Changes in Social Behavior
Video game playing may change social skills depending on the content of the video game. Video games requiring team playing can enhance collaboration skills, according to a 2006 study by Hämäläinen and Häkkinen. Playing video games which encourage violence increases violent behavior, while playing video games that promote characters aiding each other in nonviolent ways have more “pro-social” behavior, according to a 2009 study by Gentile and Sakamoto.
Changes in Brain Activity
Playing violent video games releases dopamine in a brain region called the striatum. Dopamine is a neurotransmitter associated with motivation and reward. Other brain regions are impacted by video games. A functional magnetic resonance imaging (fMRI) study published in 2006 by Weber and Mathiak found that before firing weapons in violent games, there is more activity in the dorsal anterior cingulate cortex, an area associated with planning, while during and briefly after firing a weapon, there is less brain activity in the rostral anterior cingulated cortex and amygdala, two regions associated with emotion.
Change in Motor Skills
Video games require repetitive behaviors, which can strengthen connections between brain cells and thus enhance motor skills. One example is that video game playing increases surgical skills, according to a 2007 study by Rosser and Merrell. Another example is that stroke patients who have damage to the brain improved their motor skills after playing video games, according to research presented at the American Stroke Association's International Stroke Conference 2010.