“The brain registers all pleasures in the same way, whether they originate with a psychoactive drug, a monetary reward, a sexual encounter, or a satisfying meal. In the brain, pleasure has a distinct signature: the release of the neurotransmitter dopamine in the nucleus accumbens, a cluster of nerve cells lying underneath the cerebral cortex (see illustration). Dopamine release in the nucleus accumbens is so consistently tied with pleasure that neuroscientists refer to the region as the brain’s pleasure center.
All drugs of abuse, from nicotine to heroin, cause a particularly powerful surge of dopamine in the nucleus accumbens. The likelihood that the use of a drug or participation in a rewarding activity will lead to addiction is directly linked to the speed with which it promotes dopamine release, the intensity of that release, and the reliability of that release.”
http://www.helpguide.org/harvard/addict ... _brain.htm
According to Mike Langlois of Gamer Therapist:
True enough, but as “Joe” in comments points out:“Does this mean that people can’t have problem usage of video games? No. But what it does mean, in my opinion, is that we have to stop treating behaviors as if they were controlled substances. Playing video games, watching television, eating, and having sex are behaviors that can all be problematic in certain times and certain contexts. But they are not the same as ingesting drugs, they don’t cause the same level of chemical change in the brain.”
So what are the effects of all this extra dopamine on the brain?“If the peak dopamine exposure from video games is indeed roughly a 100% increase above baseline or normal level while playing, then the cumulative exposure above baseline over several hours daily (as is common for kids playing video games) rivals the cumulative extra exposure from some of the drugs in the charts above. For example from the charts above, 10 mg/kg morphine causes release 100% above baseline for 2 hrs and 50% above for ~1 hr while cocaine averages ~150% above baseline for 4 hrs. If we compare this to video gaming at 100% above baseline, then the exposure above baseline from 2 to 3 hours of video games is similar to the 10 mg/kg of morphine and 4 to 6 hours is comparable to cocaine. And while one might deplete cash fast with daily hits of morphine or cocaine, video games are cheap and easily accessible enough to be used daily.”
http://gamertherapist.com/blog/2011/11/ ... addiction/
“Continuous use of such drugs robs them of their power to induce euphoria. Addictive substances keep the brain so awash in dopamine that it eventually adapts by producing less of the molecule and becoming less responsive to its effects. As a consequence, addicts build up a tolerance to a drug, needing larger and larger amounts to get high. In severe addiction, people also go through withdrawal—they feel physically ill, cannot sleep and shake uncontrollably—if their brain is deprived of a dopamine-stimulating substance for too long. At the same time, neural pathways connecting the reward circuit to the prefrontal cortex weaken. Resting just above and behind the eyes, the prefrontal cortex helps people tame impulses. In other words, the more an addict uses a drug, the harder it becomes to stop.”
http://www.scientificamerican.com/artic ... ng/?page=2
“Lower levels of dopamine D2 receptor availability have been previously reported in cocaine abusers, alcoholics, and heroine abusers. This study extends this finding to methamphetamine abusers. The association between level of dopamine D2 receptors and metabolism in the orbitofrontal cortex in methamphetamine abusers, which replicates previous findings in cocaine abusers, suggests that D2 receptor-mediated dysregulation of the orbitofrontal cortex could underlie a common mechanism for loss of control and compulsive drug intake in drug-addicted subjects.”
http://www.ncbi.nlm.nih.gov/pubmed/11729018