imitating the brain ’ s natural chemical messengers and ( 2 ) by overstimulating the ‘ reward circuit ’ of the brain . Some drugs ( e . g ., marijuana and heroin ) have a similar structure to chemical messengers called neurotransmitters , which are naturally produced by the brain . This similarity allows the drugs to ‘ fool ’ the brain ’ s receptors and activate nerve cells to send abnormal messages .”
“ Other drugs , such as cocaine or methamphetamine , can cause the nerve cells to release abnormally large amounts of natural neurotransmitters ( mainly dopamine ) or to prevent the normal recycling of these brain chemicals , which is needed to shut off the signaling between neurons . The result is a brain awash in dopamine , a neurotransmitter present in brain regions that control movement , emotion , motivation , and feelings of pleasure . The overstimulation of this reward system , which normally responds to natural behaviors linked to survival ( eating , spending time with loved ones , etc .), produces euphoric effects in response to psychoactive drugs . This reaction sets in motion a reinforcing pattern that ‘ teaches ’ people to repeat the rewarding behavior of abusing drugs .” In other words , “ overstimulating the system with drugs ... produces euphoric effects , which strongly reinforce the behavior of drug use — teaching the user to repeat it .”
Curiously , addicts are often extraordinarily intelligent , highly sophisticated thinkers . It is not a lack of intellectual capacity that they suffer from . If we look to history , it becomes painfully obvious that some of the most brilliant , influential minds among us have suffered from this tragic disease . To name a few : Alexander the Great , Michael Jackson , Karl Marx , Nero , Hunter S . Thompson , Charles Bukowski , Ernest Hemingway , F . Scott Fitzgerald , David Bowie , William Faulkner , Edgar Allan Poe , Mark Twain , Nikola Tesla , Cat Stevens , Piotr Ilyich Tchaikovski , Elton John , Vincent Van Gogh , Charles Dickens , Lord Byron , Sinclair Lewis ,