How does nicotine affect the brain?
Nicotine is absorbed in three ways, either through the mouth with people who puff on a cigar, on a pipe, people who chew, or in the nasal mucosa or through a cigarette inhaled into the lungs. That nicotine travelling to the brain affects a specific part of the brain to create a release of chemicals that feel good. There are four or five specific areas that nicotine works on, but I would like to just focus on two that have to do with nicotine addiction. The first one is the release of nicotine in a place of the brain called the reward center. That releases a chemical called dopamine that feels great when you smoke a cigarette. It makes someone associate whatever that behavior was with "That feels great, let's do that again". In other words, laughter, running, exercise, eating food, drinking water, smoking a cigarette, or sexual release. All of those release that chemical called dopamine that human beings associate with a state of feeling good. The difference is that nicotine's affect on this reward center is almost instantaneous. Six to seven seconds after a puff of cigarette, that smoke delivers enough nicotine to create a high that no other normal physiologic experience can mimic. Nicotine stimulation from a cigarette puffed into the lungs is the most intense pleasure other than chemicals such as crack cocaine or amphetamines in releasing dopamine into the human brain to make people get the sensation that they want.
