Nicotine is a sympathomimetic stimulant that attaches to nicotinic acetylcholine receptors in the brain. Neuroplasticity within the brain's reward system occurs as a result of long-term nicotine use, leading to nicotine dependence.
Nicotine produces pleasing effects in your brain, but these effects are temporary. So you reach for another cigarette. The more you smoke, the more nicotine you need to feel good.
