Welcome to the “Addictions & Recovery” group, @wgatap21.
Most people recognize that smoking causes serious harm, yet many people continue to smoke––why? Smoking or nicotine addiction is an extremely complex process and psychological, behavioral factors play a big role!
The brain has its own receptors for nicotine – so-called ‘nicotinic acetylcholine’ receptors. Many of these are located in the area of the dopamine ‘reward’ pathway. Dopamine release is usually concerned with naturally rewarding activities (such as eating, drinking, sexual activity, and so on), but addictive drugs can ‘hijack’ this system resulting in faster and greater amounts of dopamine release. When nicotine activates the nicotinic receptors brain, it results in massive dopamine release. https://www.ncbi.nlm.nih.gov/pubmed/7982062
Smoking also taps into the negative reinforcement system – via the withdrawal syndrome. When a regular smoker stops smoking, they experience bad withdrawal symptoms (e.g. irritability, depression, restlessness, poor concentration, increased appetite) and strong urges to smoke. Nicotine ingestion, especially via smoking, extinguishes these symptoms.