"My God," you think, as you swirl your drink in front of you, "I could use a smoke right now." The urge is all the stronger because of all those memories of past times with friends and a cigarette. Your life just seemed more fun when you were smoking. Was life more exciting before you kicked the habit? It sure seems so.
It's not all your imagination. A recent study
at Baylor College of Medicine says nicotine actually tricks the brain into linking cigarettes and the environment you're in when you smoke them. The brain is wired to reward you with a shot of dopamine when you do things that ultimately end up in your living longer. The problem is that this mechanism was built to reward us in an environment where scarcity was the norm. So, we get a reward when we eat, for example. Move this forward into our age of excess and the result is rampant obesity.
This mechanism also fires when we're in an environment that typically prompts these reward releases of dopamine. We're driven to spend more time there. If we typically get rewarded in one location (i.e. great dinners at our parent's house) and not another we develop a subconscious affinity for the rewarding environment.
So, what do cigarettes do to this hard wired reward mechanism? They short circuit it in a couple ways. Nicotine not only hijacks the dopamine reward system, but it also alters the way our memories are laid down, drawing us back to environments where we smoke. Nicotine supercharges the hippocampus, a part of the brain that lays down new memories. The Baylor study, which was done on mice, found that mice "on nicotine" recorded twice the neuronal activity as the control group. Nicotine tricks the brain into believing that smoking is a beneficial activity and laying down memories to reinforce this belief. It's a double whammy for those trying to kick the habit.