The pleasure provided by nicotine is complicated. Nicotine molecules find their way to receptors (little harbours) on several types of brain cells. The first type processes acetylcholine, one of the brain’s main neurochemicals. Acetylcholine makes us more alert and focused, it powers consciousness itself, so nicotine enhances our sense of being alive, if only slightly. The second type of brain cell colonised by nicotine processes dopamine is the neurochemical that causes us to feel attraction and anticipation. Dopamine is a well-known culprit in all kinds of addictions. It’s been linked with pleasure conventionally, but its main function is to promote desire and goal pursuit rather than pleasure per se. In fact, nicotine receptors are scattered all over the brain, and they turn up the tap on other neurochemicals, in charge of every brain state from arousal to relaxation.
As with other addictive drugs the comforts of nicotine are outweighed by the discomforts attendant on quitting. All those receptors in all those regions grow accustomed to their nicotine diet after several months. They adjust to that diet, so they are relatively starved when it’s suddenly withdrawn. The positives rebound into proportional negatives, and we feel that backlash in our bodies as they receive distress signals from our brains. Just as nicotine makes us feel good in subtle and complex ways, nicotine withdrawal makes us miserable in subtle and complex ways. That may be why, compared to other drugs, nicotine is the hardest to kick. Gene Heyman, an American addiction researcher, compiled epidemiological data on the average time to quit several drugs, and here are his surprising findings:
“With the onset of dependence as the start date, half of those ever addicted to cocaine had quit using this drug at clinically significant levels by year four, and the half-life for marijuana dependence was six years. In contrast, alcohol and cigarette dependence had much longer half-lives. For alcohol, the 50% remission mark was not reached until year 16, and for cigarettes, it took on average 30 years for dependent smokers to quit.” (GM Heyman, Quitting drugs: Quantitative and qualitative features. Annual Review or Clinical Psychology, 2013)
Marc Lewis (24 June 2015) Why is nicotine addictive? You asked Google, here’s the answer [online newspaper]. Retrieved from http://tinyurl.com/nk4s4mp