I read the article on paper before it was hidden in a paywall, so I can summarize some of the findings:
1) Rat brains are irrevocably changed by a single dose of nicotine.
2) Brains of rats that have never been exposed to nicotine (“non-smokers”), those that are currently given nicotine on a regular basis (“current smokers”), and those that used to be given nicotine on a regular basis but have been deprived of it for a long time (“former smokers”) are all distinguishable from each other.
3) The author notes that the primary effect of nicotine on addicted human smokers appears to be suppressing craving for itself.
4) The author hypothesizes that the brain has a craving-generating system and a separate craving-suppression system. (These systems apply to appetites in general, such as the desire to eat food.) He further goes on to speculate that the primary action of nicotine is to suppress craving. This has the effect of throwing the two systems out of equilibrium, so the brain’s craving-generation system “works harder” to counter the effects of nicotine. When the effects of nicotine wear off (which can take much longer than the time it takes for the nicotine to leave the body), the equilibrium is once again thrown out of balance, resulting in cravings. (The effects of smoking on weight are mentioned as support for this hypothesis.)
I read the article on paper before it was hidden in a paywall, so I can summarize some of the findings:
1) Rat brains are irrevocably changed by a single dose of nicotine.
2) Brains of rats that have never been exposed to nicotine (“non-smokers”), those that are currently given nicotine on a regular basis (“current smokers”), and those that used to be given nicotine on a regular basis but have been deprived of it for a long time (“former smokers”) are all distinguishable from each other.
3) The author notes that the primary effect of nicotine on addicted human smokers appears to be suppressing craving for itself.
4) The author hypothesizes that the brain has a craving-generating system and a separate craving-suppression system. (These systems apply to appetites in general, such as the desire to eat food.) He further goes on to speculate that the primary action of nicotine is to suppress craving. This has the effect of throwing the two systems out of equilibrium, so the brain’s craving-generation system “works harder” to counter the effects of nicotine. When the effects of nicotine wear off (which can take much longer than the time it takes for the nicotine to leave the body), the equilibrium is once again thrown out of balance, resulting in cravings. (The effects of smoking on weight are mentioned as support for this hypothesis.)