Nicotine Boosts Mood, Brain Dopamine Levels

Just handling, lighting, and drawing on a cigarette can alleviate craving and anxiety in a person addicted to nicotine, NIDA researchers have found. Chronic smokers in a study led by Dr. Arthur Brody at the University of California, Los Angeles, reported relief from these withdrawal symptoms after smoking cigarettes that, unbeknownst to them, contained only trace amounts of nicotine. Another desired effect of smoking, a lift in mood, required fully nicotinized cigarettes, however.

Using positron emission tomography on the 62 study participants, the researchers correlated the degree of mood elevation with the size of the nicotine-triggered surge in levels of the neurotransmitter dopamine in the brain's main reward area, the ventral striatum. Standard cigarettes raised these levels an average of 8 percent, while denicotinized cigarettes increased them by only 1 percent.

Although the participants' reported decrease in cigarette craving did not correlate with smoking-induced changes in dopamine levels in the reward pathway, it may reflect dopamine activity in other parts of the brain or sensory aspects of cigarettes, says Dr. Brody.

Neuropsychopharmacology 34(2):282-289, 2009. [Full Text (PDF, 188KB)]