A single 15-minute session of high frequency transcranial magnetic stimulation (TMS) over the prefrontal cortex temporarily reduced cue-induced smoking craving in nicotine-dependent individuals, a new study has shown.
Nicotine activates the dopamine system and reward-related regions in the brain. Nicotine withdrawal naturally results in decreased activity of these regions, which has been closely associated with craving, relapse, and continued nicotine consumption.
One of the critical reward-related regions is the dorsolateral prefrontal cortex, which can be targeted using a brain stimulation technology called transcranial magnetic stimulation.
Transcranial magnetic stimulation is a non-invasive procedure that uses magnetic fields to stimulate nerve cells. It does not require sedation or anesthesia and so patients remain awake, reclined in a chair, while treatment is administered through coils placed near the forehead.
Dr. Xingbao Li and colleagues at Medical University of South Carolina examined cravings triggered by smoking cues in 16 nicotine-dependent volunteers who received one session each of high frequency or sham repetitive transcranial magnetic stimulation applied over the dorsolateral prefrontal cortex.
This design allowed the researchers to ferret out the effects of the real versus the sham stimulation, similar to how placebo pills are used in evaluating the effectiveness and safety of new medications.
They found that craving induced by smoking cues was reduced after participants received real stimulation. They also report that the reduction in cue-induced craving was positively correlated with level of nicotine dependence; in other words, the TMS-induced craving reductions were greater in those with higher levels of nicotine use.
The study was published in Biological Psychiatry.