Repetitive Transcranial Magnetic Stimulation of the Dorsolateral Prefrontal Cortex Reduces Nicotine Cue Craving

Background: Repetitive transcranial magnetic stimulation (rTMS) can noninvasively stimulate the brain and transiently amplify or block behaviors mediated through a region. We hypothesized that a single high-frequency rTMS session over the left dorsolateral prefrontal cortex (DLPFC) would reduce cue craving for cigarettes compared with a sham TMS session. Methods: Sixteen non-treatment-seeking, nicotine-dependent participants were randomized to receive either real high-frequency rTMS (10 Hz, 100% resting motor threshold, 5-sec on, 10-sec off for 15 min; 3000 pulses) or active sham (eSham) TMS over the DLPFC in two visits with 1 week between visits. The participants received cue exposure before and after rTMS and rated their craving after each block of cue presentation. Results: Stimulation of the left DLFPC with real, but not sham, rTMS reduced craving significantly from baseline (64.1 +/- .5.9 vs. 45.7 +/- 6.4, t = 2.69, p = .018). When compared with neutral cue craving, the effect of real TMS on cue craving was significantly greater than the effect of sham TMS (12.5 +/- 10.4 vs. 9.1 +/- 10.4; t = 2.07, p = .049). More decreases in subjective craving induced by TMS correlated positively with higher Fagerstrom Test for Nicotine Dependence score (r = .58, p =.031) and more cigarettes smoked per day (r = .57, p = .035). Conclusions: One session of high-frequency rTMS (10 Hz) of the left DLPFC significantly reduced subjective craving induced by smoking cues in nicotine-dependent participants. Additional studies are needed to explore rTMS as an aid to smoking cessation.