Low Frequency Repetitive Transcranial Magnetic Stimulation Effects over Dorsolateral Prefrontal Cortex in Moderate Nicotine Dependent Subjects

Recent studies suggest that in some nicotine dependent patients, repetitive Transcranial Magnetic Stimulation (rTMS) has the potential to reduce craving to smoke and the amount of cigarettes smoked. In this study we assess the brain regional activation effect of one session of primed low frequency rTMS over the left Dorsolateral Prefrontal Cortex in response to smoking-related images during temporary nicotine abstinence. Ten moderate nicotine dependent subjects participated in a crossover design, comparing a single session of active versus sham stimulation. Following treatments, participants underwent a functional Magnetic Resonance Imaging study while completing a block-design cue reactivity paradigm. Outcome measures also included self-reported craving score before and after every rTMS session and cigarettes smoked in a one week period. Self-reported cravings were lower following the active stimulation; significant activation was found in areas associated with emotion control (Anterior Cingulate Gyrus and Subgenual area) and episodic memory (Precuneus and Posterior Cingulate Gyrus) as a result of the stimulation. No significant difference was found in the number of cigarettes smoked between the sham and active condition during the one week period records. This study confirms the previous evidence that rTMS can reduce cigarette cravings and provides evidence of the neural mechanism of action that take place in order to achieve these neuromodulation effects.