Working Memory Training Combined With Transcranial Magnetic Stimulation in Smokers

Study Summary

Smoking remains the leading cause of preventable death in the United States, and current first-line treatments leave the majority of tobacco dependent individuals unable to quit. The inability to quit despite motivation to do so, is thought to result in part, from self-control failure. Working memory (WM) deficits contribute to imbalanced self-control and allow automatic impulses to drive behavior. Thus, WM plays a critical role in addictive behavior, and is particularly relevant to smoking. Indeed, a strong link between WM and smoking has been established in the literature; most notably, degree of WM impairment and deficits in activation in associated brain regions predict time to relapse, and WM moderates the relationship between craving and relapse. Given these insights, researchers have been examining interventions that may target WM including WM training (WMT) and repetitive Transcranial Magnetic Stimulation (rTMS). WMT involves taxing this executive function repeatedly over time and has shown positive preliminary results in improving measures of self-control and reducing consumption of addictive substances. Similarly, rTMS, a non-invasive brain stimulation procedure that stimulates neuronal tissues and increases cortical excitability, has been shown to increase WM capacity and reduce craving and consumption of several addictive substances including nicotine. While these interventions have demonstrated initial promise in affecting addictive behaviors, the magnitude and durability of their effects may be limited. Recently, researchers have posited - but not yet empirically tested - that WMT administered in combination with rTMS may result in an additive or supra-additive effect in treating addictive processes. This is highly significant; the clinical utility of rTMS over current first line treatments may be limited if factors with potential to enhance its effectiveness are not examined. Given these recent advances in the literature, the primary objective of the

Primary Outcome

The Delay to Smoking Analogue Task is a behavioral choice paradigm that is sensitive to smoking medication effects in which participants earn monetary rewards for delaying initiation of cigarette smoking in 5-minute increments over a 50-minute period, following 3-hours of observed smoking deprivation. Range = 0 - 50 minutes. Higher scores indicate better ability to delay smoking.

Interventions

• DEVICE repetitive Transcranial Magnetic Stimulation
• OTHER Working Memory Training
• OTHER Sham Working Memory Training
• DEVICE Sham repetitive Transcranial Magnetic Stimulation