The effects of approach bias modification on smoking cue-reactivity in individuals who smoke: A randomized controlled fMRI study.

Approach bias modification (ApBM), a computerized training designed to retrain involuntary approach action tendencies toward drug-related cues, has been shown to reduce relapse rates when added to treatment-as-usual (TAU) in alcohol use disorder. A potential working mechanism involves reduced neural drug cue-reactivity in reward-related brain regions. In smoking cessation, however, the efficacy and neural mechanisms of ApBM remain unclear. In this randomized-controlled trial, individuals with chronic, moderate-to-heavy tobacco dependence (N = 117, Mage = 41.5, 45.3% female) received a one-day smoking cessation intervention (TAU) and were subsequently randomized to complete seven sessions of ApBM (TAU+ApBM), Sham control training (TAU+Sham), or no training (TAU-only). Neural reactivity toward smoking-related versus neutral stimuli (smoking cue-reactivity) was assessed using functional magnetic resonance imaging (fMRI) before and after intervention. Abstinence was the primary clinical outcome. Results showed no significant group×time interactions on cue-reactivity, and ApBM did not enhance abstinence rates. In the precuneus (sensorimotor region), increased cue-reactivity following ApBM was associated with higher long-term abstinence probability, while the control groups showed the opposite descriptive pattern. In conclusion, ApBM did not reduce smoking cue-reactivity in reward-related regions, consistent with the lack of beneficial effects on clinical outcomes. Alternative neural target processes (e.g., sensorimotor-related) and respective training procedures should be explored.