Appetitive responses toward smoking-related stimuli in abstinence-motivated, non-deprived individuals with chronic tobacco dependence: A multi-methodological investigation.

Abstract

Appetitive responses, such as approach biases, are thought to play a crucial role in smoking. This study aimed to compare responses toward smoking-related stimuli with responses in control conditions (e.g. non-approach or neutral stimuli) using a multi-method approach. By examining associations between response measures and with smoking-related variables, the study sought to extend understanding of their role in abstinence-motivated, non-deprived individuals with chronic tobacco dependence. Cross-sectional study conducted at a university laboratory and magnetic resonance imaging (MRI) scanner in Munich, Germany. 362 chronically smoking individuals (51.38% female; data collection: November 2019-March 2023) with moderate-to-severe tobacco dependence, enrolled in a smoking cessation study, allowed ad libitum smoking prior to assessment. Responses toward smoking-related stimuli were assessed using cognitive-behavioral (reaction-time-based approach biases), psychophysiological (electromyography: corrugator supercilii, zygomaticus major and orbicularis oculi for acoustic startle reflex) and neural (functional MRI: regions relevant to smoking cue-reactivity) measures. Smoking-related variables were cigarettes per day, tobacco dependence severity and craving. Split-half reliabilities were estimated for all measures. Participants exhibited a statistically significantly attenuated acoustic startle reflex toward smoking-related versus neutral stimuli (P < 0.001, Rosenthal's r = 0.39), while no statistically significant differences emerged for other psychophysiological or cognitive-behavioral measures. Neural measures showed statistically significantly heightened reactivity toward smoking-related versus neutral stimuli in sensory and motor regions (e.g. precuneus; P < 0.001, Rosenthal's r = 0.44) but reduced activity in reward-related regions (e.g. striatum; P = 0.021, Cohen's d = 0.22). Higher craving was statistically significantly associated with stronger appetitive responses on some measures from all assessment methods (Ps ≤ 0.041), whereas greater tobacco dependence and smoking behavior were linked to reduced neural reactivity toward smoking-related stimuli (Ps ≤ 0.036). No statistically significant associations emerged between measures from different methods (factor loadings ≤ 0.145, Ps ≥ 0.076). Differences scores between conditions (rel. = -0.351 to 0.837) were generally less reliable than their individual components (rel. = 0.619 to 0.964; excluding one exception) CONCLUSIONS: Appetitive responses toward smoking-related stimuli may play a limited role in abstinence-motivated, non-deprived individuals with chronic tobacco dependence, whereas habitual motor responses could be more crucial.