Abstract
BACKGROUND: Alcohol and cigarettes are commonly used together, but little is known about their joint motivational impact. Cue reactivity studies have customarily examined alcohol and smoking cues in isolation, despite the potential for cues to elicit stronger motivational responses when combined. This study used a validated cue reactivity procedure (Choice Behavior Under Cued Conditions) systematically to disentangle the separate and joint effects of alcohol and cigarette cues on substance use motivation. METHODS: Participants were 110 adults (M(age) = 34.0, SD = 10.8) who consumed both cigarettes and alcohol. Participants completed 40 cue reactivity trials with four in vivo cue types: water, alcohol, cigarette, and combined cigarette and alcohol. Participants rated their craving prior to receiving opportunities to spend real money to gain access to the cues. Spending larger amounts of money increased the probability that the substance(s) would be available for consumption. When granted access, participants took one cigarette puff and/or sip of the beverage. A multimethod approach assessed three key motivational indices: craving, drug-seeking (spending, latency to access the cue), and consumption (puff duration, alcohol consumed). Effects of cue type and rates of substance use (cigarettes per day, drinks per day, relative frequency of co-use) were assessed using hierarchical linear models. RESULTS: Both alcohol and smoking cues enhanced cue-specific craving but not craving for the alternative substance. In a novel finding, combined cues elicited higher craving and greater spending than single-drug cues. All drug cues elicited greater spending than water cues, and spending was moderated by the relative frequency of co-use. CONCLUSIONS: We found that combined alcohol and cigarette cues provoke more powerful craving and drug-seeking responses and, therefore, may be more motivationally potent among individuals who use multiple substances.