Dissection of appetitive conditioning. Does impulsivity play a role?

RATIONALE: It is generally assumed that cue-reactivity results from appetitive pavlovian learning. This is the reason for applying cue exposure with response prevention interventions in the treatment of substance and eating disorders. However, not all appetitive conditioned responses are equally sensitive to extinction. Additionally, impulsivity traits appear to moderate cue-reactivity. Nevertheless, there has been little research on the role of impulsivity traits in the learning of different appetitive response systems. OBJECTIVES: The purpose of the present study was (i) to replicate Van Gucht et al.'s (2010) findings, in particular, the acquisition and the differential extinction of appetitive learned responses and ii) to investigate the role of impulsivity traits in appetitive learning. METHODS: Participants (n=50) took part in a single laboratory session. Impulsivity traits (reward sensitivity, response inhibition, sensation seeking) were measured at the beginning of the session. A paradigm similar to Van Gucht et al.'s (2010) was used for the acquisition and extinction of subjective conditioned responses for milk chocolate (craving, expectancy, and liking). RESULTS: The acquisition of appetitive responses was successful. Unlike craving and liking, the extinction of expectancy was fully successful. Impulsivity traits played no role in the acquisition and extinction of appetitive conditioning. CONCLUSIONS: The results support the differential sensitivity of different appetitive response systems to extinction. The lack of findings for the role of impulsivity traits in appetitive learning shows that the question of how impulsivity affects appetitive behaviour still remains open. Theoretical and methodological issues and clinical implications of the findings are discussed.

Higher levels of trait impulsiveness and a less effective response inhibition are linked to more intense cue-elicited craving for alcohol in alcohol-dependent patients.

RATIONALE: Cue-elicited craving is a well-researched phenomenon in alcohol literature. However, not all alcohol-dependent people display the same reactivity to alcohol cues. Personality factors such as multiple impulsivity traits may be responsible for individual differences in cue reactivity by modulating its intensity. Nevertheless, there has been a scarcity of empirical studies testing this assumption in alcohol literature. OBJECTIVES: The aim of the present study was to investigate the effects of response inhibition and trait impulsiveness on cue-elicited craving for alcohol in alcohol-dependent drinkers. METHODS: Participants (n = 41) were inpatients of the private clinic U-Center, Netherlands. Alcohol exposure took place in a real bar-restaurant close to the premises of the clinic, and participants were exposed to real alcohol cues. Response inhibition was assessed with the stop-signal task and trait impulsiveness with the Barratt impulsivity scale version 11. RESULTS: The cue exposure was successful as alcohol-dependent patients experienced higher craving for alcohol when exposed to alcohol rather than to neutral cues. Additionally, both response inhibition and trait impulsiveness predicted cue-elicited craving for alcohol. Trait impulsiveness predicted both the absolute craving in the bar-restaurant and the increase in cue-elicited craving during the whole alcohol cue exposure, while response inhibition predicted only the former. CONCLUSIONS: The results clearly implicate both trait impulsiveness and response inhibition in the modulation of cue-elicited craving in alcohol dependence. Theoretical and methodological issues in the findings and their clinical implications in alcohol treatment and relapse are discussed.