Substance use is associated with reduced devaluation sensitivity

Abstract

Substance use has been linked to impairments in reward processing and decision-making, yet empirical research on the relationship between substance use and devaluation of reward in humans is limited. We report findings from two studies that tested whether individual differences in substance use behavior predicted reward learning strategies and devaluation sensitivity in a nonclinical sample. Participants in Experiment 1 (N = 66) and Experiment 2 (N = 91) completed subscales of the Externalizing Spectrum Inventory and then performed a two-stage reinforcement learning task that included a devaluation procedure. Spontaneous eye blink rate was used as an indirect proxy for dopamine functioning. In Experiment 1, correlational analysis revealed a negative relationship between substance use and devaluation sensitivity. In Experiment 2, regression modeling revealed that while spontaneous eyeblink rate moderated the relationship between substance use and reward learning strategies, substance use alone was related to devaluation sensitivity. These results suggest that once reward-action associations are established during reinforcement learning, substance use predicted reduced sensitivity to devaluation independently of variation in eyeblink rate. Thus, substance use is not only related to increased habit formation but also to difficulty disengaging from learned habits. Implications for the role of the dopaminergic system in habitual responding in individuals with substance use problems are discussed.

Addiction is driven by excessive goal-directed drug choice under negative affect: translational critique of habit and compulsion theory

“…By contrast, habitual participants will choose the same first-stage stimulus as they chose on the previous trial because that previous trial was reinforced, even though this choice gives only a 30% chance of producing the same second-stage pair as the previous trial. In short, the task measures whether participants make choices using knowledge of the transitional structure between stages, or simply repeat choices that paid off in the previous trial [229,233,[278][279][280][281]. Shock punishment of self-administration in laboratory animals: Animals are first trained on a drug self-administration schedule (or seeking-taking chain, where an initial response is required to access the self-administration lever).…”

Habit, choice, and addiction

“…In humans, the 2-step task (box 2) was developed to estimate individual reliance on model-based and model-free control [48,[52][53][54] and is more suitable to measure the relative strength of both systems (but see [101]). Using this procedure, several studies have shown correlation between drug use and the strength of model-based control [102,103]. Recent adaptation of this task in rodents [104][105][106] will provide further information about the relative contribution of model-based and model-free systems in animal models of addiction [107].…”

Alcohol Sensitivity as an Endophenotype of Alcohol Use Disorder: Exploring Its Translational Utility between Rodents and Humans

“…The degree to which the flavored solution is then avoided is interpreted as evidence of the aversive actions of ethanol. CTA is distinct from devaluation procedures, which are used to assess reward disengagement that results from the revision of reward value information and inhibition of previously learned responses [ 226 , 227 ]. Numerous rodent studies have consistently demonstrated large genetic differences in sensitivity to CTA [ 228 , 229 , 230 , 231 ], but it is important to note that a high enough dose of ethanol paired with the flavored solution will result in CTA regardless of genotype.…”