title: Dopamine, urges to smoke, and the relative salience of drug versus non-drug reward.
abstract: When addicted individuals are exposed to drug-related stimuli, dopamine release is thought to mediate incentive salience attribution, increasing attentional bias, craving and drug seeking. It is unclear whether dopamine acts specifically on drug cues versus other rewards, and if these effects correspond with craving and other forms of cognitive bias. Here, we administered the dopamine D2/D3 agonist pramipexole (0.5 mg) to 16 tobacco smokers in a double-blind placebo-controlled crossover design. Visual fixations on smoking and money images were recorded alongside smoking urges and fluency tasks. Pramipexole attenuated a marked bias in initial orienting towards smoking relative to money but did not alter a maintained attentional bias towards smoking. Pramipexole decreased urges to smoke retrospectively after the task but not on a state scale. Fewer smoking words were generated after pramipexole but phonological and semantic fluency were preserved. Although these treatment effects did not correlate with each other, changes in initial orienting towards smoking and money were inversely related to baseline scores. In conclusion, pramipexole can reduce the salience of an addictive drug compared with other rewards and elicit corresponding changes in smoking urges and cognitive bias. These reward-specific and baseline-dependent effects support an 'inverted-U' shaped profile of dopamine in addiction.
authors: Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom tom.freeman@ucl.ac.uk.
authors: Tom P
authors: TP
authors: Freeman
authors: Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom.
authors: Ravi K
authors: RK
authors: Das
authors: Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom.
authors: Sunjeev K
authors: SK
authors: Kamboj
authors: Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom.
authors: H Valerie
authors: HV
authors: Curran
mesh_terms: D000293:Adolescent; D000328:Adult; D000339:Affect / Q000187:drug effects; D001288:Attention / Q000187:drug effects; D052160:Benzothiazoles / Q000494:pharmacology; D066249:Craving / Q000187:drug effects; D018592:Cross-Over Studies; D003463:Cues; D004298:Dopamine / Q000502:physiology*; D018491:Dopamine Agonists / Q000494:pharmacology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D009042:Motivation / Q000187:drug effects; D010775:Photic Stimulation; D000077487:Pramipexole; D012201:Reward; D012907:Smoking / Q000523:psychology*; D014029:Tobacco Use Disorder / Q000523:psychology; D055815:Young Adult
chemical_list: D052160:Benzothiazoles; D018491:Dopamine Agonists; D000077487:Pramipexole; D004298:Dopamine
keywords: attentional bias; craving; dopamine; incentive salience; reward