title: Acquisition of Conditioning between Methamphetamine and Cues in Healthy Humans.
abstract: Environmental stimuli repeatedly paired with drugs of abuse can elicit conditioned responses that are thought to promote future drug seeking. We recently showed that healthy volunteers acquired conditioned responses to auditory and visual stimuli after just two pairings with methamphetamine (MA, 20 mg, oral). This study extended these findings by systematically varying the number of drug-stimuli pairings. We expected that more pairings would result in stronger conditioning. Three groups of healthy adults were randomly assigned to receive 1, 2 or 4 pairings (Groups P1, P2 and P4, Ns = 13, 16, 16, respectively) of an auditory-visual stimulus with MA, and another stimulus with placebo (PBO). Drug-cue pairings were administered in an alternating, counterbalanced order, under double-blind conditions, during 4 hr sessions. MA produced prototypic subjective effects (mood, ratings of drug effects) and alterations in physiology (heart rate, blood pressure). Although subjects did not exhibit increased behavioral preference for, or emotional reactivity to, the MA-paired cue after conditioning, they did exhibit an increase in attentional bias (initial gaze) toward the drug-paired stimulus. Further, subjects who had four pairings reported "liking" the MA-paired cue more than the PBO cue after conditioning. Thus, the number of drug-stimulus pairings, varying from one to four, had only modest effects on the strength of conditioned responses. Further studies investigating the parameters under which drug conditioning occurs will help to identify risk factors for developing drug abuse, and provide new treatment strategies.
authors.affiliation: Department of Psychiatry and Behavioral Neuroscience, University of Chicago, 5841 S. Maryland Ave, MC3077, Chicago, IL 60637, United States of America.
authors.forename: Joel S
authors.identifier: http://orcid.org/0000-0003-0526-5713
authors.initials: JS
authors.lastname: Cavallo
authors.affiliation: Center for Social and Affective Neuroscience, Department of Clinical and Experimental Medicine, Linkӧping University, SE 58183, Linkӧping, Sweden.
authors.forename: Leah M
authors.initials: LM
authors.lastname: Mayo
authors.affiliation: Department of Psychiatry and Behavioral Neuroscience, University of Chicago, 5841 S. Maryland Ave, MC3077, Chicago, IL 60637, United States of America.
authors.forename: Harriet
authors.initials: H
authors.lastname: de Wit
mesh_terms: D000161:Acoustic Stimulation; D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000339:Affect / Q000187:drug effects; D000070379:Attentional Bias / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D003214:Conditioning, Classical; D003463:Cues; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008694:Methamphetamine / Q000008:administration & dosage*; D010775:Photic Stimulation; D019966:Substance-Related Disorders / Q000503:physiopathology* / Q000523:psychology
chemical_list: D008694:Methamphetamine