This project is designed to investigate associations between impulsivity and sensitivity to drug reward. Impulsivity and sensitivity to the rewarding effects of drugs are two known risk factors for drug abuse. Impulsivity is thought to have a causal role in the onset of abuse. It is a multi-faceted construct comprised of impulsive action (difficulty controlling behavior);impulsive choice (difficulty delaying gratification);impulsive attention (difficulty focusing on the task at hand);and impulsive personality (predisposition to rash action). Sensitivity to reward is also thought to influence susceptibility to use drugs, although arguments have been made that risk is related to both higher than average or lower than average sensitivity to reward. The relationship between impulsivity and reward sensitivity is poorly understood. The two constructs may independently contribute to risk for drug abuse, or they could be related to each other. There is some evidence that high impulsivity is related to low reward sensitivity, especially sensitivity to the rewarding effects of drugs. Additionally, thee is neurobiological evidence linking both impulsivity and drug reward to dopamine activity, further suggesting that the two might be related.
The aim of the current proposal is to examine sensitivity to the subjective rewarding effects of the stimulant drugs amphetamine (0-20 mg), MDMA (0-1.5 mg/kg), and caffeine (0-200 mg) in individuals high and low on each of the sub-components of impulsivity. It is hypothesized that highly impulsive individuals will exhibit a dampened subjective response compared to non-impulsive individuals. Additionally, the proposal will test if this dampened response to reward is also observable in response to sweet taste liking, a measure of non-drug reward, or if it is specific to drugs of abuse.
This project will examine relations between impulsivity and sensitivity to reward. It will examine the hypothesis that highly impulsive individuals are less sensitive to reward, especially to the rewarding subjective effects of drugs of abuse. These factors, alone or together, are believed to influence the risk for drug abuse, and the knowledge gained may help to prevent drug abuse.
|Weafer, Jessica; Gallo, David A; de Wit, Harriet (2016) Acute Effects of Alcohol on Encoding and Consolidation of Memory for Emotional Stimuli. J Stud Alcohol Drugs 77:86-94|
|Weafer, Jessica; Fillmore, Mark T (2015) Alcohol-related cues potentiate alcohol impairment of behavioral control in drinkers. Psychol Addict Behav 29:290-9|
|Weafer, Jessica; Dzemidzic, Mario; Eiler 2nd, William et al. (2015) Associations between regional brain physiology and trait impulsivity, motor inhibition, and impaired control over drinking. Psychiatry Res 233:81-7|
|Ballard, Michael E; Weafer, Jessica; Gallo, David A et al. (2015) Effects of acute methamphetamine on emotional memory formation in humans: encoding vs consolidation. PLoS One 10:e0117062|
|Weafer, Jessica; de Wit, Harriet (2014) Sex differences in impulsive action and impulsive choice. Addict Behav 39:1573-9|
|Weafer, Jessica; Mitchell, Suzanne H; de Wit, Harriet (2014) Recent Translational Findings on Impulsivity in Relation to Drug Abuse. Curr Addict Rep 1:289-300|
|Weafer, Jessica; Gallo, David A; de Wit, Harriet (2014) Amphetamine fails to alter cued recollection of emotional images: study of encoding, retrieval, and state-dependency. PLoS One 9:e90423|
|Weafer, Jessica; de Wit, Harriet (2013) Inattention, impulsive action, and subjective response to D-amphetamine. Drug Alcohol Depend 133:127-33|
|Weafer, Jessica; Baggott, Matthew J; de Wit, Harriet (2013) Test-retest reliability of behavioral measures of impulsive choice, impulsive action, and inattention. Exp Clin Psychopharmacol 21:475-81|