Current Research

See some of our past publications

Abstracts of current projects, funded by NIDA

1. Drug responses and acute stress

We are designing and carrying out a series of studies to investigate interactions between acute stress and drugs of abuse in men and women. Stress increases drug self-administration, and alters acute responses to drugs, as shown in past studies with laboratory animals. Similarly, observations of human drug users suggest that stress may increase the susceptibility to drug use. We are investigating the effects of acute stress on acute responses to drugs and the propensity to use drugs. In some of our studies, we compare the effects of stress in men and women, in smokers and nonsmokers, and in women at different phases of the menstrual cycle. In other studies, we examine the effects of stress on responses to alcohol, methamphetamine and nicotine. Based on previous studies, we expect that stress will dampen responses to these drugs. Further, we hypothesize that the psychological effects of stress will be greater in women than men, in non-smokers than smokers, and during the luteal phase compared to the follicular phase in women. Taken together, these translational studies will provide a link between findings from animals studies and clinical observations, and will help to elucidate how stress affects drug use. The results of these studies could lead to improved methods for preventing and treating stress-related drug use.

2. Drug abuse and impulsivity

Impulsive behavior and drug use are bidirectionally linked. More impulsive individuals may be more likely to use drugs, and conversely, the use of drugs may increase impulsive behavior. Impulsivity may refer to different behaviors, including disinhibition or lapses in self-control or attention. In this project, we investigate factors that affect impulsive behavior, with the goal of eventually relating these to susceptibility to relapse to cigarette smoking. Our measures include tasks for decision-making (e.g. delay discounting), behavioral inhibition (e.g. Stop Task performance) and attention (e.g. vigilance tasks). There are many factors thought to increase impulsive behavior, and among them, we are investigating the effects of acute stress, sleep deprivation, alcohol, and, in cigarette smokers, nicotine deprivation. Among the factors thought to decrease impulsive behavior, we are studying the effects of amphetamine and bupropion. We also plan to develop a laboratory model of smoking relapse to study the role of impulsivity in relapse. Throughout these studies, we also investigate the relationships between impairments in decision-making, inhibition and attention. These studies are being conducted in parallel with other studies using rodent models of similar behaviors. The projects are designed to improve our understanding of the role of impulsive behavior in drug use.