Central Research Hypotheses


  • The central research hypothesis of the Center is that impulsivity is a multi-dimensional construct that can be parceled into four separate facets: (1) Urgency; (2) lack of Premeditation; (3) lack of Perseverance; and (4) Sensation Seeking (Whiteside & Lynam, Pers Ind Diff 11:210-217, 2001); and that each of these biologically-based facets confer risk for drug abuse. This overall hypothesis is being evaluated in 3 integrated research projects as outlined below.
  • 1. Project 1 is using a rat model to investigate the neurobiological basis of urgency and sensation seeking. This project will determine the relation of these facets of impulsivity to different phases of drug self-administration, as well as to determine which facet best predicts the ability of non-drug reinforcers to reduce use.
  • 2. Project 2 is concentrating on impulsivity in young adult college students to determine the brain regions involved using fMRI and determine which facets of impulsivity are associated with escalation of marijuana and/or tobacco use. Parallel laboratory-based studies will determine the reinforcing effects of marijuana and tobacco among escalators and non-escalators, with alcohol priming being used to promote disinhibition in the laboratory.
  • 3. Project 3 will concentrate on urgency in young adult college students to determine what brain regions are involved and how this facet operates compared to sensation seeking when affect is altered by interpersonal interactions in the laboratory or in the field. This project also will evaluate a mindfulness preventive intervention trial that targets individuals high in urgency.