title: Introduction: motivation, drug abuse, and 50 years of theoretical and empirical inquiry.
authors.affiliation: University of Nebraska-Lincoln, USA.
authors.forename: Rick A
authors.initials: RA
authors.lastname: Bevins
authors.forename: Michael T
authors.initials: MT
authors.lastname: Bardo
mesh_terms: D016739:Behavior, Addictive / Q000503:physiopathology / Q000523:psychology*; D006801:Humans; D009042:Motivation; D011603:Psychophysiology; D019966:Substance-Related Disorders / Q000503:physiopathology / Q000523:psychology*