used as measures of impulsivity (Fillmore and Rush 2002; Green et al. 1994). Compulsivity can be defined as elements of behavior that result in perseveration of responding in the face of adverse consequences or perseveration in the face of incorrect responses in choice situations (e.g., operationally, responding for a drug or alcohol in the face of adverse consequences (Wolffgramm and Heyne 1995) or responding for a drug or alcohol on a progressive-ratio schedule of reinforcement (Walker et al. 2008)). Compulsivity is analogous to the symptoms of Substance Dependence outlined by the American Psychiatric Association: continued substance use despite knowledge of having had a persistent or recurrent physical or psychological problem and a great deal of time spent in activities necessary to obtain the substance (American Psychiatric Association 2000).
