Choice impulsivity: Definitions, measurement issues, and clinical implications.

Abstract

Background Impulsivity critically relates to many psychiatric disorders. Given the multi-faceted construct that impulsivity represents, defining core aspects of impulsivity is vital for the assessment and understanding of clinical conditions. Choice impulsivity (CI), involving the preferential selection of smaller sooner rewards over larger later rewards, represents one important type of impulsivity. Method The International Society for Research on Impulsivity (InSRI) convened to discuss the definition and assessment of CI and provide recommendations regarding measurement across species. Results Commonly used preclinical and clinical CI behavioral tasks are described, and considerations for each task are provided to guide CI task selection. Differences in assessment of CI (self-report, behavioral) and calculating CI indices (e.g., area-under-the-curve, indifference point, steepness of discounting curve) are discussed along with properties of specific behavioral tasks used in preclinical and clinical settings. Conclusions The InSRI group recommends inclusion of measures of CI in human studies examining impulsivity. Animal studies examining impulsivity should also include assessments of CI and these measures should be harmonized in accordance with human studies of the disorders being modeled in the preclinical investigations. The choice of specific CI measures to be included should be based on the goals of the study and existing preclinical and clinical literature using established CI measures.

The NIH Science of Behavior Change Program: Transforming the science through a focus on mechanisms of change

“…Given the wide range of sub-components implicated, it has proven difficult to measure self-regulation consistently in the laboratory, in clinical trials, or in large scale observational studies (Duckworth & Kern, 2011; Hamilton et al, 2015; Morean et al, 2014). Work needs to be done to determine the most appropriate assessments for behavior change science.…”

Lorcaserin and CP-809101 reduce motor impulsivity and reinstatement of food seeking behavior in male rats: Implications for understanding the anti-obesity property of 5-HT2C receptor agonists

“…The primary measures were the percentage choice of large reward as a function of delay, the latency to respond on either lever, nose pokes into the magazine well during the delay period, and the number of choice trials completed and missed (40 choice trials in total). In addition, the area under the discounting curve (AUC) was also calculated to provide an unbiased quantitative assessment of delay discounting over all the delays (see Myerson et al 2001;Hamilton et al 2015). Once these performance measures were stable the effect of drug treatment on performance was measured.…”

“…Impulsive action (behavioural disinhibition) is characterized by acting prematurely, or failing to inhibit responding, and is often measured as premature responding on the 5-choice serial reaction time task (5-CSRTT) (Robbins 2002) or as inappropriate responding during the NoGo phase of a Go-NoGo schedule (Harrison et al 1999;Dalley et al 2011). Impulsive choice is characterized as the choice of a small, immediate reward or over a larger, but delayed alternative; it is commonly measured using a delay-discounting task (Evenden and Ryan 1996;Cardinal et al 2000;Winstanley 2011;Hamilton et al 2015). To date, investigations of 5-HT 2C receptor agonists on impulsive behaviour have essentially been limited to the 5-CSRTT, where Ro 60-0175 and WAY 163909 have been reported to reduce premature responding (Fletcher et al 2007;Quarta et al 2007;Navarra et al 2008).…”

Decline of prefrontal cortical-mediated executive functions but attenuated delay discounting in aged Fischer 344 × brown Norway hybrid rats

“…Cognitive flexibility is not as well characterized in the context of intertemporal choice; however, both an exaggerated ability to delay gratification and behavioral inflexibility are associated with the eating disorder anorexia nervosa (Steinglass et al, 2012; Tchanturia et al, 2004), suggesting the possibility that such relationships may exist. In addition, tasks used to study intertemporal choice in rodents often incorporate a block design, which places demands on cognitive flexibility as response contingencies shift over the course of test sessions (Hamilton et al, 2015). As our laboratory has reported both an enhanced ability to delay gratification (Simon et al, 2010) and impaired cognitive flexibility (Beas et al, 2017, 2013) in aged rats, it is reasonable to hypothesize that cognitive inflexibility in aged subjects may in part mediate age-associated differences in intertemporal choice using the block task design (Breton et al, 2015).…”