|Examining the Role of State vs. Trait Variables on Delay Discounting Across Human and Animal Subjects
|Sunday, May 24, 2020
|9:00 AM–9:50 AM
|Marriott Marquis, Level M2, Marquis Ballroom 1/2
|Area: EAB/VRB; Domain: Translational
|Chair: Luis Rodriguez (Idaho State University)
Delay discounting, a behavioral measure of impulsive choice, is the decrease in subjective value of a reward as delay to its receipt increases. Steeper delay discounting has been associated with various health outcomes such as substance use, obesity, problematic gambling, risky sex, etc., and may be an underlying mechanism in the development and maintenance of these maladaptive health behaviors. The discounting literature has as abundance of evidence suggesting that an individual’s sensitivity to delayed outcomes is related to both state and trait properties. The purpose of this symposium is to present new data detailing effects of state and trait properties on delay discounting across rats and humans. The speakers will present data revealing the cross-species trait-like behaviors in the discounting of differing outcomes, the changes in discounting that can be observed across the lifespan and pubertal development, and the role verbal stimuli play in influencing discounting states. These results highlight the similarities and differences in trait and state like factors between non-humans and human subjects.
|Instruction Level: Intermediate
|Keyword(s): choice, delay discounting, framing effects, state trait
|Delay Discounting of Food and Water in Rats Shows Trait Characteristics
|CAROLINE TOWSE (Utah State University), Jeremy Haynes (Utah State University), Annie Galizio (Utah State University), Charles Casey Joel Frye (Utah State University), Amy Odum (Utah State University)
|Abstract: Delay discounting is the tendency for the subjective value of a reward to decrease as the time until receipt increases. It is an important predictor of maladaptive behavior such as substance abuse, problematic gambling, and risky sexual behaviors. Discounting of delayed outcomes appears to have both state and trait properties in humans. State manipulations of discounting (e.g., outcome framing) demonstrate that discounting can be affected by relatively short-term manipulations; however, discounting is also stable within individuals. The present study focuses on examining the trait properties of delay discounting in non-human animals. Long-Evans rats completed a discounting task from approximately 85 post-natal days to 365 days of age with two different commodities, food and water, that alternated daily. Results indicate discounting of water is significantly and positively correlated with discounting of food. Furthermore, delay discounting decreased overall across time. These results replicate prior research with humans, providing evidence of trait-level discounting in rats.
|Relation Between Age, Puberty, and Obesity in Food Delay Discounting
|YAEEUN LEE (Idaho State University), Erin B. Rasmussen (Idaho State University)
|Abstract: No current study has investigated the degree to which age is related to food delay discounting (DD). Puberty, a time at which eating patterns tends to shift as food intake increases and maintains to accompany growth spurts, may predict a change in food discounting. The present study examined the relations between DD for food and age, as well as the variables of obesity and puberty statuses, as measured by physician-report. Data from an ongoing study with 25 children and 86 adult participants were examined using regression analyses. There were no main effects of age, and puberty and obesity statuses (e.g., body mass index, percent body fat) on food discounting. However, regression analyses revealed magnitude effects (smaller magnitudes were discounted more steeply) with age identified as a significant predictor for medium (p=0.001) and large (p=0.005) magnitudes of food DD when controlling for puberty and obesity statuses.
|The Effects of Obligatory and Preferential Frames on Delay Discounting
|Laura Barcelos Nomicos (University of Nevada, Reno), KENNETH W. JACOBS (University of Nevada, Reno), Matt Locey (University of Nevada, Reno)
|Abstract: Human decision-making is partly determined by the verbal stimuli involved in a choice. Verbal stimuli that may be particularly relevant to human decision-making are the words “should” and “like”, whereby “should” is presumably associated with what one ought to choose and “like” is presumably associated with what one prefers to choose. The purpose of the current investigation was to test the potential effects of “should” and “like” on decisions in a monetary delay discounting task. Eighty-three participants were recruited from Amazon’s Mechanical Turk and were randomly assigned to a sequence of two conditions—Should and Like—in a repeated measures experimental design. Based on condition assignment, the questions “Which should you choose?” and “Which would you like to choose?” appeared above each monetary option and its respective delay. Overall, participants demonstrated significantly lower levels of discounting in the Should condition when compared to the Like condition. The implication is that questions using the words “should” and “like” may constitute separate classes of frames referred to as obligatory and preferential respectively. The current presentation will explore that implication along with the data that indicate a particularly interesting sequence effect: Participants discount less in the Should condition when they are asked “Which would you like to choose?” first.