|Current Investigations in Animal Learning
|Monday, May 30, 2016
|4:00 PM–4:50 PM
|Zurich D, Swissotel
|Area: EAB; Domain: Basic Research
|Chair: Linda Muckey (Southern Illinois University Carbondale)
|CE Instructor: Ashley Shayter, M.D.
The present set of investigations use three separate animal species to demonstrate the fundamental processes underlying human operant behavior. The continuity of species is a core assumption of the field of behavior analysis, and the use of these invertebrate and basic mammal species highlight the role of motivation both organismically and chemically, and highlight how such variables affect responsiveness to immediate environmental contingencies. The studies will show probabilistic discounting in rats, variables affecting the motivation of cockroaches, and the effects of psychoactive chemical compounds in flatworms.
|Keyword(s): Delay Discounting, Invertebrate Animals, Motivation, Rats
|Probabilistic Outcomes in Nonhuman Delay Discounting
|JAY HINNENKAMP (Utah State), Gregory J. Madden (Utah State University)
|Abstract: Delay discounting refers to the observation that the consequences of our actions lose subjective value as they are delayed in time (Madden & Johnson, 2010). To understand why delayed consequences exert less control over behavior than more immediate consequences, research has manipulated a variety of behavioral, pharmacological, and neuromodulatory factors (Gray & MacKillop, 2015). One factor that has been shown to influence human choice of smaller sooner vs. larger later consequences, but has received little attention within animal delay-discounting research, is the probability at which larger-later consequences are delivered (Mahrer, 1956). This paper will discuss the results of a between-subjects experiment that explored the effects of two different probabilistic schedules – one that delivers food with an increasing probability across time and one that delivers food with a decreasing probability across time – on rats’ impulsive choice. Furthermore, the paper will discus the relationship between rats’ interval timing during probability training and their choice within the impulsive choice assessment.
|Assessing Motivation in the Madagascar Hissing Cockroach
|ASHLEY SHAYTER (Southern Illinois University), Matthew L. Johnson (Southern Illinois University Carbondale), Mark R. Dixon (Southern Illinois University)
|Abstract: Proportion of free-feeding body weight has become an important preparation for ensuring that appropriate motivating operations are present in laboratory organisms. While well suited to work with rodents, body weight is less predictive of motivation in invertebrate organisms due to their larger proportion of weight from exoskeleton, reduced organ mass, and comparatively less fat and muscle mass. Additionally, the practice of limiting access to food to increase the value of edibles has been observed in some invertebrates to be detrimental in evoking food acquisition behaviors. This paper will present a discussion on the differences between vertebrate and invertebrate physiology as related to food-seeking behaviors and will explore methods that seek to better determine appropriate motivating operations for the Madagascar Hissing Cockroach (Gromphadorhina portenosa). Weight differences between free-feeding and deprivation will be discussed in relation to the standard proportion of body weight currently used, in addition to the amount and rates of consumption, and the utility of a free operant motivation assessment prior to conducting an experiment. Finally, a simple lever-pressing task was used in order to determine whether such assessments are better able to predict higher rates of responding. Implications of these findings and future research directions will be discussed.
|An Invertebrate Animal Model to Assess Psychoactive Properties of Tobacco Alkaloids
|BRADY J. PHELPS (South Dakota State University), Nick Thompson (South Dakota State University), Shafiqur Rahman (South Dakota State University), Heath Arens (South Dakota State University )
|Abstract: Conditioned place preference (CPP) is used to assess the abuse potential of psychoactive substances, using animals as models. Invertebrates such as the planarian flatworm are widely used in the CPP procedure. In the CPP, if animals are found to spend more time in an environment in which a putative psychoactive had been experienced, relative to settings in which a placebo had been localized, the psychoactive agent has addiction/abuse potential. Current research has highlighted that tobacco contains several compounds with unknown psychoactive properties. Given the outcome that nicotine replacement therapies have very high failure rates, it is likely that tobacco dependence is not solely based on nicotine. We will present data on the alkaloid compounds in tobacco, namely, cotinine, nornicotine, and anabasine for their psychoactive potential using the CPP animal model protocol.