Association for Behavior Analysis International

The Association for Behavior Analysis International® (ABAI) is a nonprofit membership organization with the mission to contribute to the well-being of society by developing, enhancing, and supporting the growth and vitality of the science of behavior analysis through research, education, and practice.


48th Annual Convention; Boston, MA; 2022

Event Details

Previous Page


Symposium #246
CE Offered: BACB
Recent Basic and Applied Research on Rich-Lean Transitions
Sunday, May 29, 2022
11:00 AM–12:50 PM
Meeting Level 1; Room 153A
Area: EAB/DEV; Domain: Translational
Chair: Forrest Toegel (Northern Michigan University)
Discussant: Michael Perone (West Virginia University)
CE Instructor: Forrest Toegel, Ph.D.
Abstract: Discriminable transitions from favorable to unfavorable schedules of positive reinforcement, often called rich-lean transitions, can disrupt operant behavior. The present symposium arranges four recent areas of research that further our understanding of this phenomenon. The first presentation will discuss environmental arrangements that make the schedules “rich” and “lean” and the temporal locus of pausing in research with pigeons. The second presentation investigates pharmacological methods to ameliorate the disruptions caused by rich-lean transitions with monkeys. The third presentation evaluates punitive effects of stimuli associated with lean reinforcement schedules using pigeons. The fourth presentation describes methods of incorporating the context-dependent aversive nature of rich-lean transitions to benefit individuals in the clinical environment. The symposium will conclude with a discussion led by Dr. Michael Perone. The goals of this symposium are to bring interested researchers up to speed with current research involving rich-lean transitions, highlight areas where future research could aid in our understanding of the phenomena, and describe the potential application of treatments to improve the lives of clients, their caretakers, and professionals working in clinical settings.
Instruction Level: Intermediate
Keyword(s): context-dependent aversiveness, positive reinforcement, rich-lean transitions, translational
Target Audience: Audience members should understand patterns of behavior generated by basic schedules of reinforcement and the general principle of stimulus control.
Learning Objectives: At the conclusion of this symposium, participants will be able to describe (1) aversive aspects of transitions between schedule of positive reinforcement, (2) pharmacological interventions that can affect behavioral disruptions observed in rich-lean transitions, (3) punishing effects of stimuli correlated with lean schedules of positive reinforcement, and (4) clinical implications of transitions between rich and lean reinforcement schedules.
Pausing Under Rich and Lean Fixed-Ratio Schedules: Where and When?
(Basic Research)
FORREST TOEGEL (Northern Michigan University), Cory Toegel (Northern Michigan University), Carson Yahrmarkt (Northern Michigan University), Michael Perone (West Virginia University)
Abstract: When transitions are arranged between discriminable fixed-ratio (FR) schedules that are relatively favorable (rich) and unfavorable (lean), the pause observed in the transition from the rich schedule to the lean schedule (i.e., the rich-lean transition) is extended beyond those observed in the other types of transitions. Although this finding has been well documented across various species and situations, some aspects of this phenomenon are not well understood. For example, the traditional measurement of pausing understates the disruptive effects of the rich-lean transition for some individuals. We sought to further our understanding of pausing in rich-lean transitions in two ways: by examining behavior in a new type of experimental arrangement with transitions between response targets that generate accurate and inaccurate responding and by investigating the temporal location of pausing in rich-lean transitions. We found that transitions from response targets that generate accurate responding to those that generate inaccurate responding can function as rich-lean transitions. We also identified the temporal locations of pausing in rich-lean transitions across pigeons that participated in several rich-lean projects, and make recommendations for measuring pausing by individuals for whom the typical measurement of pausing is insufficient.

Feasibility of Rich-Lean Transition Procedures With Rhesus Monkeys as an Assay for Putative Anti-Anxiety Medications

(Basic Research)
Forrest Toegel (Northern Michigan University), Cory Toegel (Northern Michigan University), James K. Rowlett (University of Mississippi Medical Center), Austin Zamarripa (Johns Hopkins University School of Medicine), SALLY L. HUSKINSON (University of Mississippi Medical Center)

Potential anti-anxiety medications are commonly assessed by measuring their “anti-conflict” effects. While these procedures have good predictive validity, there are practical limitations that may be alleviated using a different procedure. Transitions from favorable to unfavorable schedules of positive reinforcement (rich-lean transitions) disrupt operant behavior, are putatively aversive, and disruptions in rich-lean transitions can be reduced following benzodiazepine administration. We evaluated the suitability of a rich-lean transition procedure as an assay for potential anti-anxiety medications. Adult rhesus monkeys’ lever presses were reinforced using a two-component multiple schedule with equivalent fixed-ratio (FR) requirements. Components were differentially signaled by different colored cue lights. Completing one component, the lean component, produced one food pellet. Completing the other component, the rich component, produced four food pellets. Sessions consisted of 41 components arranged irregularly to produce 10 iterations of four kinds of transitions: rich-lean, rich-rich, lean-lean, and lean-rich. Consistent with previous findings, extended pausing was observed in rich-lean transitions. Acute administration of benzodiazepines (midazolam and alprazolam) and a benzodiazepine-type compound (TPA023B) selectively and dose-dependently reduced pausing in rich-lean transitions. In control conditions, acute administration of morphine selectively increased rich-lean pausing and (+)amphetamine had unsystematic effects. The suitability of rich-lean procedures as assays for putative anti-anxiety medications appears promising.


Assessing the Punishing Effects of Stimuli Associated With Rich-to-Lean Transitions

(Basic Research)
ALANNA FERGUSON (University of North Carolina Wilmington), Lillith Camp (Idaho State University ), Raymond C. Pitts (University of North Carolina Wilmington), Christine E. Hughes (University of North Carolina Wilmington)

Pigeons had experience pecking under a multiple FR FR schedule in which ratios ended in a large/rich or small/lean amount of grain. Each of the four transitions between rich and lean was signaled by a different key light color. Pigeons paused at least twice as long during the rich-to-lean transitions than during other transitions. We then established a baseline of responding on a dependent concurrent VI 20-s VI 20-s schedule. After stability was reached, we implemented punishment probes, during which one of the transition-specific stimuli was flashed contingent on responses on one of the keys according to a random-ratio schedule. We examined potential conditioned punishment (e.g., rich-to-lean and lean-to-lean stimuli) or reinforcement (e.g., lean-to-rich and rich-to-rich) effects. Results could inform clinical practice in that it may demonstrate how advance notice or prompts that remind individuals to do work may function aversively.

Practical Implications of the Conceptual Understanding of Transitions
(Applied Research)
SOPHIA MA (Queens College), Joshua Jessel (Queens College)
Abstract: A child is likely to experience transitions between rich and lean reinforcement on a daily basis. These transitions could evoke problem behavior ranging from dawdling or off-task behavior to severe aggression or self-injurious behavior, especially for those diagnosed with autism. On the other hand, transitions can also be systematically arranged by clinicians as a form of intervention for improving targeted repertoires. In this talk we will discuss these juxtaposed practical implications of rich-to-lean transitions being the problem in need of solving to transitions being the solution. Our research in transitions has been designed to support service delivery by developing (a) assessments that can be conducted to determine level of difficulty with rich-to-lean transitions, (b) interventions including unpredictable and probabilistic reinforcement for reducing problem behavior evoked by transitions, and (c) error-correction procedures that utilize transitions to improve performance with discrete-trial instructions. We intend for this talk to be an intervention-driven activity for audience members working with children diagnosed with autism or other related developmental disabilities.



Back to Top
Modifed by Eddie Soh