|Behavioral Variability: Reinforcement and Induction|
|Saturday, May 26, 2018|
|11:00 AM–12:50 PM |
|Marriott Marquis, San Diego Ballroom C|
|Area: EAB/PCH; Domain: Translational|
|Chair: Allen Neuringer (Reed College)|
|Discussant: Allen Neuringer (Reed College)|
Acquisition of operant behavior depends on selection from behavioral variations. As discussed by Stahlman, variations result from two main sources, direct reinforcement of variability itself and induction of variability resulting from such sources as Pavlovian relationships and extinction. Nergaard & Holth describe a novel procedure (with rats) and question the very possibility of reinforced or "operant" variability. They attribute observed variability to cycles of reinforcement and extinction of individual responses. Quite differently, Galizio, Haynes, Frye & Odum continue an extensive line of research showing that response variability is a behavioral dimension controlled by contingencies in many ways analogously to other such operant dimensions as response rate and force. They explore (with pigeons) spontaneous recovery of previously reinforced variable responding. Abreu-Rodrigues and Carmona extend research on how variability contingencies influence preferences. They explore (with pigeons) choices for different run length of varying sequences. This symposium provides innovative research and interpretations of response variability with diverse theoretical views from diverse locales -- Brazil, Norway and the US. Neuringer, as discussant, will attempt to relate the four presentations to additional basic operant-variability research and its application in education and treatment of autism.
|Instruction Level: Intermediate|
|Keyword(s): Extinction, Reinforced variability, Spontaneous recovery, Variation-Selection|
|Spontaneous Recovery of Reinforced Behavioral Variability|
|ANNIE GALIZIO (Utah State University), Jeremy Haynes (Utah State University), Charles Casey Joel Frye (Utah State University), Amy Odum (Utah State University)|
|Abstract: Reinforced behavioral variability is adaptive and has been shown to be susceptible to relapse in the form of reinstatement, resurgence, and rapid reacquisition. In the present study, we examined spontaneous recovery of reinforced behavioral variability in pigeons. Twelve pigeons emitted four-peck sequences across two keys and responded in a two-component multiple schedule. In the Vary component, pigeons earned food for emitting sequences that satisfied a lag 8 schedule of reinforcement, i.e., a sequence produced food only if it differed from the previous eight sequences emitted. In the Yoke component, reinforcement was delivered probabilistically, such that reinforcement rates in both components were matched. Next, responding in both components was placed on extinction. Following extinction, pigeons experienced a rest period in which sessions were not run. Finally, we tested for spontaneous recovery by resuming extinction sessions. An increase in variable responding in the Vary component during testing would be indicative of spontaneous recovery of reinforced behavioral variability. This finding would have implications for interventions designed to increase or decrease behavioral variability in clinical populations.|
Recent Challenges to the View That Variability can be Directly Reinforced
|SIV KRISTIN NERGAARD (Oslo and Akershus University College of Applied Sciences), Per Holth (Oslo and Akershus University College of Applied Sciences)|
Research by Neuringer and colleagues has reliably demonstrated that behavioral variability increases when reinforcement is contingent on it. An alternative summary of the contingencies that typically prevail in variability experiments is that several responses cycle between reinforcement and extinction. The current Experiment 1 tested this by making reinforcement contingent upon predetermined but shifting responses. Resulting U values were similar to those obtained in comparable lag schedules. Second, the details of what happens when reinforcement is contingent on variable responding may be more transparent when the descriptive operant class consists of responding to several different operanda rather than of different sequences of responses on two operanda. In Experiment 2, we also modified the lag n schedule so that reinforcement was contingent on the occurrence of a response to an operandum that differed from the n previously operated operanda rather than just the n previous responses. The results showed that (1) the rats only emitted as many different responses as the lag schedule required, (2) when the lag increased and, thus, required a response to an additional operandum, such an additional response emerged, and next (3) rather than demonstrating reinforced variability, the rats fairly consistently repeated the last reinforced response.
Numerosity Discrimination: Does it Affect Choice Under Variation Contingencies?
|JOSELE ABREU RODRIGUES (Universidade de Brasilia), Lucas Carmona (Universidade de Brasília)|
Choice between differing varying contingencies is affected by the variation requirement as well as by the cost of responding (i.e. switching between operanda). The present study investigated whether such choices would also be affected by within-sequence discriminative control. This possibility is supported by numerosity studies which show an inverse relation between sequence accuracy and run length, i.e., number of responses to be emitted on one operandum before switching to the other. Pigeons were exposed to a pre-training phase in which control by numerosity was established. By the end of this phase, the animals had to emit 10-response sequences according to a multiple schedule. To be reinforced, the sequence had to differ from the previous two correct ones and contain run lengths of 1 to 4 responses (Max 4-Lag 2 component) or 6 to 9 responses (Min 6-Lag 2 component). Accuracy was close to 50% in both components. Next, a concurrent-chain schedule in which the Max 4-Lag 2 and Min 6-Lag 2 contingencies operated in the terminal links. Preference for the shorter run length was observed for the pigeon that is already in this phase, despite equal reinforcer probabilities across terminal links, suggesting that discriminative control by numerosity affects choice.
|The Sources of Adaptive Behavioral Variation: Simplifying the Problem|
|WILLIAM DAVID STAHLMAN (University of Mary Washington)|
|Abstract: Variation is not merely important for the production of adaptive phenotypes, but fundamentally necessary to the products of any evolutionary system. This simple fact illuminates a major discrepancy between modern psychology and behavior analysis. Though much of contemporary work in psychology diminishes or disregards the need to account for variation in individuals, a behavior analytic perspective sees such variation as being a primary thing to be explained. Empirical work suggests at least two means by which behavioral variation may be controlled; one manner is by virtue of the consequences of varying behavior (i.e., operant variation), while another is by virtue of the stimulus control exerted antecedently to the emission of behavior (i.e., respondent variation). I discuss this literature in the context of an evolutionary selectionist framework and present important parallels in the functions of variation at different levels of selection. All important effects may be folded into what I have termed a behavioral evolutionary synthesis, which characterizes organismal behavior as the primary unit of selection in evolution. I contend this framework represents an important simplification of thought in behavioral science.|