Token Reinforcement: A strangely under-explored and under-applied domain in behavior analysis

Token Reinforcement: A strangely under-explored and under-applied domain in behavior analysis
Ron Allen and Jeff Kupfer
Simmons University (Boston) and University of Colorado (Denver)

Over the years there have been gentle debates concerning the event that signaled the birth of Applied Behavior Analysis (ABA). Some suggest the demonstration by Fuller (1949) of the operant conditioning of the arm movement of a man with profound developmental disabilities was first. Others suggest Ayllon & Michaels’ (1959) documentation of the effects of behavior change procedures with patients in a mental health facility. An easy case can be made for the 1968 debut publication of the Journal of Applied Behavior Analysis, including the seminal and defining article by Baer, Wolf, & Risley Some Current Dimensions of Applied Behavior Analysis. However, another strong candidate could be the publication in 1968 of Ayllon & Azrin’s The Token Economy: A motivational system for therapy and rehabilitation detailing the use of token reinforcement programming to modify challenging behavior of patients diagnosed with chronic psychosis at Anna State Hospital in Illinois.

A token is an object or symbol that is exchanged for goods or services (Hackenberg, 2009). A token economy is defined as a behavior change system consisting of a list of target behaviors, with tokens (points or small objects) participants can earn for emitting the target behaviors, and a menu of back-up reinforcers (i.e., preferred items, activities, or privileges for which participants exchange earned tokens (Cooper, Heron, & Heward, 2020 p.801). In the Token Economy developed by Ayllon and Azrin the behaviors of long-term psychiatric patients (“psychotics”) were modified by contingent token presentation later exchanged for back-up reinforcers. These behaviors including attendance in activities, self-care and daily living skills, vocational tasks, and more were greatly enhanced for the majority of the patient participants. Reversal designs, including removal of token presentations or presentations of unpaired tokens, demonstrated functional relations between responding and contingent tokens, suggesting a conditioned reinforcement process.

Over the years, token reinforcement programs have become near-universal in the toolbox of behavior analytic Service Delivery. However, despite the universal adoption of token reinforcement technology in our service delivery, research into the processes active in token reinforcement, as well as the employment of token reinforcement procedures in the analyses of basic behavioral processes (e.g., conditioned reinforcement-including generalized reinforcers, behavioral economics, scaling positive and negative reinforcers, delay discounting, functional units of behavior, and more) has been largely unexplored (Hackenberg, 2009, 2018).

In 2009, Hackenberg summarized both historic and contemporary laboratory research on token reinforcement beginning in work with chimpanzees at the Yerkes Primate Center (Cowles, 1937; Kelleher, 1956, 1957; Wolf, 1936) earning coin-like tokens exchangeable for food. Laboratory analyses by Malagodi and colleagues continued in the 1960-70’s with rats lever pressing for marbles exchangeable for food (e.g., Malagodi, 1967 a, b, c; Malagodi, E. F., Webbe, F. M., & Waddell, T. R. (1975); Waddell, Leander, Webbe, & Malagodi, (1972); Webbe & Malagodi, 1978). More contemporaneously, Hackenberg and colleagues have documented keypecking by pigeons reinforced by illumination of chamber stimulus lamps subsequently exchangeable for food or water presentation (e.g., DeFulio, Yankelevitz, Bullock & Hackenberg, 2014; Foster, Hackenberg, Vaidya, (2001) Jackson & Hackenberg, 1996; Pietras & Hackenberg, 2005; Yankelevitz, Bullock, & Hackenberg, 2008). Together these studies have not only demonstrated the reinforcing effects of stimuli exchangeable for primary reinforcement, but also have illuminated properties shared by token reinforcement contingencies and other sequentially arranged contingencies (i.e., chained schedules and second-order schedules. Hackenberg, 2009).

Token reinforcement programs can be conceptualized as three inter-related schedule contingencies; the token-production schedule (what behaviors result in token presentation), the exchange-production schedule (what behaviors and/or time criterion are required to produce the exchange opportunity), and the token exchange schedule (the schedule governing the exchange or purchasing of back-up reinforcers by tokens). As alluded to above, control and manipulation of these three schedules can allow for the exploration of a variety of behavioral process, but such explorations have been limited. However, a greater limitation may be the paucity of translational research dedicated to token reinforcement given its pervasive presence in behavior analytic service delivery. Translational dialog and research between the experimental and applied research components of behavior analysis, as described by Hackenberg (2018) would seem long-overdue.

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