in responding were due to positive or nega - NCBI

JOURNAL OF APPLIED BEHAVIOR ANALYSIS

1996, 292 247-250

NUMBER2

(SUMMER 1996)

ANALYSIS OF FREE- TIME CONTINGENCIES AS POSITIVE VERSUS NEGATIVE REINFORCEMENT JENNIFER R. ZARCONE, WAYNE W. FISHER, AND CATHLEEN C. PIAZZA THE KENNEDY KRIEGER INSTITUTE AND JOHNS HOPKINS UNIVERSITY SCHOOL OF MEDICINE

Providing a short break contingent on completed work may increase responding through positive reinforcement (e.g., access to preferred activities) or negative reinforcement (e.g., escape from work). In this investigation, three analyses conducted with a boy with profound mental retardation showed that (a) a 20-s break increased responding more than a positive reinforcer (cola) did, and (b) the reinforcing effects of a 20-s break were affected by the availability of positive reinforcers during the break. DESCRIPTORS: behavioral assessment, negative reinforcement, positive reinforcement, reinforcer assessment, free-time contingencies

Research on the use of free-time contingencies has not evaluated whether changes in responding were due to positive or negative reinforcement (Iwata, 1987). For example, Osborne (1969) used free time as reinforcement for in-seat behavior. However, it was unclear whether behavior increased as a result of negative reinforcement in the form of escape from work or positive reinforcement in the form of access to preferred activities. In the present study, a series of analyses were conducted to determine whether positive reinforcement or negative reinforcement was more effective in increasing task behavior. In separate phases, we evaluated (a) the effects of a putative negative reinforcer (a 20-s break from work) compared to the effects of a positive reinforcer (cola) on a free-operant response, (b) the effects of a break with and without access to preferred stimuli, and (c) the effects The authors thank Jackie Nguyen and Jennifer Cannon for their assistance in this project. This investigation was supported in part by Grant MCJ249149-02 from the Maternal and Child Health Service of the U.S. Department of Health and Human Servlces. Requests for reprints should be sent to Wayne W. Fisher, Neurobehavioral Unit, The Kennedy Krieger Institute, 707 N. Broadway, Baltimore, Maryland 21205.

of a break with access to preferred stimuli in the treatment of noncompliance. METHOD Ray was a 10-year-old boy who had been diagnosed with autism and profound mental retardation. All sessions lasted 5 min and were conducted either in the living area of a hospital unit or in a treatment room (3 m by 3 m). Trained observers using laptop computers recorded the rate of cup stacking (Phases 1 and 2) and compliance with academic tasks (Phase 3). All inappropriate or off-task behaviors were ignored. Time spent consuming reinforcement was removed from the overall session time to calculate rates of the dependent measures in all phases. Interobserver agreement was assessed during 48%, 76%, and 43% of sessions, and exact agreement coefficients averaged 96%, 95%, and 96% for the three phases, respectively. A combination reversal-multielement design was used for Phases 1 and 2, and a multiple baseline across tasks was used for Phase 3. Prior to Phase 1, cola was identified as a highly preferred reinforcer using methods described by Fisher et al. (1992). During baseline of Phase 1, Ray was seated in a cor-

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ner behind a table that prevented egress, and either red or blue cups were placed before him on the table. There were no consequences for stacking cups; the cups were simply unstacked again by the therapist. The reinforcement conditions in Phase 1 were identical to baseline, except that stacking red cups resulted in access to 0.5 oz of cola at the work table in one condition, and stacking blue cups resulted in a 20-s break in the other condition (Ray could leave the work table). Cup stacking was reinforced on a continuous schedule. Before each session, the contingency in effect was described to and modeled for Ray. Although attention and other highly preferred items were unavailable during the break in Phase 1, Ray often walked around the room, looked at others or out of the window, or lay on his bed. If these activities were preferred stimuli for Ray, then the effects of the 20-s break may have been attributed to positive reinforcement. We examined this possibility in Phase 2 by minimizing access to preferred stimuli during breaks in one condition (i.e., break only) and providing access to highly preferred stimuli in the other (i.e., break with preferred stimuli identified during the preference assessment or the previous phase). Sessions were conducted in a treatment room, which was empty except for the table and task materials. Baseline was identical to the baseline in Phase 1 except that only white cups were used. During reinforcement, procedures were identical to baseline except that (a) in the break-only condition, cup stacking produced a 20-s break (Ray could leave the table but remained in the room with no interaction), and (b) in the break with preferred stimuli, cup stacking produced a 20s break with access to preferred stimuli (Ray could leave the room, clap and dance to music with the therapist, lie on his bed, or look out of the window). Based on the results of Phase 2, a break

with access to preferred stimuli was used in Phase 3 contingent on compliance with academic or occupational work tasks (peg placement, paper cutting, and stapling). The tasks were presented in separate sessions. During baseline, the therapist prompted Ray to complete the task for that session using a sequence of verbal, gestural, and physical prompts every 10 s until the task was completed. Compliance (i.e., completion of the task prior to the physical prompt) resulted in praise. During reinforcement, each occurrence of compliance produced a 20-s break with preferred stimuli. The schedules were subsequently faded to variable-ratio (VR) 2 and then VR 5. RESULTS AND DISCUSSION The results of Phase 1 are presented in Figure 1, in which the effects of a positive reinforcer (cola) with a negative reinforcer (20-s break) on the rate of a free-operant task are compared. Results showed that Ray stacked cups at a higher rate to gain access to the 20-s break. However, it was unclear whether the reinforcing event was escape from work (negative reinforcement) or access to the activities available during the break (positive reinforcement). The results of Phase 2 are also presented in Figure 1. Notable increases in cup stacking over baseline levels occurred when Ray was given access to preferred activities during the break, but increases did not occur when a break from work was the only consequence. During Phase 3, when a break with preferred stimuli was implemented contingent upon compliance with each of the three occupational tasks, the mean percentages of compliance increased markedly (from 13% to 91% for peg placement, 15% to 94% for paper cutting, and 28% to 93% for stapling). Results of these analyses support the con-

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func- contingent breaks from instructional tasks as tion either positive negative reinforce- a means of examining the effects of negative ment (Iwata, 1987; Osborne, 1969). In the reinforcement on aberrant behavior. These current investigation, the reinforcing effects analyses are often conducted in classrooms of the break contingency were primarily a or other environments in which preferred function of positive reinforcement rather stimuli may be available during the break, than negative reinforcement. In addition, and the client may be responding to obtain these results suggest that it may be impor- these stimuli (i.e., positive reinforcement) tant to consider both the activity that is ter- rather than to terminate the task (i.e., negminated and the activity that is initiated ative reinforcement). In such cases, prewhen evaluating the reinforcing effects of scribed treatments (e.g., modifying the task breaks. From a clinical standpoint, when to make it less aversive) may fail if the abbreaks are used to reinforce compliance or errant behavior is maintained by access to other behaviors, it may be useful to provide preferred stimuli (i.e., positive reinforceaccess to highly preferred activities during ment) during the break. Future investigators the break, thereby capitalizing on the effects may wish to evaluate the combined effects of both positive and negative reinforcement. of positive and negative reinforcement in the These results also may have implications assessment and treatment of aberrant behavfor functional analysis procedures that use ior. tention that free time (or a break) as

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JENNIFER R. ZARCONE et al. REFERENCES

Fisher, W., Piazza, C. C., Bowman, L. G., Hagopian, L. P., Owens, J. C., & Slevin, I. (1992). A comparison of two approaches for identifying reinforcers for persons with severe to profound disabilities. Journal of Applied Behavior Analysis, 25, 491-498. Iwata, B. A. (1987). Negative reinforcement in ap-

plied settings: An emerging technology. Journal of Applied Behavior Analysis, 20, 361-378. Osborne, J. G. (1969). Free-time as a reinforcer in the management of classroom behavior. Journal of Applied Behavior Analysis, 2, 113-118.

Received June 5, 1995 Final acceptance December 1, 1995 Action Editor, Brian A. Iwata