False-positive maintenance of self-injurious behavior by access to tangible reinforcers.

Results of a functional analysis indicated that the hand mouthing of a woman with developmental disabilities was maintained by multiple sources of control (sensory stimulation and access to a leisure item). Further assessment revealed that access to several other items also produced high rates of hand mouthing. However, direct observation conducted in the woman's home indicated that none of these items was delivered contingent upon hand mouthing. When the consequence observed most frequently in the home was incorporated into the functional analysis, rates of hand mouthing were no higher than they were during an alone condition. We concluded that hand mouthing, although maintained by automatic reinforcement, was also susceptible to social contingencies when exposed to them during assessment, thereby producing a partially false-positive outcome.     

Basing the treatment of stereotypic and self-injurious behaviors on hypotheses of their causes.

Stereotypic and self-injurious behaviors are common forms of maladaptive responding demonstrated by severely handicapped persons. Various review papers suggest that no single treatment procedure is universally effective. Although there may be many reasons for this finding, one could be that people engage in these behaviors for various reasons, and that procedures that are incompatible with the cause of the behavior are unlikely to be effective. These studies also suggest many hypotheses for the development and maintenance of these behaviors, three of which are the self-stimulation, positive reinforcement, and negative reinforcement hypotheses. The purpose of this paper was to determine whether one of these hypotheses could be matched to the cause of the behavior and used as an effective treatment procedure. We therefore compared one hypothesis with one other for 3 subjects in a three-phase study. During baseline, data were taken in two classrooms for each subject, and a judgement was made about the hypothesis most likely to be related to the cause of the behavior. During the second phase, a treatment based on that hypothesis was used in one classroom, and a treatment based on another hypothesis was used in the second classroom. During the third phase, the treatment that was most effective in the second phase was used in both classrooms. Results showed that a successful treatment program can be developed on an hypothesis of why the behavior occurred during baseline. Results are discussed in terms of supporting the argument that treatment programs should be based on a functional analysis of the behavior in its environmental context.     

The impact of functional analysis methodology on treatment choice for self-injurious and aggressive behavior.

Self-injurious behavior (SIB) and aggression have been the concern of researchers because of the serious impact these behaviors have on individuals' lives. Despite the plethora of research on the treatment of SIB and aggressive behavior, the reported findings have been inconsistent regarding the effectiveness of reinforcement-based versus punishment-based procedures. We conducted a literature review to determine whether a trend could be detected in researchers' selection of reinforcement-based procedures versus punishment-based procedures, particularly since the introduction of functional analysis to behavioral assessment. The data are consistent with predictions made in the past regarding the potential impact of functional analysis methodology. Specifically, the findings indicate that, once maintaining variables for problem behavior are identified, experimenters tend to choose reinforcement-based procedures rather than punishment-based procedures as treatment for both SIB and aggressive behavior. Results indicated an increased interest in studies on the treatment of SIB and aggressive behavior, particularly since 1988.     

A COMPARISON OF NONCONTINGENT REINFORCEMENT AND SENSORY EXTINCTION AS TREATMENTS FOR SELF-INJURIOUS BEHAVIOR

We compared the effects of two treatments, noncontingent reinforcement (NCR) and sensory extinction (EXT), on the self-injurious behavior (SIB) exhibited by 3 individuals with developmental disabilities. Results of a functional analysis indicated that their SIB was not maintained by social reinforcement, as indicated by undifferentiated responding across assessment conditions or higher rates of responding in the alone condition. Prior to treatment, leisure probes were conducted to identify highly preferred items for use in the NCR condition, and equipment probes were conducted to identify devices that produced the greatest behavioral suppression for use in the EXT condition. Following baseline, treatment was implemented in a multiple baseline across subjects design, and the effects of NCR and EXT were compared in a multielement format. During NCR sessions, participants had continuous access to a highly preferred item. During EXT sessions, participants wore equipment (gloves or protective sleeves) that seemed to attenuate stimulation directly produced by their SIB, while still allowing the behavior to occur. Results indicated that both procedures were effective in reducing SIB, although NCR was associated with either more rapid or greater overall response suppression.     

THE ROLE OF ATTENTION IN THE TREATMENT OF ATTENTION-MAINTAINED SELF-INJURIOUS BEHAVIOR: NONCONTINGENT REINFORCEMENT AND DIFFERENTIAL REINFORCEMENT OF OTHER BEHAVIOR

Because there are potentially serious limitations to differential reinforcement of other behavior (DRO) (which is probably the most widely used treatment procedure for behavior problems), we examined an alternative procedure—noncontingent reinforcement (NCR). Three females with developmental disabilities, all of whom engaged in severe self-injurious behavior, participated. During a pretreatment functional analysis, each subject's self-injury was shown to be differentially sensitive to social attention as a maintaining consequence. Next, each subject was exposed to a DRO treatment and an NCR treatment. During DRO, attention was delivered contingent on the absence of self-injury for prespecified intervals. During NCR, attention was delivered on a fixed-time schedule that was not influenced by the subject's behavior. Results showed that both procedures were highly effective in reducing self-injury, probably because the functional reinforcer for self-injury was used during treatment. Furthermore, there was evidence that NCR attenuated several of the limitations of DRO. These results are particularly interesting in light of the long experimental history of NCR as a control rather than as a therapeutic procedure.     

DRO contingencies: an analysis of variable-momentary schedules.

We conducted several comparative analyses to determine the relative effectiveness of variable-momentary differential-reinforcement-of-other-behavior (VM DRO) schedules. Three individuals who had been diagnosed with mental retardation participated. Results of functional analyses indicated that their self-injurious behavior (SIB) was maintained by social-positive reinforcement. Two individuals participated in a two-stage comparative analysis within multielement and multiple baseline designs. Fixed-interval (FI) and variable-interval (VI) DRO were compared in the first stage; VI DRO and VM DRO were compared in the second. All three schedules effectively reduced the participants' SIB. Treatment for the 3rd individual was conducted in a reversal design to examine the effects of VM DRO when it was implemented in isolation, and results indicated that the procedure was effective in reducing SIB. These findings suggest that VM DRO schedules may represent attractive alternatives to traditional FI schedules because momentary schedules do not require continuous monitoring and may result in higher rates of reinforcement.     

ANALYSIS OF THE REINFORCEMENT AND EXTINCTION COMPONENTS IN DRO CONTINGENCIES WITH SELF-INJURY

Previous research has shown that self-injurious behavior (SIB) maintained by positive reinforcement may be reduced under differential-reinforcement-of-other-behavior (DRO) contingencies. In this study, we conducted an analysis of the reinforcement and extinction components of DRO while treating the self-injury of 3 women with developmental disabilities. A functional analysis revealed that each subject's SIB was maintained by positive reinforcement in the form of attention. Subsequent reinforcer assessments identified preferred and nonpreferred stimuli for later use in conjunction with DRO. Results showed high rates of SIB for all 3 subjects during baseline, which persisted when DRO was implemented without the relevant extinction component (withholding of attention for SIB) for 2 of the subjects. Low rates of SIB were observed for all subjects when DRO plus extinction was implemented or when extinction was implemented alone, suggesting that extinction may be a critical component of DRO schedules.     

PROTECTIVE EQUIPMENT AS TREATMENT FOR STEREOTYPIC HAND MOUTHING: SENSORY EXTINCTION OR PUNISHMENT EFFECTS?

We examined the effects of noncontingent and contingent protective equipment as treatment for self-injurious hand mouthing exhibited by 2 individuals with profound mental retardation. Results of a functional analysis assessment revealed that neither subject's self-injury was maintained by social reinforcement: One subject's self-injury was cyclical in nature; the other's occurred during all assessment conditions but most frequently when left alone. In the noncontingent-equipment condition, oven mitts were placed on the individual's hands at the beginning of a session and remained on throughout. In the contingent-equipment condition, the mitts were briefly placed on the individual's hands following occurrences of hand mouthing. For 1 subject, noncontingent mitts produced a large decrease in the rate of hand mouthing and contingent mitts produced similar results following a return to baseline. Hand mouthing was also reduced in the 2nd subject, but this individual was exposed only to the contingent-equipment condition (i.e., there was no prior history with the noncontingent-equipment condition). These results suggest either a punishment or a time-out interpretation rather than an extinction interpretation to account for the behavior-reducing effects of contingent protective equipment on self-injury.     

Functional analysis of self-injurious behavior and its relation to self-restraint

Some individuals who engage in self-injurious behavior (SIB) also exhibit self-restraint. In the present study, a series of three functional analyses were conducted to determine the variables that maintained a participant's SIB, one without restraint items available, one with a preferred and effective form of self-restraint (an airplane pillow) available noncontingently, and one with this item delivered contingent on SIB. Results suggested that SIB was reinforced by escape and by access to self-restraint materials, self-restraint appeared to be maintained by automatic reinforcement, and continuous access to highly preferred restraint materials effectively suppressed SIB.     

Further evaluation of the role of protective equipment in the functional analysis of self-injurious behavior

Using a procedure similar to the one described by Le and Smith (in press), we evaluated the effects of protective equipment during a functional analysis for 2 individuals who engaged in severe self-injurious behavior (SIB). Results of our analyses revealed that the use of protective equipment during functional analyses of SIB suppressed levels of responding such that a behavioral function could not be identified.     

AN ANALYSIS OF THE REINFORCING PROPERTIES OF HAND MOUTHING

Hand mouthing often has been described as a stereotypic response that is maintained by non-social (automatic) reinforcement; however, data supporting this conclusion can be found in relatively few studies. This series of studies presents an experimental analysis of conditions associated with the maintenance of hand mouthing. In Experiment 1, a functional analysis was conducted for 12 individuals who engaged in chronic hand mouthing to determine whether the behavior is usually maintained independent of social contingencies. Results obtained for 10 subjects were consistent with an automatic reinforcement hypothesis; the remaining 2 subjects' hand mouthing was maintained by social-positive reinforcement. Based on these results, Experiment 2 was designed to identify the specific reinforcing properties of hand mouthing. Each of 4 subjects was provided with a toy that substituted for hand mouthing, and preference for a specific topography of toy manipulation (hand-toy contact or mouth-toy contact) was measured. Results indicated that hand stimulation was the predominant reinforcer for all subjects. Experiment 3 provided an extension of Experiment 2 in that the same responses were measured across a variety of toys presented to each of 5 subjects. Results again indicated that hand stimulation was the predominant reinforcer for all subjects. Implications of these results are discussed with relevance to treatment.     

NONCONTINGENT ESCAPE AS TREATMENT FOR SELF-INJURIOUS BEHAVIOR MAINTAINED BY NEGATIVE REINFORCEMENT

We extended research on the role of noncontingent positive reinforcement following a functional analysis of attention-maintained self-injurious behavior to self-injury maintained by negative reinforcement in 2 young males with developmental disabilities. During a pretreatment functional analysis, each participant's self-injury was shown to be differentially sensitive to escape from instructional activities as negative reinforcement. During noncontingent escape, escape from learning activities was provided on a fixed-time schedule that was not influenced by the participant's behavior. One participant was also exposed to differential negative reinforcement of other behavior. During this condition, escape from instructional activities was provided contingent on the omission of self-injury for prespecified intervals. Results showed that the provision of escape, even when noncontingent, resulted in significant reductions in self-injury. These results are particularly interesting in light of the experimental history of noncontingent reinforcement as a control rather than as a therapeutic procedure. Noncontingent escape is discussed as a form of extinction that may be less likely than other forms of extinction to produce severe side effects.     

EFFECTS AND SIDE EFFECTS OF DRO AS TREATMENT FOR SELF-INJURIOUS BEHAVIOR

A three-part controlled case study is presented in which severe and longstanding self-injurious behavior exhibited by a 9-year-old-boy was treated successfully with differential reinforcement of other behavior. In Phase 1, an experimental analysis demonstrated that the boy's scratching was not maintained by environmental contingencies; instead, it appeared that the self-injurious behavior was a stereotypic (automatically reinforced) response. In Phase 2, the effects of an escalating differential-reinforcement-of-other-behavior schedule mediated through token reinforcement (pennies) were evaluated in a reversal design. Results showed that differential-reinforcement-of-other-behavior eliminated self-injurious behavior very quickly and for periods of time as long as 30 min. A noteworthy side effect observed during Phase 2 was the occurrence of crying behavior following the nondelivery of reinforcement. In Phase 3, the token program was gradually extended in 30-min increments throughout the day. Additionally, results of a brief multielement manipulation showed that the effects of token reinforcement were superior to those of a more easily administered differential reinforcement of other behavior based on social reinforcement, which differed little from baseline.     

Correspondence between outcomes of brief and extended functional analyses.

We compared results obtained from 50 sets of functional analysis data from assessments of self-injurious behavior (SIB), 35 of which showed clear response patterns and 15 of which were undifferentiated, with those obtained from two abbreviated methods of assessment: (a) a brief functional analysis, consisting of the first session of each condition from the full functional analysis, and (b) a within-session analysis, in which data from the brief analysis were regraphed to show minute-by-minute changes in response rates during a session. Results indicated that outcomes of the brief and within-session analyses corresponded with those of the full functional analyses in 66.0% and 68.0% of the cases, respectively. Further examination of results indicated a tendency for the brief analysis to identify a large proportion of positive cases (both true and false positives) and for the within-session analysis to identify a large proportion of negative cases (true and false negatives).     

Systematic application and removal of protective equipment in the assessment of multiple topographies of self-injury

We evaluated the effects of systematic application and removal of protective equipment on three topographies of self-injurious behavior (SIB) exhibited by a girl who had been diagnosed with autism. Results showed that when protective equipment was applied, SIB decreased to near-zero levels. In addition, withdrawal of protective equipment for specific topographies of SIB (by removing only the corresponding padding) increased rates of SIB only for that topography of SIB. Next, a functional analysis of hand SIB showed that protective equipment suppressed this behavior in all conditions and that the behavior was maintained by automatic reinforcement when padding was removed. Results are discussed in terms of sensory extinction as a possible mechanism responsible for response suppression.     

Individual and combined effects of noncontingent reinforcement and response blocking on automatically reinforced problem behavior

Noncontingent reinforcement (NCR) and response blocking are 2 common interventions for problem behavior maintained by automatic reinforcement. We implemented NCR and blocking with 1 boy and found this combined intervention to be effective at decreasing high rates of automatically reinforced pica. With another child, we compared the effects of blocking alone to the combined intervention. With the third child, we compared NCR alone and blocking alone to the combined intervention. Results showed that the combined intervention was effective at reducing automatically reinforced problem behavior while moderate to high levels of item engagement maintained. When evaluated individually, neither NCR nor blocking was sufficient to reduce problem behavior to clinically significant levels.     

Rapid assessment of the effects of restraint on self-injury and adaptive behavior

We evaluated the effects of restraint on occurrences of self-injurious behavior (SIB) and adaptive responses exhibited by 2 individuals across eight response-effort conditions: baseline (no restraints); restraint sleeves without stays; restraints with 5, 10, 15, 20, or 25 thin metal stays; and restraints with five thick metal stays. From this analysis, we identified a restraint level for each participant that reduced SIB but did not inhibit adaptive responding.     

Side effects of extinction: prevalence of bursting and aggression during the treatment of self-injurious behavior

Findings from basic and applied research suggest that treatment with operant extinction may produce adverse side effects; two of these commonly noted are an increase in the frequency of the target response (extinction burst) and an increase in aggression (extinction-induced aggression). Although extinction is often used to treat problem behavior in clinical settings, few applied studies have examined the prevalence of these side effects or their possible attenuation with other operant procedures. An analysis of 41 data sets for individuals who received treatment for self-injurious behavior indicated that extinction bursts or increases in aggression occurred in nearly one half of the cases. The prevalence of bursting and aggression was substantially lower when extinction was implemented as part of a treatment package rather than as the sole intervention.     

The effects of response cost in the treatment of aberrant behavior maintained by negative reinforcement

Positive reinforcement contingencies can sometimes be used to decrease problem behavior maintained by negative reinforcement (e.g., escape). In the current study, we evaluated the extent to which response cost (i.e., contingent removal of a preferred stimulus) would compete with the negative reinforcer maintaining destructive behavior. The response cost contingency reduced destructive behavior by 87% from baseline levels even though the negative reinforcement contingency (i.e., escape) remained in place.     

Effects of increased response effort on self-injury and object manipulation as competing responses

We evaluated the effects of a response-effort intervention on the occurrence of self-injurious hand mouthing and a competing response (object manipulation) with 4 individuals who had profound developmental disabilities. During Phase 1, results of functional analyses showed that all participants engaged in high levels of hand mouthing in the absence of social contingencies, suggesting that the behavior was maintained by automatic reinforcement. In Phase 2, preferred leisure items were identified for participants during assessments in which duration of leisure item manipulation was used as the index of preference. In Phase 3, participants were observed to engage in high levels of hand mouthing and in varying levels of object manipulation when they had free access to their most preferred leisure items during baseline. The effects of increased response effort on hand mouthing and object manipulation were then evaluated in mixed multiple baseline and reversal designs. The response-effort condition was identical to baseline, except that participants wore soft, flexible sleeves that increased resistance for elbow flexion but still enabled participants to engage in hand mouthing. Results showed consistent decreases in SIB and increases in object manipulation during the response-effort condition for all participants. These results suggested that a less preferred reinforcer (produced by object manipulation) may substitute for a more highly preferred reinforcer (produced by hand mouthing) when response effort for hand mouthing was increased. DESCRIPTORS: self-injurious behavior, automatic reinforcement, reinforcer substitutability, response effort