The functions of self-injurious behavior: an experimental-epidemiological analysis

Comparison of reinforcement schedules in the reduction of stereotypy with supported routines

The rates and durations of stereotypic behaviors in four adolescents with severe mental retardation were measured during two daily vocational training sessions and during contiguous periods of leisure in their special education classrooms. Vocational training was conducted in two different tasks, alternating across days. The task requirements for each participant were matched to each participant's learning and performance characteristics. The participants were exposed to a fixed ratio schedule of tokens exchangeable for food items on one task and to a variable interval schedule for the same consequences on the second task. The schedules were chosen as an initial test of a matching-law based prediction by Myerson and Hale (1984): Variable interval reinforcement for adaptive behavior will produce less allocation of responding to maladaptive behavior than will a ratio-based intervention. When work performances stabilized, the schedules of token delivery were reversed across the tasks and performances again stabilized. Results are reported for periods when work performances met stability criteria. Stereotypy occurred more during leisure than during vocational training under either schedule. The major differences in stereotypy between leisure and vocational training were differences in episode length rather than rate of onset. Onset of stereotypy in vocational training, however, occurred at higher rates under the interval schedule than under the ratio schedule in both tasks. The results are discussed in terms of Myerson and Hale's prediction and implications for further research and application.

The evaluation and treatment of aggression maintained by attention and automatic reinforcement

In the current investigation, we used direct and indirect methods to assess and treat several topographies of aggression that were hypothesized to have separate operant functions in a young boy with severe mental ratardation and pervasive developmental disorder. First, a functional analysis of aggression, using the methods described by Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994), was conducted and produced inconclusive results. Next, indirect methods were used to develop a second functional analysis, which showed that chin grinding (firmly pressing and grinding his chin against the skin and bones of others) persisted independent of social contingencies and that the other topographies of aggression (e.g., hitting, kicking) were maintained by social positive reinforcement (attention). A treatment designed to decrease aggression maintained by attention--functional communication training with extinction--reduced all forms of aggression except chin grinding. This latter topography of aggression, which we hypothesized was maintained by automatic reinforcement, was reduced when the response--reinforcer relation was interrupted through response blocking and the child was provided with an alternative form of chin stimulation.

Functional analysis and treatment of destructive behavior maintained by termination of "don't" (and symmetrical "do") requests

We used descriptive assessment information to generate hypotheses regarding the function of destructive behavior for 2 individuals who displayed near-zero rates of problem behavior during an experimental functional analysis using methods similar to Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994). The descriptive data suggested that destructive behavior occurred primarily when caregivers issued requests to the participants that interfered with ongoing high-probability (and presumably highly preferred) behaviors (i.e., a "don't" or a symmetrical "do" request). Subsequent experimental analyses showed that destructive behavior was maintained by contingent termination of "don't" and symmetrical "do" requests but not by termination of topographically similar "do" requests. These results suggested that destructive behavior may have been maintained by positive reinforcement (i.e., termination of the "don't" request allowed the individual to return to a highly preferred activity). Finally, a treatment (functional communication training plus extinction) developed on the basis of these analyses reduced destructive behavior to near-zero levels.

Treatment of pica through multiple analyses of its reinforcing functions

We conducted functional analyses of the pica of 3 participants. The pica of 1 participant appeared to be maintained by automatic reinforcement; that of the other 2 participants appeared to be multiply controlled by social and automatic reinforcement. Subsequent preference and treatment analyses were used to identify stimuli that would complete with the automatic function of pica for the 3 participants. These analyses also identified the specific aspect of oral stimulation that served as automatic reinforcement for 2 of the participants. In addition, functional analysis-based treatments were used to address the socially motivated components of 2 of the participants' pica. Results are discussed in terms of (a) the importance of using the results of functional analyses to develop treatments for pica and (b) the advantages of developing indirect analyses to identify specific sources of reinforcement for automatically reinforced behavior.

Establishing discriminative control of responding using functional and alternative reinforcers during functional communication training

Functional communication training (FCT) is a popular treatment for problem behaviors, but its effectiveness may be compromised when the client emits the target communication response and reinforcement is either delayed or denied. In the current investigation, we trained 2 individuals to emit different communication responses to request (a) the reinforcer for destructive behavior in a given situation (e.g., contingent attention in the attention condition of a functional analysis) and (b) an alternative reinforcer (e.g., toys in the attention condition of a functional analysis). Next, we taught the participants to request each reinforcer in the presence of a different discriminative stimulus (SD). Then, we evaluated the effects of differential reinforcement of communication (DRC) using the functional and alternative reinforcers and correlated SDs, with and without extinction of destructive behavior. During all applications, DRC (in combination with SDs that signaled available reinforcers) rapidly reduced destructive behavior to low levels regardless of whether the functional reinforcer or an alternative reinforcer was available or whether reinforcement for destructive behavior was discontinued (i.e., extinction).

Effectiveness of functional communication training with and without extinction and punishment: a summary of 21 inpatient cases

Functional communication training (FCT) is a frequently used treatment for reducing problem behavior exhibited by individuals with developmental disabilities. Once the operant function of problem behavior is identified by a functional analysis, the client is taught to emit an appropriate communicative response to obtain the reinforcer that is responsible for behavioral maintenance. Studies on FCT have typically used small numbers of participants, have reported primarily on clients for whom FCT was successful, and have varied with respect to their use of other treatment components. The main purposes of the present study were to evaluate the efficacy of FCT for treating severe problem behavior in a relatively large sample of individuals with mental retardation (N = 21) and to determine the contribution of extinction and punishment components to FCT treatment packages. FCT with extinction was effective in reducing problem behavior for the majority of clients and resulted in at least a 90% reduction in problem behavior in nearly half the applications. However, when demand or delay-to-reinforcement fading was added to FCT with extinction, treatment efficacy was reduced in about one half of the applications. FCT with punishment (both with and without fading) resulted in at least a 90% reduction in problem behavior for every case in which it was applied.

Self-injurious behaviour and body site preference

Self-injury by people with intellectual disabilities is a highly problematic and damaging behaviour with profound implications for quality of life. To date, very little detailed descriptive information has been available on the distribution and location of body sites that are injured. This study presents preliminary information on the locations of the self-injury body sites of 29 school-age individuals with developmental and intellectual disabilities who self-injured daily. Teaching staff in school-based special education programmes independently recorded the body locations of where their student's self-injured. Approximately 80% of the reported self-injury was directed disproportionately toward the head and hands. Three-quarters of head-directed self-injury was located on the front of the head, and 83% of hand-directed self-injury was located on the back of the hands. Furthermore, 32% of the body sites toward which self-injury was directed were located on stimulation-produced analgesia body sites. The implications of these findings are discussed in relation to the opioid hypothesis of self-injurious behaviour, and with regard to future research investigating functional diagnostic strategies considering both social and biological variables.

Stimulus control and resistance to extinction in attention-maintained SIB

A functional analysis of the self-injurious behavior (SIB) of a young man diagnosed with severe mental retardation demonstrated that SIB was sensitive to social attention as reinforcement. In addition, lower but consistent rates of SIB occurred in sessions where a person was present (Demand and Toy Play), and a gradual decrease in SIB was observed across sessions where a person was not present (Alone). Evaluation of the within-session trends of SIB during the functional analysis demonstrated that SIB maintained throughout each Social Attention session and declined within and across Alone sessions. This pattern of responding suggested that the presence of a person may have differentially affected rates of SIB independent of the programmed consequences for SIB. In a subsequent analysis, SIB was reduced to near-zero levels in the absence of a person, but maintained in the presence of a person even when attention was withheld, suggesting that the response was highly resistant to extinction. The results of these assessments then were used to develop a treatment to reduce the client's SIB. During treatment, a person was present and delivered attention only when the client appropriately communicated. SIB resulted in the removal of the antecedent stimulus that exerted control over the response (i.e., the person left the room). The findings of this investigation are discussed in terms of the differential effects of stimuli on interpretation of functional analysis results and the subsequent development of treatment.

Issues on functional analysis in behavioral assessment

The rebirth of interest in functional analysis is described. Clarification among conflicting terms is offered as a way of facilitating research in the area. Three phases of functional approach to assessment are identified: (a) descriptive, (b) interpretive, and (c) verification. Five assessment methods common to assessment, generally, are shown to be useful in both descriptive and verification phases. Evaluation of functional approaches requires attention to the psychometric adequacy of these methods. Accuracy, reliability, and validity concepts are reviewed briefly and their application to functional strategies is described. The use of treatment validity in the functional analysis of functional analysis is mentioned as the ultimate strategy for evaluating the adequacy of this assessment approach. The paper ends with a discussion of problems of multiple control of behavior, behavioral classification systems, training parents and other mediators in the functional approach, cost-effectiveness, and the place of functional analysis in a reorganized health care delivery system.

The effect of noncontingent sensory reinforcement, contingent sensory reinforcement, and response interruption on stereotypical and self-injurious behavior

Three analyses were conducted to assess the effects of different consequent stimuli on the rate of stereotypical and self-injurious behavior performed by two individuals with severe developmental disabilities and dual sensory impairments. An analogue functional analysis documented an undifferentiated pattern of problem behavior across all conditions for Participant 1. Data for Participant 2 indicated an undifferentiated pattern with lower frequencies in the demand condition. Stimuli chosen to compete with the type of sensory stimulation produced by the stereotypy and self-injurious behavior were presented noncontingently during play conditions. Noncontingent presentation of the specially selected stimuli resulted in reductions in stereotypy and self-injurious behavior. Finally, contingent presentation of the same stimuli with and without response interruption was assessed in a demand context. Contingent presentation of the specially selected stimuli plus response interruption resulted in more suppression than contingent sensory stimulus presentation alone. Results are discussed as to competing and concurrent schedules of reinforcement.

Noncontingent presentation of attention and alternative stimuli in the treatment of attention-maintained destructive behavior

Previous research has demonstrated that destructive behavior may be reduced through noncontingent presentation of attention when attention is identified as the stimulus responsible for behavioral maintenance. Because it may not always be possible to deliver attention in all situations, we examined the extent to which alternative stimuli that have been identified through a choice assessment would substitute for attention (the functional analysis-based reinforcer) in a noncontingent reinforcement procedure. Prior to treatment, functional analyses demonstrated that the destructive behavior of 2 clients with mental retardation was maintained by adult attention. Next, a stimulus choice assessment identified highly preferred tangible items for the 2 clients. Finally, we compared the effectiveness of two noncontingent reinforcement procedures: continuous noncontingent access to attention and continuous noncontingent access to the tangible item identified in the choice assessment. For both clients, these noncontingent reinforcement procedures reduced destructive behavior. The results are discussed in terms of the clinical implications for the treatment of destructive behavior using functional and alternative stimuli.

On the relation of mands and the function of destructive behavior

When standard analogue functional analysis procedures produce inconclusive results in children with conversational speech, the child's mands may help to identify the function of destructive behavior. In the current investigation, functional analyses conducted with 2 children who exhibited self-injury, aggression, and property destruction were undifferentiated across conditions. Based on informal observations and school and parental report, an analysis was conducted using mands to help determine the function of the destructive behavior. Using a multielement design, the therapist's compliance with the child's mands occurred either on a fixed-ratio (FR) 1 schedule or contingent on destructive behavior. Destructive behavior occurred at high and consistent levels when reinforcement of mands was contingent on destructive behavior and at near-zero levels when reinforcement of mands occurred on the FR 1 schedule. Based on these results, a second analysis was conducted in which compliance to mands occurred only when the child appropriately requested it (i.e., functional communication training plus extinction) and, for 1 child, compliance with mands was terminated contingent upon destructive behavior (i.e., functional communication training plus response cost). For both children, the rates of destructive behavior decreased markedly. The results suggest that assessing the child's mands may be useful in decreasing destructive behavior when a functional analysis is inconclusive.

An analysis of reinforcer substitutability using object manipulation and self-injury as competing responses

The concept of reinforcer substitutability proposes a continuum of interactions among reinforcers in a given situation. At one end of this continuum, reinforcers are substitutable, with one reinforcer being readily traded for another. We conducted an analysis of reinforcers that were substitutable with those produced by self-injurious behavior (SIB). Three individuals with profound developmental disabilities, whose SIB appeared to be maintained by automatic reinforcement, participated. Results of three experiments showed that (a) object manipulation and SIB were inversely related when leisure materials and SIB were concurrently available, with participants showing almost complete preference for object manipulation; (b) attempts to reduce SIB using the preferred objects as reinforcers in differential reinforcement contingencies were unsuccessful for all 3 participants; and (c) participants' preferences for SIB or object manipulation systematically changed when reinforcer cost (the amount of effort required to obtain the object) was varied. Results of the three experiments illustrate the importance of examining interactions among concurrently available reinforcers when conducting reinforcer assessments.

The use of positive and negative reinforcement in the treatment of escape-maintained destructive behavior

We identified 3 clients whose destructive behavior was sensitive to negative reinforcement (break from tasks) and positive reinforcement (access to tangible items, attention, or both). In an instructional context, we then evaluated the effects of reinforcing compliance with one, two, or all of these consequences (a break, tangible items, attention) when destructive behavior produced a break and when it did not (escape extinction). For 2 clients, destructive behavior decreased and compliance increased when compliance produced access to tangible items, even though destructive behavior resulted in a break. For 1 client, extinction was necessary to reduce destructive behavior and to increase compliance. Subsequently, when the schedule of reinforcement for compliance was faded for all clients, destructive behavior was lower and fading proceeded more rapidly when compliance produced multiple functional reinforcers (i.e., a break plus tangible items or attention) and destructive behavior was on extinction. The results are discussed in terms of the effects of relative reinforcement value and extinction on concurrent operants.

A functional-analytic approach to the diagnosis of a transient tic disorder

The diagnostic utility of functional analyses has been demonstrated with a variety of behaviors including tics. Whereas previous analyses have focused on the discovery of maintaining variables to aid in treatment prescription, we employed a functional analysis to confirm a clinical diagnosis. An 11 year old male student, who had not been previously diagnosed with a tic disorder, exhibited multiple vocal tic-like behaviors which had persisted over a period of time. Teacher reports conflicted regarding the possible etiology of these behaviors. Hence, a functional analysis was conducted in the classroom to determine if the behaviors were maintained by operant variables. Our hypothesis stated that the occurrence of vocal behaviors across experimental conditions would strongly indicate the presence of a tic disorder. The functional analysis included the following conditions: attention, escape, alone, freeplay, and high sensory stimulation. We used a multi-element design to evaluate the effects of the different stimulus conditions on vocal-behavior frequency. Data indicated the student exhibited vocal behaviors in all conditions. However, the behaviors were partially exacerbated in the attention and escape conditions. Results supported the diagnosis of a transient tic disorder affected by operant variables.

Time-based lag sequential analysis and the functional assessment of challenging behaviour

This paper describes the application of time-based lag sequential analysis to the functional assessment of challenging behaviours shown by people with severe learning disabilities. The potential uses of the approach are illustrated with regards to identifying: (1) aspects of the stimulus control of challenging behaviour; (2) antecedents to the occurrence of challenging behaviour; and (3) the environmental consequences of challenging behaviour. The uses and limitations of the approach are discussed.

More theory-driven and less diagnosis-based behavior therapy

Individualized treatment based on a functional analysis of problem behavior used to be considered a hallmark of behavior therapy. Yet the relative success of recently developed treatment manuals for DSM-defined disorders has cast doubts as to whether treatment individualization is really necessary. This article evaluates some of the relative merits of assessments and manualized treatments based on DSM categories and discusses data that indicate when a protocol treatment approach is sufficient and when it is not. Finally, a theory-driven approach to conducting behavior therapy is proposed as a way to complement individualized and manualized treatments. This approach is illustrated by presenting a model-based assessment and treatment approach to overcome excessive heart-focused anxiety (cardiophobia).

Some current themes in functional analysis research

The purpose of this article is to review and discuss some current themes in functional analysis research. The paper is divided into two general sections; one section discusses clinical application of functional analysis and a second section discusses functional analysis as a research method. In the first section, current issues related to treatment logic and development are reviewed. Also, clinical limitations of functional analysis are described, including treatment and assessment implementation issues (such as time and resource constraints). In the second section, three areas of research are reviewed with suggestions for further research: the analysis of diverse response topographies, the analysis of basic behavioral processes, and the evaluation of methodological refinements.

The effects of meal schedule and quantity on problematic behavior

We present 2 case examples that illustrate the effects of meal schedule and quantity on displays of problematic behavior. In the first example, self-injury displayed by a toddler with severe developmental delays was maintained by parent attention, but only when he was satiated for food. When he was food deprived, self-injury decreased but did not appear to be differentiated across low or high social conditions. In the second example, crying and self-injury displayed by an elementary-aged girl with severe disabilities were correlated: Both behaviors were associated with food quantity, and neither behavior was responsive to social stimuli. These results replicate and extend previous findings demonstrating that meal schedule or food quantity can affect problematic behavior. In the present studies, brief functional analyses of aberrant behavior provided useful information for interpreting distinct patterns of behavior displayed by each child. We discuss these results in terms of the concept of establishing operations.

Functional analysis and treatment of cigarette pica

A series of analyses was conducted to assess and treat the pica of cigarette butts by a young man with mental retardation and autism. First, we demonstrated that pica was maintained in a condition with no social consequences when the available cigarettes contained nicotine but not when the cigarettes contained herbs without nicotine. Second, a choice assessment (Fisher et al., 1992) confirmed that tobacco was preferred over the other components of the cigarette (e.g., paper, filter, etc.). Third, an analogue functional analysis (Iwata, Dorsey, Slifer, Bauman & Richman, 1982/1994) demonstrated that cigarette pica was maintained independent of social consequences. Fourth, a treatment designed to interrupt the hypothesized response-reinforcer relationship reduced consumption of cigarettes to zero. Finally, because cigarette pica occurred primarily when the individual was alone or under minimal supervision, a procedure based on stimulus control was developed to improve the effectiveness of the intervention in these situations.

Analog baselines: a critical review of the methodology

Analog baselines are an experimental methodology for identifying the functions of maladaptive behavior in the naturally occurring environment (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982; Iwata et al., 1994). This article identifies a number of potential limitations in this methodology. These include: (a) procedural problems inherent in the use of multielement designs, (b) the fidelity of analog baseline design conditions, (c) the relation of the analog conditions to the naturally occurring environment, (d) a narrow analysis of behavior limited by an implicit adherence to an ABC model of behavior, (e) a limited acknowledgement of multifunction and idiosyncratically motivated behaviors, (f) problems in the definition of response classes, and (g) difficulties in the use of analog baselines to design interventions. Future research should attend to three main questions. First, the convergent validity of different assessment methodologies, including analog baselines, should be evaluated. Future research should attend to procedures that can integrate the entire clinical process of referral, identifying the functions of the target behavior, including other methods of identifying the functions of behavior, treatment design, and implementation. Second, assessment failures could be examined carefully to identify ways of developing this methodology further. Third, the process of designing an intervention depends upon input from many sources of information. The use of analog baselines will be enhanced by a greater understanding of the process of clinical decision making.

Descriptive analysis of multiple response topographies of challenging behavior across two settings

Time-based lag sequential analyses were conducted on 23 topographies of challenging behavior shown by five young people with severe mental retardation across two settings. Potential behavioural functions were identified for 21 of the 23 behaviors. Responses classes, including two or more distinct behaviors, were identified for four of the five participants. Two participants showed evidence of two functionally distinct response classes; for one person each response class included both self-injurious and stereotypic behaviors. For 9 of the 11 behaviors for which data were available, the hypothesised function of behaviors was consistent across settings. For one person, data suggested that the function of one self-injurious behavior was contextually determined. Cross-validation with brief experimental analyses resulted in agreement on the general behavioral function for 12 of the 14 instances in which both approaches positively identified a potential function for a behavior. Implications for future research and practice are discussed.

Functional analysis and treatment of eye poking

In four studies we analyzed the eye poking of a youth with profound disabilities. In Study 1, a functional analysis showed that eye poking occurred during the no-attention condition, but not during demand, attention or recreation conditions. The analysis did not identify socially mediated variables involved in the maintenance of eye poking; rather, eye poking may have been maintained by consequences produced directly by the response. In Study 2 we had the student wear goggles to prevent potential reinforcement from finger-eye contact. The results of Study 2 indicated that eye-poking attempts were reduced when the student wore goggles. We then tested in Study 3 the effects of two alternative topographies of stimulation. Study 3 demonstrated that eye poking was reduced when a video game was provided as a competing source of visual stimulation, and that music was less effective in reducing eye poking. In Study 4, a contingency analysis using the video game was conducted in an attempt to (a) reduce the frequency of eye poking and (b) study whether the video game functioned as a reinforcer. The results of Study 4 demonstrated substantive reductions in the frequency of eye poking, and suggested that the video game served as a reinforcer.

An analysis of the reinforcing properties of hand mouthing

Hand mouthing often has been described as a stereotypic response that is maintained by nonsocial (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.

Pyramidal staff training in the extension of treatment for severe behavior disorders

We implemented a pyramidal training procedure for staff working with individuals who exhibited self-injurious behavior (SIB), aggression, and disruption. Two adults with developmental disabilities and their direct-care staff and supervisors participated. Following successful treatment by the experimenters, two types of baselines were conducted with the clients and their direct-care staff. During an initial baseline, the staff implemented preexisting procedures. Staff members then received instruction on the new treatment procedures using training methods common throughout the institution, and data were collected during this "post-in-service" baseline. Experimenters then taught unit supervisors to implement treatment, collect and interpret data, and provide similar instructions and feedback to the staff members. The supervisor training was implemented in a multiple baseline design across subjects (clients and direct-care staff). Results showed little change following in-service training but noticeable improvements in direct-care staff behaviors and corresponding decreases in the clients' inappropriate behavior following the pyramidal training intervention with supervisors. Six additional clients (along with their direct-care staff and supervisors) participated in pre- and posttreatment replication designs, and their results provided additional support for the efficacy of the supervisor training procedures.

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.

Assessing the functions of self-injurious behavior: a case of assessment failure

Seven attempts to assess the function of self-injurious behavior in a person with profound mental retardation are described. Although repeated correlational and experimental methods were implemented to determine the functional role of this behavior no clear functions were identified. A clinical implication of this case and that this methodology is not all-embracing. Different assumptions should be explored after substantial efforts have failed.

Treatment of self-injury and hand mouthing following inconclusive functional analyses

Numerous studies have used functional analyses to prescribe interventions for severe behavior disorders. The majority of these studies have focused on behavior that is clearly maintained by socially mediated reinforcement, such as contingent access to attention, tangibles, or escape from instructional demands. However, a significant proportion of functional analyses do not yield conclusive results. We examined interventions for 3 children with severe disabilities following inconclusive functional analyses. First, preferred stimuli were identified for each child via a stimulus preference assessment. Second, a functional analysis was conducted for 2 of the 3 children. High rates of aberrant behavior were seen even (if not especially) in no-interaction sessions. The 3rd child was observed for several consecutive no-interaction sessions; behavior persisted in this condition. Third, interventions based on environmental enrichment were analyzed in an analogue setting. For all of the children, environmental enrichment decreased aberrant behavior if preferred stimuli were used in the procedure. To obtain further reductions in aberrant behavior, explicit reinforcement of toy play was required for 2 children, and a brief (5-s) time-out was necessary with 1 child. Finally, effects of treatment carried over to the school or home environment following teacher or family training. Results are discussed in the context of basic reinforcement principles and future directions for research.

Multiple functions of problem behaviors: assessment and intervention

Three individuals with severe intellectual disabilities participated in separate analyses of problem behavior. In each case, a functional analysis was conducted under two parallel conditions. In one condition, self-injury or aggression resulted in escape from difficult tasks; in the second condition, the same problem behavior resulted in access to preferred items. Results indicated that the problem behaviors for each participant were maintained by both types of contingencies. Functional communication training was then delivered first in one condition and then in the second. After each participant was trained in a functionally equivalent mode of communication for one condition, levels of problem behavior decreased in that condition but not in the untrained condition. Only after separate communication forms were trained in both conditions was problem behavior reduced to clinically acceptable levels. These results document three examples of problem behaviors under multiple control, and emphasize the need to organize interventions that address different contingencies of reinforcement that maintain the same problem behavior.