A multiple-schedule evaluation of immediate and subsequent effects of fixed-time food presentation on automatically maintained mouthing

The purpose of this study was to evaluate the immediate and subsequent effects of fixed-time (FT) food presentations on mouthing. The effects of FT food presentations were analyzed within a three-component multiple schedule in which baseline conditions were implemented during the first and third components and treatment conditions were implemented during the second component. Results indicated that FT food reduced mouthing and that levels of mouthing during post-FT components were reliably lower than pre-FT components. Behavioral mechanisms responsible for treatment effects are discussed.     

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.     

UTILIZING INCREASED RESPONSE EFFORT TO REDUCE CHRONIC HAND MOUTHING

The effects of increased response effort on levels of hand mouthing, leisure engagement, and adaptive elbow flexion were investigated with 2 individuals who had been diagnosed with profound disabilities. Arm restraints designed to alter the amount of physical effort necessary to engage in hand mouthing were used. Results indicated that the treatment strategy reduced levels of hand mouthing but produced only small to moderate reductions in levels of leisure engagement and adaptive elbow flexion. At follow-up, the effects of increased response effort on hand mouthing and leisure engagement were maintained for both participants; however, the restraints were associated with substantial reductions in adaptive elbow flexion for 1 participant.     

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     

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.     

Immediate and subsequent effects of differential reinforcement of other behavior and noncontingent matched stimulation on stereotypy

A three‐component multiple‐schedule and brief reversals were used to examine the effects of differential reinforcement of other behavior (DRO) and noncontingent matched stimulation (NMS) on the automatically reinforced mouthing of a child with autism. Both DRO and NMS decreased immediate engagement in mouthing, but NMS produced larger reductions in the behavior. Furthermore, NMS produced subsequent effects (i.e., when the treatment was withdrawn) similar to those of prior access, whereas DRO marginally increased subsequent engagement in mouthing. The results suggest that NMS was a functionally matched intervention for mouthing. Implications for the assessment and treatment of stereotypy and applications for future research are discussed. Copyright © 2010 John Wiley & Sons, Ltd.     

The influence of concurrent load on mouthed and vocalized modality effects

A visual search task was coupled with the serial recall of words to assess the extent to which modality effects mediated by vocalizing and silent mouthing reflect an automatically activated preattentive process. Overall, serial position functions systematically changed as concurrent task demands increased, but the magnitude of the modality effect associated with both mouthing and vocalizing was not altered, regardless of whether or not subjects simultaneously searched for digits. These results support the notion that modality effects index a preattentive process that can be activated automatically by either spoken input or gestural cues associated with speech.     

Effects of a verbal warning and overcorrection on stereotyped and appropriate behaviors

In Experiment I, the effects of a verbal warning, such as is used in Overcorrection, delivered contingently on the stereotyped mouthing behavior of two autistic/retarded children were examined. A multiple baseline design across subjects was used. The results indicated that the mouthing of one child was reduced to a nearzero level and mouthing of the second child was moderately reduced. Appropriate toy play and inappropriate object manipulation failed to show systematic changes in occurrence when mouthing was decelerated. In Experiment II, the same subjects and experimental design were used to assess the effects of a positive practice Overcorrection procedure delivered contingent on mouthing behavior. Overcorrection reduced the mouthing of both subjects. There were no systematic changes in inappropriate object manipulation but one subject did demonstrate an increased occurrence of appropriate toy play. In addition, this subject often engaged in aggressive/escape behaviors during Overcorrection, suggesting that the procedure was aversive to him.     

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.     

Assessment and treatment of object mouthing in a public school classroom

Little research has been conducted to evaluate the most effective treatments for object mouthing in school or classroom settings. The current case example illustrates the process for conducting a functional assessment and implementing treatment for object mouthing in a public school special education classroom. Teacher and parent interview, direct observations, and functional analysis were used to determine that the object mouthing of a 4‐year‐old girl with severe developmental disabilities was maintained by automatic reinforcement. Free operant preference assessments determined physical parameters of objects that were highly mouthed. Paired choice preference assessments determined which competing items to use in a treatment evaluation. Initial treatment consisted of fixed‐time delivery of a competing food item that reduced object mouthing to very low levels. To completely eliminate the mouthing, physical response blocking was added. Data are presented demonstrating the success of the treatment for up to 15 weeks of follow‐up after the initial treatment evaluation. Copyright © 2006 John Wiley & Sons, Ltd.     

An evaluation of the effects of matched stimuli on behaviors maintained by automatic reinforcement

The purpose of the current investigation was to extend the literature on matched stimuli to three dissimilar forms of aberrant behavior (dangerous climbing and jumping, saliva manipulation, and hand mouthing). The results of functional analyses suggested that each behavior was automatically reinforced. Preference assessments were used to identify two classes of stimuli: items that matched the hypothesized sensory consequences of aberrant behavior (matched stimuli) and items that produced sensory consequences that were not similar to those produced by the aberrant behavior (unmatched stimuli). The effects of providing continuous and noncontingent access to either the most highly preferred matched or the most highly preferred unmatched stimuli were assessed relative to a condition in which no stimuli were available. Overall results suggested that providing access to items that matched the hypothesized sensory consequences of aberrant behavior may be more effective than simply selecting stimuli either arbitrarily or based on the results of preference assessments alone.     

Recency effects in delayed recall of mouthed stimuli

Auditory presentation leads to greater recency effects in recall than does visual presentation. This phenomenon (the modality effect) is found in both free and serial recall and in both immediate and delayed recall. Silent mouthing of visually presented stimuli also leads to enhanced recency effects in immediate serial recall. Two experiments reported here extend the generality of the mouthing effect by demonstrating that enhanced recency effects of mouthed stimuli occur in delayed serial and free recall. These results are inconsistent with theories that attribute the modality effect to a purely auditory sensory memory.     

Effects of providing sensory stimulation to decrease self-stimulatory behavior: using additional food to suppress hand-mouthing behavior

This study describes the use of sensory stimulation to reduce self-stimulatory behavior of hand mouthing by an institutionalized adult male with profound developmental disabilities. The data showed that when an extra amount of food was presented to eat at meal time, the mouthing behavior decreased quickly to an appreciably lower level. Results suggested that additional food could effectively reduce hand-mouthing behavior in a short period of time if it served a similar function—to provide preferred sensory reinforcers to the individual. An interesting phenomenon which had been observed in this study was a shift in sensory stimulatory behavior or sensory reinforcer from one form to another. While hand mouthing was decreasing, vocalization seemed to be increasing. The advantages of providing additional food as a treatment strategy are discussed with reference to other studies using response inhibition to treat hand mouthing behavior. © 1997 John Wiley & Sons, Ltd.     

Case study: Noninvasive behavioral treatment of self-injurious hand stereotypy in a child with Rett syndrome

Treatment of stereotypic hand mouthing in a 3-year-old girl with Rett syndrome by differential reinforcement of competing functional responses plus response interruption is described and evaluated in this case study. A package of graduated guidance with social and edible reinforcers successfully established stable rates of functional hand movements to activate toys, gross motor responses to verbal prompts, palmar grasp and release, and some vocal imitation. Contingent response interruption virtually eliminated hand mouthing during instructional sessions. Instruction alone did not maintain hand mouthing suppression when interruption was withdrawn, and treatment gains appeared highly discriminated. Post-hoc comparison indicated differential reinforcement plus response interruption (DR1 + 1) to be superior to hand splints in reducing hand stereotypies, with approximately equivalent increases in collateral tongue thrusting.     

Successful generalized parent training and failed schedule thinning of response blocking for automatically maintained object mouthing

Mouthing of inedible objects maintained by automatic reinforcement can be particularly difficult to treat, given that the functional reinforcer is not socially mediated, and therefore it is difficult or impossible to withhold reinforcement. In the current investigation, response blocking was used to reduce automatically maintained object mouthing. Treatment effects were generalized to the natural environment. An attempt at schedule thinning was not successful; however, the participant's parents were trained to implement the treatment successfully in their home. Copyright © 2002 John Wiley & Sons, Ltd.     

A METHODOLOGY FOR DISTINGUISHING BETWEEN EXTINCTION AND PUNISHMENT EFFECTS ASSOCIATED WITH RESPONSE BLOCKING

We present one method for distinguishing between extinction and punishment effects. The proportion of responses that produced a consequence (blocking) was varied while hand mouthing was treated in a man diagnosed with profound mental retardation. Response patterns across the schedule changes suggested that the blocking procedure functioned as a punishing event.     

Increasing item engagement and decreasing automatically reinforced problem behavior within a modified competing stimulus assessment

A competing stimulus assessment (CSA) is commonly used to identify leisure items for use in treatments designed to decrease automatically reinforced problem behavior. However, this type of assessment may not yield useful information if participants do not readily engage with leisure items. The purpose of this study was to evaluate a modified CSA that included additional treatment components (i.e., prompting, prompting plus differential reinforcement of alternative behavior). The modified CSA identified the treatment components and leisure items that were most effective for increasing leisure-item engagement and decreasing problem behavior for each participant. Modified CSA outcomes maintained during an extended treatment analysis in a natural setting and when intervention components were faded.     

REDUCTION OF SELF-INJURIOUS HAND MOUTHING USING RESPONSE BLOCKING

We evaluated a response-blocking procedure for reducing the self-injurious hand mouthing of 2 adults with profound disabilities. The procedure reduced mouthing in both cases. The results suggest research is warranted to delineate the behavioral process responsible for the effect of response blocking and to determine the procedure's long-term utility.     

On the relative contributions of positive reinforcement and escape extinction in the treatment of food refusal

We compared the effects of positive reinforcement alone, escape extinction alone, and positive reinforcement with escape extinction in the treatment of the food and fluid refusal of 4 children who had been diagnosed with a pediatric feeding disorder. Consumption did not increase when positive reinforcement was implemented alone. By contrast, consumption increased for all participants when escape extinction was implemented, independent of the presence or absence of positive reinforcement. However, the addition of positive reinforcement to escape extinction was associated with beneficial effects (e.g., greater decreases in negative vocalizations and inappropriate behavior) for some participants.     

DISTINGUISHING BETWEEN EXTINCTION AND PUNISHMENT EFFECTS OF RESPONSE BLOCKING: A REPLICATION

Lerman and Iwata (1996) described a method for distinguishing between sensory extinction and punishment effects of response blocking on self-injurious behavior maintained independent of social contingencies. Results of their study suggested that blocking decreased the self-injurious hand mouthing of their participant via punishment. The current replication of these procedures with the self-injurious eye poking of a woman with developmental disabilities produced patterns of responding indicating that, for this participant, blocking functioned as an extinction procedure.