THE LIMITS AND MOTIVATING POTENTIAL OF SENSORY STIMULI AS REINFORCERS FOR AUTISTIC CHILDREN

This study investigated the reinforcing properties, limits, and motivating potentials of sensory stimuli with autistic children. In the first phase of the study, four intellectually retarded autistic children were exposed to three different types of sensory stimulation (vibration, music, and strobe light) as well as edible and social reinforcers for ten-second intervals contingent upon six simple bar pressing responses. In the second phase, the same events were used as reinforcers for correct responses in learning object labels. The results indicated that: (a) sensory stimuli can be used effectively as reinforcers to maintain high, durable rates of responding in a simple pressing task; (b) ranked preferences for sensory stimuli revealed a unique configuration of responding for each child; and (c) sensory stimuli have motivating potentials comparable to those of the traditional food and social reinforcers even when training receptive language tasks.     

The generality of overselectivity in developmentally disabled children

A growing body of research suggests that low Mental Age (MA) autistic and retarded children show a unique stimulus control deficit, one that may cause many or most of their behavioral deficiencies. This problem, stimulus overselectivity, is evidenced when a child responds only to a restricted portion of the stimulus environment when compared with normal children. The purpose of this study was to assess whether this overselectivity is general across situations or whether it is restricted to certain stimulus/task conditions. Eight autistic children, who evidenced overselectivity on a preassessment task, and 8 normal children with similar MA levels participated. All children were trained on 3 tasks to determine if overselectivity varied as a function of different stimulus conditions. Each of the 3 tasks involved training a child to respond to (i.e., touch) a card containing a circle (S +) and to avoid a blank (S ?) card. In each case, the circle comprised a series of dots. The difference between the 3 circles (tasks) was the distance between the successive dots making up each circle. Also, in the minimal separation condition the dots were smaller in size and greater in number than in the larger separation conditions. Of concern was whether autistic children learned about the gestalt (i.e., the circle), which required attention to multiple cues, or whether children would overselect and respond to the dots. The results showed that (1) stimulus overselectivity was found not to be a generalized deficit in autistic subjects; instead, it varied as a function of the stimulus variables; and (2) the stimulus variables manipulated in this study similarly influenced the responding of both normal and autistic children. The implications of these data for a theory of overselectivity are discussed.     

Classroom treatment of autistic children: II. individualized instruction in a group

This study was designed to assess the feasibility of providing individualized instruction in a classroom of autistic children. In particular, we investigated whether students' unsupervised responding was a variable which would influence the effectiveness of individualized instruction procedures. Initially, one teacher attempted to teach different academic behavior to four autistic children simultaneously. During these sessions the teacher rotated from child to child, providing individualized instructions and reinforcers to each. We found, however, that each child stopped responding whenever the teacher rotated to a different child and, further, no academic progress occurred for any of the children during these sessions. In a multiple baseline design, treatment procedures were then introduced (prompt fading, chaining, and programmed instructional materials) to teach each student to continue working for an extended period of time after each instruction from the teacher. After treatment, sessions of individualized instruction in a group were reintroduced for each child. The results showed that unsupervised responding was an important variable influencing the effectiveness of individualized instruction. Specifically, the data show that (1) unsupervised responding, acquired during treatment, generalized to the group setting; (2) after treatment, each child began to make progress on his assigned tasks; and (3) programming instructional materials in small steps appeared to be necessary in order to ensure the maintenance of unsupervised responding across changes in instructional materials. By the end of this study it was possible for one teacher to simultaneously teach four autistic children — with each child learning at his own rate, on his own task, with minimal supervision from the teacher. It is suggested that the generalizability of these results, to other settings where continuous supervision is difficult, may be an important concern of future research.     

Selective responding to the components of multiple visual cues by autistic children

Fifteen autistic and 15 normal Ss were trained to respond to a card containing two visual cues. After this training disctimination was established, the children were tested on the single cues in order to assess whether one or both stimuli had acquired control over their responding. The autistic children (12 of 15) gave evidence for stimulus overselectivity in that they responded correctly to only one of the two component cues. On the other hand, the normal children (12 of 15) showed clear evidence of control by both component cues of the training card. These results were consistent with previous studies, where autistics showed overselectivity when presented with multiple sensory input in several modalities. However, now autistic children appear to have difficulty responding to multiple cues even when both cues are in the same modality. These results were discussed in relation to the experimental literature on selective attention in normally functioning organisms.     

Comparing autistic and normal children along the dimensions of reinforcement maximization, stimulus sampling, and responsiveness to extinction

The purpose of this study was to assess autistic children's ability to maximize reinforcement, sample among available stimuli, and respond to extinction. Responding to five concurrent reinforcement schedules (CRF, FR 2, FR 4, FR 7, and FR 11) was monitored and compared to groups of mental age-matched and chronological age-matched normal children. When a given child consistently selected a given schedule of reinforcement, it was then put on extinction, and both perseveration and responding to the remaining (intact) schedules of reinforcement were monitored. The results showed, first, that while normal children selected the richest schedule of reinforcement, autistics did not maximize reinforcement, typically selecting one of the thinner schedules available. Second, the autistic children sampled less, and less efficiently, than the normal children. Third, the autistic children proved to be much less responsive to extinction, perseverating longer than the normal children before switching to a new reinforcement schedule. Fourth, whenever extinction proved to be a problem in the autistics, it was quickly achieved by a simple change in the stimulus conditions. These results are discussed as possible "keystone" deficits, which may be causally related to many of the behavioral deficits of autism and which might be important target behaviors for treatment.     

TOO MUCH REINFORCEMENT,TOO LITTLE BEHAVIOR: ASSESSING TASK INTERSPERSAL PROCEDURES IN CONJUNCTION WITH DIFFERENT REINFORCEMENT SCHEDULES WITH AUTISTIC CHILDREN

Task interspersal procedures have been quite effective in increasing autistic children's motivation to learn. These procedures have typically demonstrated that the inclusion of reinforced maintenance tasks (previously learned tasks) increases responding to new acquisition tasks because more reinforcers, in general, are available. However, studies have not specifically addressed the effects of various schedules of reinforcement, used in conjunction with task interspersal procedures, upon response acquisition. In the present study, a multiple baseline design across subjects was used to assess different reinforcement schedules. Five autistic children participated in learning sessions, during which trials of an acquisition task were interspersed with trials of three maintenance tasks. Correct responses to acquisition tasks were continuously reinforced throughout all conditions, while the reinforcement schedule for competent performance of maintenance tasks differed systematically. Results indicated that all children learned the new tasks when food reinforcers were presented only for acquisition tasks. Results are discussed in terms of behavioral contrast and improving the effectiveness of motivation-enhancing procedures for autistic children.     

SENSORY EXTINCTION AND SENSORY REINFORCEMENT PRINCIPLES FOR PROGRAMMING MULTIPLE ADAPTIVE BEHAVIOR CHANGE

The role of sensory reinforcement was examined in programming multiple treatment gains in self-stimulation and spontaneous play for developmentally disabled children. Two phases were planned. First, we attempted to identify reinforcers maintaining self-stimulation. Sensory Extinction procedures were implemented in which auditory, proprioceptive, or visual sensory consequences of self-stimulatory behavior were systematically removed and reintroduced in a reversal design. When self-stimulation was decreased or eliminated as a result of removing one of these sensory consequences, the functional sensory consequence was designated as a child's preferred sensory reinforcer. In Phase 2, we assessed whether children would play selectively with toys producing the preferred kind of sensory stimulation. The results showed the following. (1) Self-stimulatory behavior was found to be maintained by sensory reinforcement. When the sensory reinforcer was removed, self-stimulation extinguished. (2) The sensory reinforcers identified for self-stimulatory behavior also served as reinforcers for new, appropriate toy play. (3) The multiple treatment gains observed appeared to be relatively durable in the absence of external reinforcers for play or restraints on self-stimulation. These results illustrate one instance in which multiple behavior change may be programmed in a predictable, lawful fashion by using “natural communities of sensory reinforcement.”     

THE FUNCTIONS OF SELF-INJURIOUS BEHAVIOR: AN EXPERIMENTAL-EPIDEMIOLOGICAL ANALYSIS

Data are summarized from 152 single-subject analyses of the reinforcing functions of self-injurious behavior (SIB). Individuals with developmental disabilities referred for assessment and/or treatment over an 11-year period were exposed to a series of conditions in which the effects of antecedent and consequent events on SIB were examined systematically by way of multielement, reversal, or combined designs. Data were collected during approximately 4,000 experimental sessions (1,000 hr), with the length of assessment for individuals ranging from 8 to 66 sessions (M = 26.2) conducted over 2 to 16.5 hr (M = 6.5). Differential or uniformly high responding was observed in 145 (95.4%) of the cases. Social-negative reinforcement (escape from task demands or other sources of aversive stimulation) accounted for 58 cases, which was the largest proportion of the sample (38.1%). Social-positive reinforcement (either attention or access to food or materials) accounted for 40 (26.3%) of the cases, automatic (sensory) reinforcement accounted for 39 (25.7%), and multiple controlling variables accounted for 8 (5.3%). Seven sets of data (4.6%) showed either cyclical or inconsistent patterns of responding that were uninterpretable. Overall results indicated that functional analysis methodologies are extremely effective in identifying the environmental determinants of SIB on an individual basis and, subsequently, in guiding the process of treatment selection. Furthermore, an accumulation of assessment data from such analyses across a large number of individuals provides perhaps the most rigorous approach to an epidemiological study of behavioral function.     

THE RELATIVE MOTIVATIONAL PROPERTIES OF SENSORY AND EDIBLE REINFORCERS IN TEACHING AUTISTIC CHILDREN

We compared the effects of sensory and edible reinforcers on resistance to satiation in three autistic children while learning visual discrimination tasks. Within-subject designs were used to compare a single sensory reinforcer with a single edible reinforcer and to compare multiple sensory reinforcers with multiple edibles. Results indicated that multiple sensory reinforcers maintained responding over more trials than did multiple edible reinforcers; however, the use of single sensory reinforcers and single edibles resulted in about equal numbers of trials to satiation. Both multiple and single sensory reinforcers produced higher percentages of correct responses than edible reinforcers. The findings are discussed in terms of the advantages of sensory reinforcers in teaching autistic children.     

THE DEVELOPMENT AND FUNCTIONAL CONTROL OF READING-COMPREHENSION BEHAVIOR1

Reading comprehension, indicated by motor behavior and multiple-choice picture selection called for in written instructions, was taught to an autistic child using verbal prompts, modelling, and physical guidance. The child was rewarded for correct behaviors to training items; nonrewarded probes were used to assess generalization. Probable maintaining events were assessed through their sequential removal in a reversal design. Results showed: (a) following acquisition, performance was maintained at a near-100% level when candy, praise, attention, and training were removed, (b) absence of other persons was correlated with a marked decrease in performance, whereas their presence was associated with performance at near 100%, and (c) performance generalized to probes and across experimenters. Rewards, which may have been reinforcing during acquisition, did not appear necessary to maintain later performance. Instead, presence of others (a setting event) was demonstrated to have control over maintained performance.     

Examining stimuli paired with alternative reinforcement to mitigate resurgence in children diagnosed with autism spectrum disorder and pigeons

In two laboratory experiments, we examined whether stimuli paired with alternative reinforcers could mitigate resurgence of a previously reinforced target response with pigeons (Experiment 1) and children diagnosed with Autism Spectrum Disorder (Experiment 2). In Phase 1, we arranged food reinforcement according to a variable-ratio schedule for engaging in a target response. In Phase 2, we arranged extinction for target responding and differentially reinforced alternative responding according to a fixed-ratio schedule, with every alternative-reinforcer delivery paired with a change in keylight color (Experiment 1) or automated verbal (praise) statement (Experiment 2). In Phase 3, we assessed resurgence during extinction of target and alternative responding in the presence versus absence of continued presentation of the paired stimulus. Despite variation across sessions, resurgence on average was lower when continuing to present the paired stimuli in all pigeons and children while maintenance of alternative responding did not differ between assessments. These findings indicate that stimuli paired with alternative reinforcement can modestly decrease resurgence, but further examination of their efficacy and a better understanding of the underlying processes are necessary before they can be recommended for clinical use in reducing resurgence of clinically relevant problem behavior.     

SETTING GENERALITY AND STIMULUS CONTROL IN AUTISTIC CHILDREN1

This study was designed to assess the transfer of treatment gains of autistic children across settings. In the first phase, each of 10 autistic children learned a new behavior in a treatment room and transfer to a novel extra-therapy setting was assessed. Four of the 10 children showed no transfer to the novel setting. Therefore, in the second phase, each child who failed to transfer participated in an analysis of stimulus control in order to determine the variables influencing the deficit in transfer. Each of the four children who did not transfer were selectively responding to an incidental stimulus during the original training in the treatment room. Utilizing a reversal design, each of the four children responded correctly in the extra-therapy setting when the stimulus that was functional during training was identified and introduced into the extra-therapy setting. The extreme selective responding and the resulting bizarre stimulus control found are discussed in relation to the issue of setting generality of treatment gains.     

Teaching autistic children to respond to simultaneous multiple cues

A number of studies have shown that autistic children tend to learn new discriminations by responding to only a restricted number of available cues and that this may be responsible for some of their abnormal behavior. Therefore, this investigation assessed the feasibility of teaching autistic children to respond to multiple cues. The results showed that four autistic children could learn a conditional discrimination requiring them to discriminate a multiple-cue complex from each of its two component cues. However, the autistic children did not learn this discrimination in the same manner as normal children. In the early trials, the autistics responded at a higher level to one of the two component cues. Only after many trials did the autistics respond equally on the basis of both component cues. The results of an initial attempt to teach a general set to respond to multiple cues showed that, when an autistic child was taught a series of successive conditional discriminations, the child eventually learned a set to approach new discriminations by responding equally on the basis of both component cues. The results are discussed in terms of understanding and treating autistic children's abnormal development.     

Interactions between the effects of food and water motivating operations on food‐ and water‐reinforced responding in mice

Two experiments examined interactions between the effects of food and water motivating operations (MOs) on the food‐ and water‐reinforced operant behavior of mice. In Experiment 1, mice responded for sucrose pellets and then water reinforcement under four different MOs: food deprivation, water deprivation, concurrent food and water deprivation, and no deprivation. The most responding for pellets occurred under food deprivation and the most responding for water occurred under water deprivation. Concurrent food and water deprivation decreased responding for both reinforcers. Nevertheless, water deprivation alone increased pellet‐reinforced responding and food deprivation alone likewise increased water‐reinforced responding relative to no deprivation. Experiment 2 demonstrated that presession food during concurrent food and water deprivation increased in‐session responding for water relative to sessions where no presession food was provided. Conversely, presession water during concurrent food and water deprivation did not increase in‐session responding for pellets. These results suggest that a) the reinforcing value of a single stimulus can be affected by multiple MOs, b) a single MO can affect the reinforcing value of multiple stimuli, and c) reinforcing events can also function as MOs. We consider implications for theory and practice and suggest strategies for further basic research on MOs.     

INCREASING SPONTANEOUS PLAY BY SUPPRESSING SELF-STIMULATION IN AUTISTIC CHILDREN1

Appropriate play with toys was studied in two autistic children with high occurrences of self-stimulatory behavior. Each child participated in the experimental sessions in an A-B-A design, where “A” refers to baseline sessions and “B” refers to self-stimulation suppression sessions. It was found that: (a) during the baseline sessions, the children exhibited low levels of play and high levels of self-stimulatory behavior; (b) the per cent of unreinforced, spontaneous, appropriate play increased when self-stimulatory behavior was suppressed; and (c) when the suppression of self-stimulation was discontinued, the per cent of self-stimulation and that of appropriate play approached their presuppression levels. These results seem particularly significant because they identify a set of conditions under which spontaneous appropriate behavior, uncommon in autistic children, occurs at an increased level.     

Behavioral contrast and generalization across settings in the treatment of autistic children

Previous research on the generalization of treatment gains across settings has typically focused on the question of whether generalization occurs or does not occur. However, the experimental literature suggests another possibility: that behavioral contrast may occur in extra-therapy settings if the reinforcement procedures in the therapy setting are highly discriminable from those in other settings. Therefore, this investigation was designed to systematically assess whether: (1) a highly discriminable treatment procedure in one setting would produce a behavioral contrast effect in other unmanipulated settings; and (2) such contrast-like trends could be eliminated if initially different reinforcement procedures in two settings were subsequently made similar. The results for the eight autistic children who participated in this investigation showed that: (1) When very different reinforcement procedures (primary rewards or punishment in therapy settings, and no rewards or punishment in extra-therapy settings) were in effect, the children showed contrast-like behavior changes in the untreated extra-therapy settings; and (2) such trends in responding could be eliminated, resulting in generalization of treatment gains, if the reinforcement procedures were subsequently made relatively similar in the two settings, even if the procedures consisted essentially of noncontingent reinforcement.     

Autoshaping of abnormal children

Three experimentally naive abnormal children were exposed to a terminal operant contingency, i.e., reinforcement was delivered only if the children pressed a panel during intervals when it was lighted. Despite the absence of both successive approximation and manual shaping, it was found that each child began to respond discriminatively within a small number of trials. These data replicated previous animal studies concerned with the phenomena of autoshaping and signal-controlled responding. It was also found, however, that one type of autoshaping, the classical conditioning procedure, had a powerful suppressive effect on discriminative responding. An experimental analysis that consisted of a combination of intrasubject reversal and multiple baseline designs established the internal validity of the findings. The finding of rapid acquisiton of signalcontrolled responding obtained with the initial procedure is suggested to have practical significance. The disruptive effects of the classical form of autoshaping are discussed in terms of negative behavioral contrast.Funding for this study and for the development of the computer-operated laboratory was provided by the USOE, Bureau of Education for the Handicapped, as a portion of Grant Number G007604305, sensory discrimination, generalization, and language training of autistic children, awarded to R. L. Blanton and C. W. Deckner. The authors would like to express their appreciation to John Halsell for his assistance in computer operations and data collection.     

Imitation of Self-Stimulation:

Three autistic children participated in single subject, reversal designs to compare the impact of over correction and adult imitation on self-stimulation. In addition to continuous 10-second observations of frequency of self-stimulation during 10 minute sessions, experimenter and observer also rated the child's mood, attention to the experimenter and quality of attention paid. The order of interventions was randomized fro each subject with baseline preceding each intervention. Although each child's response pattern was unique, the data showed systematic changes in rates of self-stimulation across conditions for two of the children with mean levels of self-stimulation declining during the over correction procedure and increasing during imitation. There were parallel changes in mood and attention with all three children appearing “happiest” and most attentive when their self-stimulatory behavior was imitated by the adult. These results raise interesting possibilities for using adult imitation as a vehicle for establishing a reinforcing relationship with the autistic child.     

Delayed Alternation to Non-Positional Cues in Chimpanzee

Three subjects were exposed to fixed-ratio schedules of reinforcement in a two-phase experiment. In the first phase, sessions were terminated after a fixed number of responses had been emitted. In the second phase, sessions were terminated after a fixed length of time (equivalent to the mean of session lengths when steady state responding occurred in Phase 1). A comparison of response rates showed higher rates for all subjects in Phase 2.     

Case study: Reinforcement control of assaultive behavior in a sensory impaired child

This clinical case study describes the residential treatment of severe assaultive behavior in a 13-year-old sensory impaired child using two methods of positive reinforcement. Only slight reductions in the frequency of assaults occurred when the child was reinforced for compliance with task demands. Control was established quickly when reinforcement for the absence of responding was programmed in the form of a differential reinforcement of other behavior (DRO) contingency. Treatment fading was accomplished by gradually decreasing the immediacy and frequency of reinforcement. Extended follow-up assessment revealed near-zero levels of responding.