Relative preferences for edible and leisure stimuli in children with autism: A replication in Italy

Several studies have found that edible items tend to displace leisure items in multiple-stimulus preference assessments for individuals with developmental disabilities. One recent study (Conine & Vollmer, 2019) included screen-based technology devices in assessments and found that food items were less likely to displace leisure items and in some cases leisure items totally displaced edible items. The purpose of our study was to conduct a replication of Conine and Vollmer in Italy to evaluate cultural differences in food and leisure preferences. Results of our study were similar: For 44% of participants, at least one leisure item ranked above all edible items and leisure items displaced all edible items for 28% of participants. Participants in the present study showed a higher preference for leisure items or toys that were not screen-based technology devices, suggesting there may be cultural variation in the types of leisure items that are preferred.     

EVALUATION OF A MULTIPLE-STIMULUS PRESENTATION FORMAT FOR ASSESSING REINFORCER PREFERENCES

We compared three methods for presenting stimuli during reinforcer-preference assessments: a paired-stimulus format (PS), a multiple-stimulus format in which selections were made with replacement (MSW), and a multiple-stimulus format in which selections were made without replacement (MSWO). Results obtained for 7 participants showed moderate to high rank-order correlations between the MSWO and PS procedures and a similar number of identified reinforcers. In addition, the time to administer the MSWO procedure was comparable to that required for the MSW method and less than half that required to administer the PS procedure. Subsequent tests of reinforcement effects revealed that some stimuli selected in the PS and MSWO procedures, but not selected in the MSW procedure, functioned as reinforcers for arbitrary responses. These preliminary results suggest that the multiple-stimulus procedure without replacement may share the respective advantages of the other methods.     

A replication of preference displacement research in children with autism spectrum disorder

The purpose of this paper was to replicate previous research on preference displacement with edible and leisure stimuli. In the present study, the experimenters evaluated preference displacement in 25 children with autism spectrum disorder using combined multiple stimulus without replacement preference assessments that consisted of highly preferred edible and leisure stimuli. In addition, the experimenters used a block randomization procedure to evaluate if assessment order influenced displacement outcomes. The experimenters observed patterns of complete displacement by edible stimuli for four participants and complete displacement by leisure stimuli for two participants; assessment order did not influence outcomes. The results and implications are discussed.     

DISPLACEMENT OF LEISURE REINFORCERS BY FOOD DURING PREFERENCE ASSESSMENTS

Identification of reinforcers for individuals with developmental disabilities is often based on the outcome of preference assessments in which participants make selections from among a variety of items. We determined the extent to which individuals might show a general preference for food items over leisure items during such assessments and whether leisure items that are “displaced” by food items might nevertheless function as reinforcers. Arrays consisting of food items only and then nonfood items only were presented separately to 14 participants and then were ranked to determine preference. The top selections from these initial assessments were subsequently combined in a third assessment, and preferences were again established. All but 2 participants showed a general preference for food items, such that selection of nonfood items in the combined arrays was displaced downward relative to selection of nonfoods in the nonfood-only arrays. Two of the participants were exposed to a condition in which a nonfood item was delivered contingent on the occurrence of an adaptive response, and increased rates of responding by both individuals were observed. Results are discussed in terms of limitations posed by using only food items as reinforcers and the resulting need to take precautionary measures when attempting to identify nonfood reinforcers.     

Relative preferences for edible and leisure stimuli in children with autism

Prior researchers have reported a tendency for individuals with developmental disabilities to select edible items more often than leisure items when those items are presented together in stimulus preference assessments. However, children with autism spectrum disorders (ASD), with whom many behavior analysts currently practice, are underrepresented in this body of literature. We conducted a replication of prior research with 26 children with ASD. Results indicated that edible items were more likely than leisure items to rank highly in our preference assessments, in concurrence with prior research. However, leisure items were also selected more often overall than in prior research, and significant individual variation was observed. These results suggest that preference assessments containing both edible and leisure stimuli can yield useful information for behavior analysts providing services to children with ASD, and the degree of preference for edible items noted in prior work may not be reflected in this contemporary population.     

TIME DELAY: A TECHNIQUE TO INCREASE LANGUAGE USE AND FACILITATE GENERALIZATION IN RETARDED CHILDREN

Institutional breakfast-serving procedures were manipulated to assess what effect changes in that aspect of the environment would have on requests for food. During baseline, six severely retarded children were required to pick up their food trays and return to their seats. The first manipulation, delaying the giving of the food tray for 15 seconds, served as a cue to evoke meal requests by three of the six children. Two of the remaining three required a model of an appropriate meal request (i.e., “Tray, please.”) at the end of the 15-second delay before they began requesting their meals. To evoke meal requests from the sixth child, an intensive training procedure, consisting of massed trials of delay and modeling, was required. Three different probes were administered to assess generalization across the people serving the meals, across mealtimes, and across both people and mealtimes. Typically, generalized responding in these new situations could be prompted by use of the 15-second delay procedure. Functional aspects of the delay procedure and its potential usefulness for evoking speech and facilitating generalization are discussed.     

EMERGENCE OF REINFORCER PREFERENCE AS A FUNCTION OF SCHEDULE REQUIREMENTS AND STIMULUS SIMILARITY

Tustin (1994) recently observed that an individual's preference for one of two concurrently available reinforcers under low schedule requirements (concurrent fixed-ratio [FR] 1) switched to the other reinforcer when the schedule requirements were high (concurrent FR 10). We extended this line of research by examining preference for similar and dissimilar reinforcers (i.e., those affecting the same sensory modality and those affecting different sensory modalities). Two individuals with developmental disabilities were exposed to an arrangement in which pressing two different panels produced two different reinforcers according to progressively increasing, concurrent-ratio schedules. When two dissimilar stimuli were concurrently available (food and a leisure item), no clear preference for one item over the other was observed, regardless of the FR schedules in effect (FR 1, 2, 5, 10, and 20). By contrast, when two similar stimuli were concurrently available (two food items), a clear preference for one item emerged as the schedule requirements were increased from FR 1 to FR 5 or FR 10. These results are discussed in terms of implications for conducting preference assessments and for selecting reinforcers to be used under training conditions in which response requirements are relatively high or effortful.     

Preference for leisure items over edible items in individuals with dementia: A replication

We replicated previous research in which adults with dementia tended to show a preference for leisure items over edible items when presented in the same array. Additionally, we conducted engagement analyses with the highest, middle, and lowest preference leisure items to determine whether relative preference corresponded to engagement in the natural environment. The most highly preferred stimulus for 6 out of 7 participants was a leisure item, and for each of those six the top 3 preferred stimuli were leisure stimuli. For 4 participants, the most preferred stimulus also produced the longest duration of engagement. We discuss the issues we encountered when conducting preference assessments with adults with intact vocal verbal repertoires, and suggest potential explanations for the displacement of edibles by leisure stimuli in older adults with dementia.     

The effects of establishing operations on preferences for tangible items

Researchers have demonstrated that both deprivation and satiation can affect the outcome of preference assessments for food. In the current study, paired-stimulus preference assessments for tangible items were conducted under three conditions: control, deprivation, and satiation. Three persons with developmental disabilities and 3 typically developing preschool children served as participants. The results demonstrated that deprivation and satiation influenced the outcome of preference assessments of leisure items or toys.     

Evaluation of a brief multiple-stimulus preference assessment in a naturalistic context

We evaluated a brief multiple-stimulus preference assessment within the context of an early intervention program for 3 children who had been diagnosed with autism. Subsequent curriculum-based reinforcer evaluations confirmed the predictions of the preference assessments. In addition, eight additional preference assessments that were conducted over a period of 1 month indicated generally stable preferences for 2 of the 3 participants.     

Relative judgment seems to be the key: revisiting the Beck effect

In multiple-stimulus presentation, orientation disparity has been known to be more discriminable than disparity in line arrangement (e.g., J. Beck, 1972). The source of the effect and its locus were studied in 7 experiments. In different experiments a discrimination between an upright T and either a tilted T or an L, or a discrimination between a tilted T and an L, was required, either in a single stimulus presentation or in the context of upright Ts. Number of stimuli, location uncertainty, and adjacency between stimuli were manipulated. The results indicated that the effect is insensitive to these factors, which is incommensurate with predictions from several accounts of the effect. All the effect requires is that disparate stimuli are simultaneously presented, suggesting that relative judgment is a necessary condition for its manifestation. The effect surfaces when the task calls for procedures based on perception of homogeneity or salience.     

OBSERVATION AND COMPARISON OF MEALTIME BEHAVIORS IN A SAMPLE OF CHILDREN WITH AVOIDANT/RESTRICTIVE FOOD INTAKE DISORDERS AND A CONTROL SAMPLE OF CHILDREN WITH TYPICAL DEVELOPMENT

Despite widespread use of behavioral observations to evaluate child feeding behaviors in research and clinical practice, few studies have comprehensively characterized mealtimes or identified features that differentiate children with and without disordered feeding; these were the aims of the current study. Mealtime observations were conducted for 18 children with avoidant restrictive food intake disorder (ARFID) and 21 typically developing children. Observations were coded inductively, and associations between disorder and observed mealtime actions were examined. Most behaviors were observed across both clinical and nonclinical mealtimes, and many did not differ in frequency between children with and without ARFID. However, significant group differences were observed in the frequencies of behaviors relating to food intake, visual and physical engagement with feeding, and movement during mealtimes. The comparability of behaviors across clinical and nonclinical groups suggests that eating behaviors exist on a continuum from “normal” to “abnormal,” with group differences relating to frequency rather than type of behavior. The behavioral differences observed in this study suggest that identification of children with ARFID should focus on child engagement with food and restlessness during mealtimes. Reliance on emotional and escape‐maintained behaviors will lead to underrecognition of families in need of clinical support.     

Duration-based measures of preference for vocational tasks

We compared results from two preference assessments with data on extended performance of vocational tasks by 4 participants with developmental disabilities. All participants engaged in one task exclusively when seven tasks were available concurrently during a 5-min multiple-stimulus assessment. By contrast, all participants exhibited high levels of engagement in most tasks when the tasks were presented singly for 5 min, and these data showed a high degree of correspondence with those obtained during extended (60-min) vocational assessments.     

An examination of stimulus technology level and preference displacement during multiple stimulus without replacement preference assessments

Researchers have observed that preference for edible items may displace preference for leisure items when items from the stimulus classes are assessed together within multiple stimulus without replacement (MSWO) preference assessments. The current study extends previous research by examining patterns of preference and displacement when assessing preference for high-tech and low-tech leisure items. We conducted three separate MSWO preference assessments; one assessing low-tech items, another assessing high-tech items, and a combined assessment (using the top four high- and low-tech items from the previous assessments) to test for displacement. Preference for high-tech items fully or partially displaced preference for low-tech items in five of eight participants. We then conducted concurrent and single operant reinforcer assessments using the highly preferred high-tech and low-tech items. Reinforcer assessment results demonstrated similar levels of responding for the highest preferred high-tech and low-tech items, indicating that combining high- and low-tech items within preference assessments may influence the validity of results.     

Compounding of discriminative stimuli correlated with chained and multiple schedules

In studies of stimulus compounding (1) the stimuli are presented randomly, (2) primary reinforcement is correlated with each stimulus, (3) a specific response is emitted during each stimulus, and (4) the response is necessary to produce the reinforcer. The present experiments assessed the importance of these procedures by (1) presenting light and tone stimuli in fixed order, (2) removing reinforcement (food) during one stimulus, (3) preventing the response (lever pressing) from being emitted, and (4) eliminating the contingency between lever pressing and food. These variables were presented in various combinations within the context of chained and multiple schedules. When the stimuli were combined in the schedule component correlated with each stimulus, the frequency of lever pressing increased in most instances (additive summation). This suggests that the effect of combining stimuli was not closely tied to the specific procedures used in previous experiments. However, presenting the stimuli in a fixed order did have an effect: the level of responding to the compound was generally greatest when the stimuli were combined in the component correlated with the higher frequency of lever pressing to the single stimulus. Additive summation failed to occur consistently when response-independent food was correlated with each stimulus, and when both lever pressing and food were eliminated during one stimulus.     

An Evaluation of a Brief Multiple-Stimulus Without Replacement Preference Assessment Conducted in an Electronic Pictorial Format

We compared the results of a brief electronic pictorial multiple-stimulus without replacement (EP-MSWO) preference assessment to a brief tangible MSWO preference assessment in five children with autism. Results of both assessments yielded a match between high preferred (HP) toys for four participants and low preferred toys for three participants. The overall correlation between assessments across participants was strong and statistically significant (ρ = .67, p < .01). A reinforcer assessment conducted with three participants confirmed HP toys identified in the EP-MSWO functioned as reinforcers.     

EVALUATION OF THE MULTIPLE-STIMULUS WITHOUT REPLACEMENT PREFERENCE ASSESSMENT METHOD USING ACTIVITIES AS STIMULI

The current study examined the accuracy of the multiple-stimulus without replacement (MSWO) preference assessment for identifying preferred common classroom activities as reinforcers with children with behavioral disorders. The accuracy of predictions from the MSWO regarding high, medium, and low stimulus preference was tested by providing contingent access to activities for completing math problems within an independent seatwork format. Overall, there was an interaction effect between preference ranking (high, medium, or low) and number of problems completed. The results confirm and extend previous findings regarding the accuracy of predictions with the MSWO. The findings also reveal, however, some individual differences that may account for instances in which student behavior did not conform to predictions of stimulus preference assessments.     

Long‐term stability of edible preferences in individuals with developmental disabilities

Multiple stimulus without replacement (MSWO) preference assessments were used to examine the stability of preference hierarchies in eight individuals with developmental disabilities. In Study 1, preference assessments using edible items were conducted 6 months apart; in Study 2, assessments were conducted 12 months apart. As in previous studies analyzing preference stability, individual differences in stability were found in both studies. However, mean rank order coefficients across participants revealed interesting findings in both comparisons. Generally, preference for edible items, particularly the most and least preferred stimuli, was more stable across time than has been found in other research conducted with leisure items. Stability was greater when only 6 months lapsed between assessments. Moreover, for three of the eight participants, rank order coefficients were significant across both studies indicating the possibility that some individuals may tend toward more stable preferences. Copyright © 2007 John Wiley & Sons, Ltd.     

Increasing accurate preference assessment implementation through pyramidal training

Preference assessments directly evaluate items that may serve as reinforcers, and their implementation is an important skill for individuals who work with children. This study examined the effectiveness of pyramidal training on teachers' implementation of preference assessments. During Experiment 1, 3 special education teachers taught 6 trainees to conduct paired-choice, multiple-stimulus without replacement, and free-operant preference assessments. All trainees acquired skills necessary to implement preference assessments with 90% or greater accuracy during the training sessions and demonstrated generalization of skills to their classrooms or clinic. During Experiment 2, 5 teachers who served as trainees in Experiment 1 trained 18 preschool teachers. All preschool teachers met the mastery criterion following training. Training teachers to implement preference assessments may increase teachers' acceptance and use of behavior-analytic procedures in school settings.     

An evaluation of emerging preference for non‐preferred foods targeted in the treatment of food selectivity

Several studies have shown that the acquisition of food consumption does not occur until after escape prevention is implemented. However, the mechanism responsible for the maintenance of food consumption may be due to participants contacting the reinforcing properties of food targeted during intervention such that the food naturally reinforces food consumption. The present study extended the literature on feeding disorders by conducting pre‐ and post‐treatment preference assessments to determine if preference for non‐preferred foods (NPFs) had developed after exposure to a treatment comparison of sequential and simultaneous food presentation; presentation methods were implemented alone and combined with escape prevention in the form of a non‐removal of the spoon (NRS) procedure. Results for three participants with food selectivity indicated that preference for NPFs developed after being exposed to those foods during either treatment sessions or generalization probes. Copyright © 2010 John Wiley & Sons, Ltd.