An Empirical Analysis of Interspersal Research: Evidence, Implications, and Applications of the Discrete Task Completion Hypothesis

Because assignment completion is often reinforced, researchers have posited that when students work on assignments with many discrete tasks (e.g., 20 mathematics problems), that each completed discrete task may be a conditioned reinforcer (e.g., Skinner et al., 1999). If the discrete task completion hypothesis is accurate, then relative task completion rates should influence choice behavior in the same manner as relative rates of reinforcement. In the current study, previous interspersal research was combined across experiments and regression analysis revealed a linear relationship between relative problem completion rates (RPCR) and choice in accordance with the matching law (Herrnstein, 1961, 1970). These results support the discrete task completion hypothesis and suggest that interspersing additional brief tasks enhances interval schedules of reinforcement. Theoretical and applied implications of the current study and the discrete problem completion hypothesis are discussed and directions for future research are provided.     

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.     

Increasing on‐task behavior of an adolescent with autism using momentary differential reinforcement

Compliance is often defined as the completion of a discrete task specified by a preceding instruction. However, compliance could also require the completion of a cluster of tasks, such as cleaning a room, getting ready for bed, or doing homework. We conducted this study to determine if a momentary differential reinforcement schedule would increase the on‐task behavior of an adolescent with autism. The momentary differential reinforcement involved repeated momentary supervision checks, with tokens delivered for appropriate task engagement at that moment. The participant completed math worksheets and remained on task as the number of supervisions was faded from one every 30 s to one every 5 min.     

COMPETITION BETWEEN POSITIVE AND NEGATIVE REINFORCEMENT IN THE TREATMENT OF ESCAPE BEHAVIOR

We compared the effects of reinforcing compliance with either positive reinforcement (edible items) or negative reinforcement (a break) on 5 participants' escape-maintained problem behavior. Both procedures were assessed with or without extinction. Results showed that compliance was higher and problem behavior was lower for all participants when compliance produced an edible item rather than a break. Treatment gains were achieved without the use of extinction. Results are discussed regarding the use of positive reinforcement to treat escape behavior.     

Further examination of factors that influence preference for positive versus negative reinforcement

Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer during treatment (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Lalli et al., 1999). However, a number of variables may influence choice between concurrently available forms of reinforcement. An analogue for treatment situations in which positive reinforcement for compliance is in direct competition with negative reinforcement for problem behavior was used in the current study to evaluate several variables that may influence choice. Participants were 5 children who had been diagnosed with developmental disabilities and who engaged in problem behavior maintained by escape from demands. In the first phase, the effects of task preference and schedule of reinforcement on choice between a 30-s break and a high-preference food item were evaluated. The food item was preferred over the break, regardless of the preference level of the task or the reinforcement schedule, for all but 1 participant. In the second phase, the quality of the break was manipulated by combining escape with toys, attention, or both. Only 1 participant showed preference for the enriched break. In the third phase, choice of a medium- or low-preference food item versus the enriched break was evaluated. Three of 4 participants showed preference for the break over the less preferred food item. Results extend previous research by identifying some of the conditions under which individuals who engage in escape-maintained behavior will prefer a food reinforcer over the functional one.     

Teacher-control versus student-control over choice of task and reinforcement for students with severe behavior problems

Increasing self-control for students with severe disabilities is an important step toward normalization. The classroom is one setting in which opportunities for self-control can be created. The effects of teacher-control versus student-control over academic task and reinforcement selection were evaluated for three 11-to 13-year-old males with severe behavior problems. Under student-control conditions students were able to select rewards and tasks from lists generated by the teacher; in the teacher-control conditions, the teacher selected rewards and tasks but attempted to make similar selections to those made by the students. An alternating treatments design was implemented. In Phase 1, task completion was the target behavior; in Phase 2 task accuracy was the target behavior. Task performance improved when the student, rather than the teacher, had control over task assignments and choice of reinforcement. While either student control of reinforcement or student control of task assignment resulted in higher performance than did teacher-control, the most effective instructional situation was the two procedures combined. This effect was apparent even when students and teachers selected the same tasks and the same reinforcers. Implications for increasing student-control over some classroom decisions are discussed.deceased.     

Effects of Interspersed Brief Problems on Students' Endurance at Completing Math Work

An alternating treatments design was used to compare the effects of baseline, interspersed brief problems, and interspersed brief problems plus token reinforcement on students' endurance while completing math worksheets. By pairing the completion of brief problems with token reinforcement, the role of problem completion as a conditioned reinforcer was examined consistent with the discrete task completion hypothesis. Four 5th grade students who were low achieving in math participated. Each day the students completed a stack of math worksheets containing 3-digit by 3-digit addition problems with or without interspersed single-digit problems for 10 min. Dependent measures included total digits correct per session and during each min of the 10 min work period (i.e., a measure of endurance). Results indicated that total digits correct per session was highest during the interspersal plus reinforcement condition followed by interspersal and then baseline for three of the four students. In addition, both interspersal conditions resulted in greater endurance than baseline. Limitations of the current study and implications for increasing students' persistence on classroom tasks are discussed.     

Accuracy versus speed in the generalized effort of learning-disabled children

Reinforcement of effortful performance in a given academic task has been found to increase the subsequent performance of other academic tasks. The learned-effort hypothesis assumes that individuals learn which dimensions of task performance are correlated with reinforcement of high effort, and generalize across tasks. Therefore, reinforcement of increased effort in a given dimension of one task should result in greater generalized effort in the same dimension of transfer performance than in another dimension. In accord with this view, preadolescent learning-disabled students who received points for high reading accuracy subsequently produced more accurate drawings and stories than did students whose points had been based upon high reading speed or upon mere completion of the reading task. Students who received points for high reading speed subsequently constructed stories more quickly than did children whose points had been based upon high reading accuracy or upon reading-task completion. Consistent with the more explicit and frequent feedback for accuracy than for speed in most academic tasks, generalized accuracy was much more durable than generalized speed.     

STIMULUS CHARACTERISTICS WITHIN DIRECTIVES: EFFECTS ON ACCURACY OF TASK COMPLETION

Three experiments were conducted in an outpatient setting with young children who had been referred for treatment of noncompliant behavior and who had coexisting receptive language or receptive vocabulary difficulties. Experiment 1 studied differential responding of the participants to a brief hierarchical directive analysis (least‐to‐most complex stimulus prompts) to identify directives that functioned as discriminative stimuli for accurate responding. Experiment 1 identified distinct patterns of accurate responding relative to manipulation of directive stimulus characteristics. Experiment 2 demonstrated that directives identified as effective or ineffective in obtaining stimulus control of accurate responding during Experiment 1 continued to control accurate responding across play activities and academic tasks. Experiment 3 probed effects of the interaction between the type of directive (effective vs. ineffective) and the reinforcement contingency (differential reinforcement for attempts vs. differential reinforcement for accurate responses) on accurate task completion and disruptive behavior. Results suggested that behavioral escalation from inaccurate responding to disruptive behavior occurred only when ineffective directives were combined with differential reinforcement for accurate task completion. The overall results are discussed in terms of developing a methodology for identifying stimulus characteristics of directives that affect accurate responding.     

An evaluation of persistence of treatment effects during long-term treatment of destructive behavior

Eight young children who displayed destructive behavior maintained, at least in part, by negative reinforcement received long‐term functional communication training (FCT). During FCT, the children completed a portion of a task and then touched a communication card attached to a microswitch to obtain brief breaks. Prior to and intermittently throughout FCT, extinction probes were conducted within a withdrawal design in which task completion, manding, and destructive behavior were placed on extinction to evaluate the relative persistence of appropriate and destructive behavior over the course of treatment. FCT continued until appropriate behavior persisted and destructive behavior failed to recur at baseline levels during extinction probes. The completion of FCT was followed by four challenges to the persistence of treatment effects conducted within mixed‐ or multiple‐schedule designs: (a) extended extinction sessions (from 5 to 15 min), (b) introduction of a novel task, (c) removal of the microswitch and communication card, and (d) a mixed schedule of reinforcement in which both appropriate and destructive behavior produced reinforcement. The results showed that although FCT often resulted in quick reductions in destructive behavior and increases in appropriate behavior, destructive behavior often recurred during the extinction probes conducted during the initial treatment. When the effects of treatment persisted during the extinction probes, the remaining challenges to treatment effects resulted in only mild to moderate disruptions in behavior. These results are consistent with the quantitative predictions of behavioral momentum theory and may provide an alternative definition of maintenance as constituting behavioral persistence.     

Transfer of persistence across behaviors

Two experiments tested the applicability to human beings of findings with animals that the number of performances required for the reinforcement of one behavior affects the subsequent effort expended in other instrumental behaviors. In the first experiment, adult depressed psychiatric patients worked on a sorting task for the approval of a staff psychologist. The time spent and the work completed were increased by prior approval from a ward attendant for each completion of several custodial tasks, as compared to the ward attendant's approval for each completion of a single task or a no-pretreatment control condition. In the second experiment, preadolescent learning-disabled students who were required to read and spell correctly a greater number of words per reward token later spent more time and completed more work for reward tokens in mathematics, and handwriting. Two alternative interpretations of these results are evaluated: (a) The degree of accustomed effort per reinforcer becomes a learned component of behavior, or (b) high effort increases the habituation of frustration-produced disruptive responses. The results suggest that individual differences in general persistence may arise, in part, from an accumulation of effort training in the natural environment.     

An analysis of stereotypy during prevocational instruction of an adolescent with severe mental retardation

An adolescent with severe retardation was observed during participation in several vocational tasks. The vocational tasks were comprised of repeating sequences of work-related responses. Across two experiments, conditions that are typical in the training of vocational tasks in special education and adult vocational programs were manipulated and the effects of these conditions on rates of vocational sequences completed and rates of stereotypic behavior were assessed. In Experiments 1 and 2, the adolescent was reinforced with a food item following the completion of vocational sequences under two alternating reinforcement contingencies. Under one contingency, the adolescent performed with frequent errors and under the other, often performed without errors. In Experiment 3, the adolescent participated with another student in a different vocational task on alternating days and in an alternating sequence of work conditions in each task. In one condition, both adolescents had vocational materials nearly continuously present and the teacher prompted and reinforced both adolescents as needed. In the other condition, the vocational materials were presented to the adolescents on an alternating basis, and the teacher prompted and reinforced first one and then the other. Across both experiments, increased competence reflected as high rate, error free, and consistent vocational performances were associated with low rates of stereotypic behavior when compared to conditions with less competent performances, and with leisure periods in Experiment 3. © 1997 John Wiley & Sons, Ltd.     

Effects of Signaled Positive Reinforcement on Problem Behavior Maintained by Negative Reinforcement

We evaluated the effects of providing positive reinforcement for task completion, signaled via the presence of a tangible item, on escape-maintained problem behavior displayed by three typically developing children during one-time 90-min outpatient evaluations. Brief functional analyses of problem behavior, conducted within a multielement design, identified negative reinforcement. Treatment, conducted within a nonconcurrent multiple baseline with reversal design, consisted of a signal for positive reinforcement while continuing to permit escape for problem behavior, thus creating a competition between positive and negative reinforcement. For all participants, problem behavior decreased.     

TASK DIFFICULTY AND ABERRANT BEHAVIOR IN SEVERELY HANDICAPPED STUDENTS

The influence of task difficulty on aberrant behavior was investigated with three severely handicapped students. Noticeably higher rates of problem behavior occurred in demand compared to no-demand conditions. In addition, there were higher rates of problem behaviors on difficult versus easy tasks. Both these findings were validated with visual discrimination and perceptual motor tasks. An errorless learning procedure effectively minimized errors and aberrant behavior in visual discrimination tasks but not in perceptual motor tasks. It was conceptualized that aberrant behavior was maintained by negative reinforcement contingencies. Difficult tasks were aversive to the children, who emitted aberrant responses to escape or avoid such tasks. By contrast, conditions in which no demands were made, easy tasks, and, in visual discrimination learning, errorless tasks, were less aversive and resulted in little or no problem behavior. Implications for reducing maladaptive behaviors through curricular modifications are discussed and contrasted to more traditional consequence manipulation approaches.     

REDUCTION OF SEVERE BEHAVIOR PROBLEMS IN THE COMMUNITY USING A MULTICOMPONENT TREATMENT APPROACH

Problem behavior often prevents community integration of people with developmental disabilities. Therefore, we evaluated a multicomponent approach for remediating problem behavior in public community settings (specifically, supermarkets). We selected treatments based on hypotheses about the variables controlling the problem behavior (hypothesis-driven model). The multicomponent intervention included choice making, embedding, functional communication training, building tolerance for delay of reinforcement, and presenting discriminative stimuli for nonproblem behavior. Treatment progress was monitored using measures of latency and task completion rather than traditional measures of frequency and time sampling. Results showed substantial increases in task completion and duration of time spent in supermarkets without problem behavior. Outcomes were socially validated by group-home staff and cashiers. We discuss how the intervention approach taken can resolve some of the issues involved in assessing, measuring, and treating problem behavior in the community.     

Finishing on time: When do predictions influence completion times?

People typically predict they will finish projects earlier than they do. Whereas previous research has examined the determinants of this prediction bias, the present research explored potential consequences for behavior. In particular, we examined whether and when task completion predictions influence actual completion times. In four experiments we used anchoring manipulations to induce participants to make relatively early or late task completion predictions, and then examined when they started and/or finished the target tasks. As hypothesized, the prediction manipulation influenced completion times under certain conditions defined by the nature of the target task. Manipulated predictions affected completion times of closed tasks, defined as tasks carried out within a single, continuous session but not of open tasks, defined as tasks requiring multiple work sessions. This implies that task completion predictions help to initiate action, but their impact diminishes over the course of extensive, multi-stage projects.     

Response acquisition under direct and indirect contingencies of reinforcement

We compared the effects of direct and indirect reinforcement contingencies on the performance of 6 individuals with profound developmental disabilities. Under both contingencies, completion of identical tasks (opening one of several types of containers) produced access to identical reinforcers. Under the direct contingency, the reinforcer was placed inside the container to be opened; under the indirect contingency, the therapist held the reinforcer and delivered it to the participant upon task completion. One participant immediately performed the task at 100% accuracy under both contingencies. Three participants showed either more immediate or larger improvements in performance under the direct contingency. The remaining 2 participants showed improved performance only under the direct reinforcement contingency. Data taken on the occurrence of "irrelevant" behaviors under the indirect contingency (e.g., reaching for the reinforcer instead of performing the task) provided some evidence that these behaviors may have interfered with task performance and that their occurrence was a function of differential stimulus control.     

REDUCING ESCAPE BEHAVIOR AND INCREASING TASK COMPLETION WITH FUNCTIONAL COMMUNICATION TRAINING,EXTINCTION AND RESPONSE CHAINING

The effects of functional communication training, extinction, and response chaining on 3 subjects' escape-maintained aberrant behavior were evaluated using a multielement design. Functional communication training consisted of teaching subjects a verbal response that was functionally equivalent to their aberrant behavior. Subjects initially were allowed to escape from a task contingent on the trained verbal response. In subsequent treatment phases, escape was contingent on the trained verbal response plus the completion of the specified number of steps in the task (response chaining). The number of steps was increased until a subject completed the task to obtain a break. Results showed that the treatment reduced rates of aberrant behavior and that the chaining procedure was effective in decreasing the availability of escape.     

THE RELATIVE INFLUENCE OF MOTIVATING OPERATIONS FOR POSITIVE AND NEGATIVE REINFORCEMENT ON PROBLEM BEHAVIOR DURING DEMANDS

Research has demonstrated the feasibility of using positive reinforcement to treat problem behavior maintained by negative reinforcement. This line of research was extended in the current study. A functional analysis (FA) was conducted that suggested problem behavior was maintained by positive and negative reinforcement. Following the FA, a demand analysis was conducted with three demand conditions: one that replicated the demand condition from the FA, one that included presession exposure to a preferred item, and another that included presession exposure to preferred items and access to those items during breaks from demands. Although problem behavior occurred in all three demand conditions, within session analyses showed that problem behavior ceased during breaks from demands only when they included access to preferred items. This finding suggests that the motivating operation responsible for evoking problem behavior did not decrease when only a break was provided. Subsequent functional communication training and treatment analysis showed that treatments based on positive reinforcement were effective at reducing problem behavior, but those based on a negative reinforcement hypothesis were not. Copyright © 2013 John Wiley & Sons, Ltd.     

A comparison of differential reinforcement procedures for treating automatically reinforced behavior

Children diagnosed with autism spectrum disorder (ASD) often exhibit stereotypy, which can be socially stigmatizing, interfere with daily living skills, and affect skill acquisition. We compared differential reinforcement of alternative behavior (DRA) and differential reinforcement of other behavior (DRO) when neither procedure included response blocking or interruption for (a) reducing stereotypy, (b) increasing task engagement, and (c) increasing task completion. DRA contingencies yielded superior outcomes across each measure when evaluated with 3 individuals with autism spectrum disorder.