The emergence of conditioned reinforcement from observation

We report an experiment in which observations of peers by six 3-5-year-old participants under specific conditions functioned to convert a small plastic disc or, for one participant, a small piece of string, from a nonreinforcer to a reinforcer. Prior to the observational procedure, we compared each participant's responding on (a) previously acquired performance tasks in which the child received either a preferred food item or the disc (string) for correct responses, and (b) the acquisition of new repertoires in which the disc (string) was the consequence for correct responses. Verbal corrections followed incorrect responses in the latter tasks. The results showed that discs and strings did not reinforce correct responses in the performance tasks, but the food items did; nor did the discs and strings reinforce correct responses in learning new repertoires. We then introduced the peer observation condition in which participants engaged in a different performance task in the presence of a peer who also performed the task. A partition blocked the participants from seeing the peers' performance. However, participants could observe peers receiving discs or strings. Participants did not receive discs or strings regardless of their performance. Peer observation continued until the participants either requested discs or strings repeatedly, or attempted to take discs or strings from the peers. Following the peer observation condition, the same performance and acquisition tasks in which participants had engaged prior to observation were repeated. The results showed that the discs and strings now reinforced correct responding for both performance and acquisition for all participants. We discuss the results with reference to research involving nonhuman subjects that demonstrated the observational conditioning of reinforcers.     

OBSERVATIONAL EFFECTS ON THE PREFERENCES OF CHILDREN WITH AUTISM

Children with an autism spectrum disorder (ASD) may play with limited objects or toys, making it difficult for teachers to identify reinforcers to use in teaching new skills. The goal of this study was to alter children's preferences from highly preferred toys to toys that were originally less preferred using an observational pairing procedure. Child participants observed a preferred adult playing with toys that were initially less preferred by the child. This intervention resulted in a shift in preference toward the item manipulated by the adult. Maintenance of the changed preference was idiosyncratic across participants. Results suggest a procedure for expanding the range of items that students with ASD will select.     

Establishing praise as a conditioned reinforcer: Pairing with one versus multiple reinforcers

Praise and other forms of attention may not function as reinforcers for the behavior of children with autism. Previous research demonstrated that contingently pairing praise with reinforcers (response stimulus) can establish praise as a conditioned reinforcer. We evaluated a procedure for establishing praise as a generalized conditioned reinforcer (pair praise with four reinforcers) and compared it with a procedure to establish praise as a conditioned reinforcer (pair praise with one reinforcer). We compared the two conditions in a reversal design with “praise” and “no programmed consequence” conditions rapidly alternated after pairing phases. With three out of five participants with autism, responding in the “pair‐with‐four” condition showed higher levels of responding or more increasing trends compared with that in “pair‐with‐one” condition. We also replicated previous contingent pairing research with two participants in a multiple baseline across participants design. A limitation was the absence of manipulating motivating operations in assessing the efficacy of praise as a generalized conditioned reinforcer. Nevertheless, these data contribute to the research on establishing praise as a reinforcer, and we recommend directions for future research.     

Using progressive ratio schedules to evaluate tokens as generalized conditioned reinforcers

The properties of operant reinforcers are dynamic and dependent on a number of variables, such as schedule and effort. There has been sparse research on the generalized conditioned properties of token reinforcement. We evaluated leisure items, edible items, and tokens using a progressive ratio schedule with three children with diagnoses of ASD and developmental delays. The highest break points occurred during the token reinforcement condition for two out of three participants, but response rates tended to be higher with edibles. We then evaluated the effects of presession access to edibles on the break points of edible items and tokens with two participants. Break points decreased only in the edible reinforcement condition, and the participants chose to work for leisure items rather than edibles when presession access to edibles was in place. These findings suggest that the tokens functioned as generalized conditioned reinforcers.     

Comparing the reinforcing efficacy of tokens and primary reinforcers

Token economies are one of the most commonly used behavior-analytic interventions. Despite literature supporting the use of tokens as tools for behavior change, little is known about the efficacy of tokens compared to that of the items for which they are exchanged. Results of previous research comparing the reinforcing efficacy of tokens and primary reinforcers have shown that both produce similar effects on responding. However, published findings have been confounded given the inclusion of primary reinforcers in the token-reinforcer test conditions. In this study, we established novel tokens as reinforcers. We then conducted a conditioned-reinforcer assessment using a tandem control to ensure that the tokens functioned as reinforcers. We used progressive-ratio schedules to compare the reinforcing efficacy of the tokens to high- and low-preference edibles that were also used as backup reinforcers. For both participants, we found that high-preference primary reinforcers maintained higher response frequencies than did tokens.     

The conditioned reinforcement of repeated acquisition

Three monkeys were trained to emit a chain of three responses on three separate levers in a set of six levers to obtain food. The chain producing food (correct chain) was changed each day. During a trial, a press on any lever produced a feedback stimulus; a press on a correct lever produced an additional distinctive stimulus; the third correct press produced a food pellet. Test sessions in which either the food or the distinctive stimuli were removed were interspersed with baseline sessions. In tests without food presentations, the subjects acquired the correct chain rapidly, with a level of accuracy comparable to baseline. Removing the distintive stimuli for either the first or second member of the correct chain greatly retarded acquisition of that member of the chain. Removing all distinctive stimuli often reduced accuracy throughout the chain to chance level, even though food was presented following each correct chain. These results were interpreted as evidence that the distinctive stimuli presented after correct responses functioned as conditioned reinforcers. Reductions in accuracy following an omitted distinctive stimulus indicated that they were also discriminative stimuli for correct responding in their presence.     

Antecedent Selection: Comparing Simplified and Typical Verbal Antecedents for Children with Autism

This study measured the differential effects of simplified and typical verbal antecedents on acquisition of picture discriminations for four preschool children with autism. During baseline probes, participants emitted no correct selection responses to pictures of common stimuli during either simplified or typical verbal antecedent conditions. Using an adapted alternating treatments design during training, instructors presented a simplified verbal antecedent (i.e., “Give me car”) or a typical verbal antecedent (i.e., “One of these is a car. Which one is it?”), and differentially reinforced participants’ correct selection responses given the target picture and two non-targets. Results showed that one participant emitted more correct responses during simplified than typical verbal antecedent conditions, one participant emitted more correct responses during typical than simple verbal antecedent conditions, and there was no clear difference for the other two participants.     

Mediating Access to Headsprout<Superscript>®</Superscript> Early Reading for Children with Autism Spectrum Disorders

Many children with autism spectrum disorder (ASD) require instructional programs that simultaneously address academic content, interfering behavior, and potential gaps in prerequisite skills for a given curriculum. This study examined the impact of an intervention package consisting of contingent reinforcement and match-to-sample training on the independent progression of 3 children with ASD through Headsprout^® Early Reading (HER), a behavior analytic online reading program. A multiple probe across participants design was used to examine the effects of the intervention package on participants’ correct interactions per minute and total episodes completed. Transfer of training to oral reading of companion print books was also assessed. All participants demonstrated an increase in correct interactions per minute. Two participants learned to independently complete a HER episode each day and could orally read companion print books. The results suggest individualized behavior analytic programs can support the use of HER as a computer-based reading program for some children with ASD.     

Human symbolic matching-to-sample performance: Effects of reinforcer and sample-stimulus probabilities

Four experiments, each with 6 human subjects, varied the distribution of reinforcers for correct responses and the probability of sample-stimulus presentation in symbolic matching-to-sample procedures. Experiment 1 held the sample-stimulus probability constant and varied the ratio of reinforcers obtained for correct responses on the two alternatives across conditions. There was a positive relation between measures of response bias and the ratio of reinforcers. Experiment 2 held the ratio of reinforcers constant and varied the sample-stimulus probability across conditions. Unlike previous studies that used pigeons as subjects, there was a negative relation between bias and the ratio of sample-stimulus presentations. In Experiment 3, the sample-stimulus probability and the reinforcer ratio covaried across conditions. Response bias did not vary systematically across conditions. In Experiments 1 to 3, correct responses were reinforced intermittently. Experiment 4 used the same procedure as Experiment 3, but all correct responses now produced some scheduled consequence. There was a positive relation between response bias and the ratio of reinforcers. The results suggest that human performance in these tasks was controlled by both the relative frequency of reinforced responses and the relative frequency of nonreinforced responses.     

ON THE RELATIVE REINFORCING EFFECTS OF CHOICE AND DIFFERENTIAL CONSEQUENCES

Research on the reinforcing effects of providing choice-making opportunities to individuals with developmental disabilities (i.e., allowing them to choose reinforcers or tasks) has produced inconsistent results, perhaps because the mechanisms underlying such effects remain unclear. Choice may produce a reinforcement effect because it is correlated with differential consequences (i.e., choice may increase one's access to higher preference stimuli), or it may have reinforcement value independent of (or in addition to) the chosen stimulus. In Experiment 1, we used a concurrent-operants arrangement to assess preference for a choice condition (in which participants selected one of two available reinforcers) relative to a no-choice condition (in which the therapist selected the same reinforcers on a yoked schedule). All 3 participants preferred the choice option. In Experiment 2, we altered the schedules so that the participant selected one of two lower preference reinforcers in the choice condition, whereas the therapist selected a higher preference stimulus for the participant either half or all of the time in the no-choice condition. Participants typically allowed the therapist to select reinforcers for them (i.e., they allocated responding to the no-choice condition) when it resulted in greater access to higher preference stimuli.     

PARAMETRIC ANALYSIS OF PRESESSION EXPOSURE TO EDIBLE AND NONEDIBLE STIMULI

We assessed the effects of individually defined small, medium, and large periods of presession access to edible and nonedible reinforcers on response rates during sessions in which responding produced access to identical reinforcers. Any presession access to an edible reinforcer decreased response rates for 1 participant, and small and medium periods of presession access to nonedible reinforcers resulted in similar or increased response rates for 2 participants.     

EFFECTS OF POINT‐LOSS PUNISHERS ON HUMAN SIGNAL‐DETECTION PERFORMANCE

Three experiments using human participants varied the distribution of point‐gain reinforcers or point‐loss punishers in two‐alternative signal‐detection procedures. Experiment 1 varied the distribution of point‐gain reinforcers for correct responses (Group A) and point‐loss punishers for errors (Group B) across conditions. Response bias varied systematically as a function of the relative reinforcer or punisher frequencies. Experiment 2 arranged two conditions — one where an unequal ratio of reinforcement (5:1 or 1:5) was presented without punishment (R‐only), and another where the same reinforcer ratio was presented with an equal distribution of point‐loss punishers (R+P). Response bias was significantly greater in the R‐only condition than the R+P condition, supporting a subtractive model of punishment. Experiment 3 varied the distribution of point‐gain reinforcers for correct responses across four unequal reinforcer ratios (5:1, 2:1, 1:2, 1:5) both without (R‐only) and with (R+P) an equal distribution of point‐loss punishers for errors. Response bias varied systematically with changes in relative reinforcer frequency for both R‐only and R+P conditions, with 5 out of 8 participants showing increases in sensitivity estimates from R‐only to R+P conditions. Overall, the results indicated that punishers have similar but opposite effects to reinforcers in detection procedures and that combined reinforcer and punisher effects might be better modeled by a subtractive punishment model than an additive punishment model, consistent with research using concurrent‐schedule choice procedures.     

Preference for unreliable reinforcement in children with mental retardation: the role of conditioned reinforcement

We examined the effects of conditioned reinforcement on children's choice between reliable (100%) and unreliable (50%) reinforcement under various stimulus conditions in a concurrent-chains procedure. The study was conducted across three experiments. Experiments 1 and 2 were conducted under conditions similar to basic laboratory work and consisted of participants selecting from one of two black boxes (placed on a table) that were correlated with different reinforcement schedules. In Experiment 3, we assessed a participant's preference for unreliable reinforcement during conditions in which the target responses were aggression and mands. Results of the three experiments showed that the participants preferred unreliable reinforcement under certain conditions. Findings are discussed regarding the role of specific stimuli (i.e., items correlated with a reinforcement schedule, adult reactions) as conditioned reinforcers and how they may influence children's preference for a response (e.g., aggression, self-injury) that produces reinforcement on a leaner schedule than a socially desirable response (e.g., mands).     

ACQUISITION OF INTRAVERBAL BEHAVIOR: TEACHING CHILDREN WITH AUTISM TO MAND FOR ANSWERS TO QUESTIONS

Four boys with autism were taught via echoic prompting and constant prompt delay to mand for answers to questions by saying “I don't know please tell me” (IDKPTM). This intervention resulted in acquisition of the IDKPTM response for all 4 participants and in acquisition of correct answers to most of the previously unknown questions for 2 participants. For 1 participant, tangible reinforcement resulted in increased frequency of correct answers, and direct prompting of correct answers was eventually conducted for the final participant. The IDKPTM response generalized to untargeted unknown questions with 3 participants. Results of person and setting generalization probes varied, but some generalization eventually occurred for all participants following additional training or interspersal of probe trials with training trials.     

The effects of paired kinesthetic movements on literacy skills acquisition with preschoolers

Students who fail to acquire foundational literacy skills during preschool are more likely to read below grade level average in elementary school and are at a heightened risk for future school failure, poverty, early mortality, and crime. The purpose of this study was to compare the effects and maintenance of and preference for paired kinesthetic movements (KM) to a traditional drill (TD) procedure on letter–sound correspondence and word recognition with 6 preschool children. In 6 of 11 evaluations, participants mastered the KM set in substantially fewer intervention sessions than the TD set. In 5 of 11 evaluations, participants mastered the KM and TD sets with little differentiation between the number of intervention sessions. No participant mastered the control set. Maintenance data demonstrate a higher number of correct responses for the KM condition across all weeks. Preference varied across participants and was not always consistent with the more effective intervention.     

Assessing object-to-picture and picture-to-object matching as prerequisite skills for pictorial preference assessments

Tangible and pictorial paired-stimulus (PPS) preference assessments were compared for 6 individuals with developmental disabilities. During tangible and PPS assessments, two edible items or photographs were presented on each trial, respectively, and approach responses were recorded. Both assessments yielded similar preference hierarchies for 3 participants who could match pictures and objects but different hierarchies for 3 participants who could not. Reinforcer assessments verified that items identified as high preference on PPS assessments functioned as reinforcers only for participants with matching skills.     

MULTICOMPONENT ASSESSMENT AND TREATMENT OF CIGARETTE PICA

We conducted a multicomponent assessment and treatment for 4 individuals who engaged in cigarette pica. During Phase 1, three stimulus preference assessments were conducted to identify (a) the reinforcing component of the cigarette, (b) potential alternative reinforcers that may be used during treatment, and (c) whether the alternative reinforcer would compete effectively with cigarettes. Results were successful in identifying the reinforcing component of the cigarette and suggested the feasibility of using alternative reinforcers during treatment to eliminate cigarette pica. During Phase 2, the effects of two treatment procedures were evaluated. Noncontingent reinforcement (NCR) with the alternative edible reinforcer reduced the pica of 2 of the participants, but effects were not maintained when the initial dense schedule of NCR was thinned. Subsequently, differential reinforcement of alternative behavior with the alternative edible reinforcer was effective in reducing pica for 3 participants. An evaluation of nine treatment procedures failed to identify an effective intervention for the remaining participant; consequently, preventive measures were designed to minimize occurrences of cigarette pica.     

Reinforcement contingencies and signal detection.

Pigeons were trained to discriminate temporal stimuli in a discrete-trial signal-detection procedure. Pecks to one side key were reinforced intermittently after exposure to one duration, and pecks to the other side key were reinforced intermittently after exposure to a different duration. In Experiment I, the allocation of reinforcers was varied systematically for correct responses and for errors, using a procedure that controlled the obtained numbers of reinforcers. When reinforcers were allocated symmetrically, the level of discrimination decreased as the proportion of reinforcers for errors increased. When reinforcers were allocated asymmetrically, the decrease in discrimination was less systematic. Bias toward one or the other side key roughly matched the ratio of reinforcers obtained by pecks at those keys, independent of the level of discrimination. In Experiment II, the overall rate of reinforcement for correct responses was varied both within and between experimental conditions. The level of discrimination was positively related to the overall rate of reinforcement. The discrimination data of both experiments were interpreted in relation to the contingencies of reinforcement and nonreinforcement, characterized by the average difference in reinforcement probability for correct responses and errors.