Incorporating multiple secondary targets into learning trials for individuals with autism spectrum disorder

The current study examined the outcome of presenting multiple secondary targets in learning trials for individuals with autism spectrum disorder. We compared conditions in which (a) a secondary target was presented in the antecedent and consequence of trials, (b) two secondary targets were presented in the consequence of trials, (c) one secondary target was presented in the consequence of each trial, and (d) no additional targets were presented trials. The participants acquired the majority of secondary targets. Presenting one or multiple secondary targets per trial, regardless of the location of these secondary targets, increased the efficiency of instruction in comparison to a condition with no secondary target.     

Inserting mastered targets during error correction when teaching skills to children with autism

Research has identified a variety of effective approaches for responding to errors during discrete‐trial training. In one commonly used method, the therapist delivers a prompt contingent on the occurrence of an incorrect response and then re‐presents the trial so that the learner has an opportunity to perform the correct response independently. Some authors recommend inserting trials with previously mastered targets between the prompted response and opportunities to respond independently, but no studies have directly examined the benefits of this approach. In this study, we manipulated the placement of trials with mastered targets during discrete‐trial training to compare the effectiveness of error correction with and without this recommended insertion procedure. Four children with autism participated, and each was taught 18 targets across 3 target sets. Results indicated that embedding trials with mastered targets into error correction may not confer benefits for most children and that doing so may lead to less efficient instruction.     

Comparison of progressive prompt delay with and without instructive feedback

We examined the effectiveness and efficiency of 2 instructional arrangements using progressive prompt delay (PPD) with 3 young children with autism and 1 child with developmental delays. Specifically, we compared PPD with instructive feedback (IF) to PPD without IF in an adapted alternating treatment design. The results suggested that (a) children with autism and developmental delays can learn when PPD is used with IF, (b) IF can be an effective method of instruction for young children with autism and developmental delays, and (c) the combination of PPD and IF can increase the efficiency of instruction. Data collected 8 to 9 weeks after instruction ended showed that participants maintained mastery of 58% to 92% of the acquired behaviors. We discuss these results within the constraints and limitations of the data and recommend areas for future research.     

Emergent control for play responses following instructive feedback for children with autism spectrum disorder

Play provides children learning opportunities in the natural environment to acquire communication skills. While working to establish skills that may lead to additional leisure and social opportunities of children with autism spectrum disorder (ASD), procedures need to be both effective and efficient. One way to increase efficiency of teaching is through the use of instructive feedback (IF). Therefore, the purpose of the current study is to systematically replicate and extend previous research by examining if play behaviors emerge when using IF to teach conceptually related primary (i.e., tacts) and secondary targets (i.e., play skills). The results of the present study extend previous research by demonstrating the effectiveness of teaching tacts to individuals with ASD, and that using IF during tact training can help promote the acquisition of play skills.     

Instructive feedback embedded within group instruction for children diagnosed with autism spectrum disorder

The present study evaluated the effects of instructive feedback embedded within a group discrete trial teaching to teach tact relations to nine children diagnosed with autism spectrum disorder using a nonconcurrent multiple‐baseline design. Dependent variables included correct responses for: primary targets (directly taught), secondary targets (taught via instructive feedback), primary observational targets (directly taught to other members of the group), and secondary observational targets (taught via instructive feedback provided to other members of the group). Results showed that all nine participants reached the mastery criterion for the primary targets, as well as acquired the secondary and observational targets without direct teaching. Clinical implications and areas for future research are provided.     

Differential reinforcement with and without instructional fading

We evaluated a differential-reinforcement-based treatment package for the reduction of problem behavior during instructional situations. Differential reinforcement of alternative behavior (DRA; compliance) was implemented across two conditions. During one condition, instructions were presented approximately once every other minute. This condition was considered the terminal goal for treatment. During the second condition, the rate of instructions was gradually increased (beginning at zero and ending when instruction rate was similar to the first condition). Results indicated that DRA with instructional fading resulted in less problem behavior than DRA without instructional fading. These results are similar to previous studies regarding the utility of instructional fading.     

Teaching children with autism spectrum disorder to tact olfactory stimuli

Research on tact acquisition by children with autism spectrum disorder (ASD) has often focused on teaching participants to tact visual stimuli. It is important to evaluate procedures for teaching tacts of nonvisual stimuli (e.g., olfactory, tactile). The purpose of the current study was to extend the literature on secondary target instruction and tact training by evaluating the effects of a discrete‐trial instruction procedure involving (a) echoic prompts, a constant prompt delay, and error correction for primary targets; (b) inclusion of secondary target stimuli in the consequent portion of learning trials; and (c) multiple exemplar training on the acquisition of item tacts of olfactory stimuli, emergence of category tacts of olfactory stimuli, generalization of category tacts, and emergence of category matching, with three children diagnosed with ASD. Results showed that all participants learned the item and category tacts following teaching, participants demonstrated generalization across category tacts, and category matching emerged for all participants.     

The effectiveness of and preschoolers' preferences for variations of multiple-schedule arrangements

Multiple schedules of reinforcement have been used to teach children to recruit attention only when it is available, thereby minimizing disruptive requesting during instructional activities. This procedure involves alternating periods of continuous reinforcement (CRF) with periods of extinction and correlating each period with a distinct and continuous discriminative stimulus. The present study evaluated the effectiveness of and children's preferences for multiple schedules in which (a) two different stimuli, one correlated with reinforcement (S+) and another correlated with extinction (S-), were presented; (b) only an S+ was presented (i.e., no stimulus was correlated with extinction), and (c) neither an S+ nor an S- was presented (i.e., a mixed schedule). S+/S- and S+ arrangements were similarly effective for 7 children, but 3 preferred the S+/S- condition and 4 preferred the S+ condition. Correlational analyses suggested that children who responded more effectively given the S- (discrimination indexes were relatively high) preferred the S+/S- condition, whereas children who responded less effectively given the S- preferred the S+ condition. The implications of these findings for arranging multiple schedules for social responses are discussed.     

Second-order schedules: brief shock at the completion of each component

Pigeons worked on second-order schedules in which completion of fixed-interval component schedules was reinforced with food according to a variable-interval schedule of reinforcement. The completion of each fixed-interval component resulted in the presentation of a brief electric shock. In one condition (shock-paired), the completion of every fixed-interval component, including those that ended in food, resulted in the shock. In another condition (shock-nonpaired), completion resulted in shock except for those components that ended in food. Shock presentations resulted in a positively accelerated rate within fixed-interval components. This patterning within components was similar whether the shock was intermittently paired with food or not. Response rates tended to decrease as shock intensity increased. The characteristic fixed-interval response pattern within components did not occur when shock presentations were omitted at the end of each component (tandem schedule). When shocks were scheduled but food was no longer presented (extinction) response rates declined to a near-zero level. The performance under shock conditions is similar to that in other studies in which visual and auditory stimuli are presented at the completion of component schedules.     

Establishing preference for unreliable reinforcement in adults with dual diagnoses

We evaluated the choice responding of three adults dually diagnosed with developmental and psychiatric disabilities using concurrent schedules of reinforcement. Specifically, participants were given a choice between a response option resulting in reliable reinforcement and a response option resulting in unreliable reinforcement. Our primary purpose was to shift preference from reliable to unreliable reinforcement via the systematic presentation of stimuli during delay intervals. A second purpose was to evaluate the effectiveness of intervening stimuli in shifting preference at differing delay-to-reinforcement intervals. Preference for unreliable reinforcement was first examined in the absence of stimulus presentations during delays, at three different delay values. Next, we aimed to establish preference for unreliable reinforcement by presenting pictures of reinforcers during delays preceding unreliable reinforcement. Preference was again examined at three different delay values. In the absence of stimulus presentations during delays, participants were shown to prefer reliable reinforcement, particularly at the longer delay value. When stimuli were presented during the delays, two of the three participants preferred unreliable reinforcement, particularly the longer the delay value. These results suggest that the presentation of intervening stimuli during delays may help facilitate tolerance for unreliable reinforcement.     

Effects of modeling versus instructions on sensitivity to reinforcement schedules

This study examined the effects of modeling versus instructions on the choices of 3 typically developing children and 3 children with attention deficit hyperactivity disorder (ADHD) whose academic responding showed insensitivity to reinforcement schedules. During baseline, students chose between successively presented pairs of mathematics problems associated with different variable-interval schedules of reinforcement. After responding proved insensitive to the schedules, sessions were preceded by either instructions or modeling, counterbalanced across students in a multiple baseline design across subjects. During the instruction condition, students were told how to distribute responding to earn the most reinforcers. During the modeling condition, students observed the experimenter performing the task while describing her distribution of responding to obtain the most reinforcers. Once responding approximated obtained reinforcement under either condition, the schedules of reinforcement were changed, and neither instruction nor modeling was provided. Both instruction and modeling interventions quickly produced patterns of response allocation that approximated obtained rates of reinforcement, but responding established with modeling was more sensitive to subsequent changes in the reinforcement schedules than responding established with instructions. Results were similar for students with and without ADHD.     

Evaluating discrete trial teaching with instructive feedback delivered in a dyad arrangement via telehealth

Telehealth research in the field of applied behavior analysis (ABA) has focused on the training and supervision of others to implement various behavior analytic procedures. Current guidelines for practicing telehealth suggest that direct telehealth services may be appropriate for some individuals diagnosed with autism spectrum disorder, but more research is needed. This study evaluated the effects of discrete trial teaching with instructive feedback in a dyad arrangement delivered directly via telehealth to teach tact relations to 6 children diagnosed with autism spectrum disorder. All participants and the experimenter were located in different physical locations. All participants learned their primary and secondary targets, and 5 of the participants acquired the observational primary and secondary targets without direct teaching. Areas of future research and clinical implications are discussed in the context of telehealth service delivery.     

Interval reinforcement of choice behavior in discrete trials

Pigeons were trained to peck at red or green keys presented simultaneously in discrete trials. In one experiment, reinforcements were arranged by concurrent variable-interval schedules. The proportion of responses to green approximately matched the proportion of reinforcements produced by pecking green. Detailed analysis of responding revealed a systematic decrease in the probability of switching from green to red within sequences of trials after reinforcement. This trend corresponded to sequential changes in the relative frequency of reinforcement, and not to sequential changes in probability of reinforcement. In a second experiment, reinforcements were scheduled probabilistically every seventh trial. Even though there were no contingencies on pecking during the first six post-reinforcement trials, choices of green on the first response after reinforcement matched the proportion of reinforcements for pecking green. These results extend the generality of overall matching under concurrent reinforcement.     

Effects of continuous and intermittent reinforcement for problem behavior during functional communication training

We evaluated the effectiveness of functional communication training (FCT) in reducing problem behavior and in strengthening alternative behavior when FCT was implemented without extinction. Following the completion of functional analyses in which social-positive reinforcement was identified as the maintaining variable for 5 participants' self-injurious behavior (SIB) and aggression, the participants were first exposed to FCT in which both problem behavior and alternative behavior were reinforced continuously (i.e., on fixed-ratio [FR] 1 schedules). During subsequent FCT conditions, the schedule of reinforcement for problem behavior was made more intermittent (e.g., FR 2, FR 3, FR 5, etc.), whereas alternative behavior was always reinforced according to an FR 1 schedule. Results showed that 1 participant's problem behavior decreased and alternative behavior increased during FCT when both behaviors were reinforced on FR 1 schedules. The remaining 4 participants shifted response allocation from problem to alternative behavior as the schedule of reinforcement for problem behavior became more intermittent. These results suggest that individuals might acquire alternative responses during FCT in spite of inconsistencies in the application of extinction, although even small errors in reinforcement may compromise treatment effects.     

An evaluation of estimation data collection to trial‐by trial data collection during discrete trial teaching

There are many data collection procedures used during discrete trial teaching including first‐trial data collection, probe data, trial‐by‐trial data collection, and estimation data. Continuous, or trial‐by‐trial data collection, consists of the interventionist collecting data on learner behavior on each trial. Estimation data consists of the interventionist estimating learner performance after a teaching session using a rating scale. The purpose of the present study was to compare trial‐by‐trial data collection to estimation data collection during discrete trial teaching to teach children expressive labels. The data collection procedures were examined in terms of accuracy of data collection, efficiency of teaching (i.e., number of trials delivered per session), and rate of child acquisition of targets. Results of the adapted alternating treatment design replicated across three participants and multiple targets found estimation data collection to be as accurate as trial‐by‐trial data collection in determining mastery of targets. Estimation data collected by the interventionist was also found to be accurate when compared to the actual trial‐by‐trial data collected after the study concluded.     

Effects of modeling rote versus varied responses on response variability and skill acquisition during discrete‐trial instruction

Despite its advantages, discrete‐trial instruction (DTI) has been criticized for producing rote responding. Although there is little research supporting this claim, if true, this may be problematic given the propensity of children with autism to engage in restricted and repetitive behavior. One feature that is common in DTI that may contribute to rote responding is the prompting and reinforcement of one correct response per discriminative stimulus. To evaluate the potential negative effects of rote prompts on varied responding, we compared the effects of modeling rote versus varied target responses during the teaching of intraverbal categorization. We also evaluated the effects of these procedures on the efficiency of acquisition of any one correct response. For all four children, any increase in varied responding was fleeting, and for two participants, acquisition was slower in the variable‐modeling condition.     

Fixed-interval responding under second-order schedules of food presentation or cocaine injection.

Squirrel monkeys operated a key under second-order schedules in which every tenth completion of a 5-minute fixed interval resulted in either presentation of food or intravenous injection of cocaine. When a 2-second light was presented at the completion of the component fixed-interval schedules, positively accelerated responding developed and was maintained in each component. Over a tenfold range of doses of cocaine(30 to 300 microgram/kg/injection) and amounts of food (0.75 to 7.5 g/presentation); the second-order schedule of cocaine injection maintained higher average rates of responding than the second-order schedule of food presentation. Substituting saline for cocaine or eliminating food presentation decreased average rates of responding. When no stimulus change occurred at the completion of the first nine component fixed-interval schedules, but the 2-second light and food presentation or cocaine injection still occurred after the tenth component, only low and relatively constant rates of responding were maintained in each component. Patterns of responding characteristic of 5-minute fixed-interval schedules were maintained by the 2-second light paired with either cocaine injection or food presentation, though the maximum frequency of cocaine injection or food presentation was less than once per 50 minutes.     

Conditioned reinforcement and discrimination performance

Pigeons were trained in a three-key chamber to peck one side key in the presence of a vertical line on the center key and to peck the other side key in the presence of a horizontal line. Correct choice responses were reinforced with food according to fixed- and variable-ratio, fixed-interval, and differential-reinforcement-of-long-latency schedules of reinforcement. For each schedule, the birds performed under each of two conditions: (1) each correct choice response produced a brief presentation of stimuli intermittently paired with food, then the next trial; (2) each correct choice response produced an intertrial interval only. For all schedules except one long latency schedule, response rates were higher under the condition of brief stimulus presentation than under the comparable control condition. Presentation of brief magazine stimuli increased choice accuracy. The amount of change in accuracy was correlated with the rate of food presentation. Performance under the schedules with highest food reinforcement rates showed no enhancement; performance under the schedules with the lowest reinforcement rates showed the greatest enhancement.     

Memory benefits during visual search depend on difficulty

In three experiments we explored whether memory for previous locations of search items influences search efficiency more as the difficulty of exhaustive search increases. Difficulty was manipulated by varying item eccentricity and item similarity (discriminability). Participants searched through items placed at three levels of eccentricity. The search displays were either identical on every trial (repeated condition) or the items were randomly reorganised from trial to trial (random condition), and search items were either relatively easy or difficult to discriminate from each other. Search was both faster and more efficient (i.e., search slopes were shallower) in the repeated condition than in the random condition. More importantly, this advantage for repeated displays was greater (1) for items that were more difficult to discriminate and (2) for eccentric targets when items were easily discriminable. Thus, increasing target eccentricity and reducing item discriminability both increase the influence of memory during search.