Instructions as discriminative stimuli

Four undergraduates were exposed to a fixed-ratio schedule under an instruction to respond slowly and to a differential-reinforcement-of-low-rate 5-s schedule under an instruction to respond rapidly. Following this, a fixed-interval schedule was in effect under those same two sets of instructions. For 3 of 4 subjects, response rates were higher with the instruction to respond slowly than with the instruction to respond rapidly during the fixed-interval schedule. For the remaining subject, low-rate responding with the instruction to respond rapidly continued during the first 17 reinforcements of the fixed-interval schedule. Such control by instructions was not observed for other subjects exposed only to a fixed-interval schedule, with or without instructions. The results demonstrate that the effect of instructions can be altered by contingencies and suggest that instructions can function as discriminative stimuli.     

The Rapid Establishment of Low-Rate Fixed Interval Responding by Humans in a Single Experimental Session

Subjects responding to receive monetary reinforcement on a fixed interval schedule were read instructions containing varying amounts of information regarding the schedule contingencies prior to their participation in the experiment. In addition, some subjects were exposed to an additional response cost contingency for early responding. The results indicate that reliable low-rate fixed interval responding can be rapidly generated in a single 45-minute experimental session when subjects are provided with explicit instructions together with the response cost contingency.

     

Contingency-shaped and rule-governed behavior: instructional control of human loss avoidance

Instructions can override the influence of programmed schedules of reinforcement. Although this finding has been interpreted as a limitation of reinforcement schedule control in humans, an alternative approach considers instructional control, itself, as a phenomenon determined by subjects' reinforcement histories. This approach was supported in a series of experiments that studied instructional and schedule control when instructions either did or did not accord with the schedule of reinforcement. Experiment I demonstrated that accurate instructions control discriminative performances on multiple avoidance schedules, and that such control persists in a novel discrimination. Experiments II and III showed that elimination of instruction-following occurs when inaccurate instructions cause subjects to contact a monetary loss contingency. Experiment IV demonstrated the reinforcing properties of accurate instructions. Skinner's view of rule-governed behavior is consistent with these findings, and can be extended to account for many aspects of instructional control of human operant behavior.     

Effects of reinforcement and response-cost history on instructional control

The present study compared the effects of reinforcement or punishment versus no additional consequences for instruction following on instructional control and subsequent rule-governed insensitivity. In two experiments, adult participants were presented with repeated choices between a short progressive-time schedule and either a fixed time-schedule or a longer progressive-time schedule. In Experiment 1, three groups were given an initially accurate instruction relative to the direct contingency. A control group experienced no additional consequences for compliance with instructions, whereas compliance resulted in additional points for a second group, and noncompliance led to the subtraction of points for a third group. In a subsequent phase, instructions became inaccurate and there were no additional consequences for compliance or noncompliance for any group. Consistent with previous results, rule-governed insensitivity was observed in all participants. Experiment 2 employed the same procedure, except instructions were inaccurate throughout all sessions, and compliance in the subsequent phase resulted in diminishing points per session. Reinforcement for following instructions increased instructional control and subsequent rule-governed insensitivity. This increase was maintained even after the termination of additional consequences, a result that supports theoretical suggestions that a history of reinforcement for complying with instructions and rules is an important factor in rule-governed insensitivity.     

Interaction of procedural factors in human performance on yoked schedules

The differential effects of reinforcement contingencies and contextual variables on human performance were investigated in two experiments. In Experiment 1, adult human subjects operated a joystick in a video game in which the destruction of targets was arranged according to a yoked variable-ratio variable-interval schedule of reinforcement. Three variables were examined across 12 conditions: verbal instructions, shaping, and the use of a consummatory response following reinforcement (i.e., depositing a coin into a bank). Behavior was most responsive to the reinforcement contingencies when the consummatory response was available, responding was established by shaping, and subjects received minimal verbal instructions about their task. The responsiveness of variable-interval subjects' behavior varied more than that of variable-ratio subjects when these contextual factors were altered. Experiment 2 examined resistance to instructional control under the same yoked-schedules design. Conditions varied in terms of the validity of instructions. Performance on variable-ratio schedules was more resistant to instructional control than that on variable-interval schedules.     

Effects of Attribution and Schedules of Reinforcement on Performance

Abstract

We examined the impact of attributional instructions and schedules of reinforcement on performance. Attributional instructions were designed to lead to an internal or an external attribution, whereas schedules of reinforcement were either variable ratio or variable interval. Results obtained from 31 American students indicated that the subjects given external attributional instructions made a greater number of responses but did not respond more correctly. The schedule of reinforcement did not influence either the number of responses or the correctness of responses.     

The effects of fixed‐interval schedules on variability of pigeons' pecking location

Many studies that have investigated performance under reinforcement schedules have measured response rate or interresponse time, which reflect the temporal dimension of responding; however, relatively few studies have examined other dimensions. The present study investigated the effects of fixed‐interval schedules on the location of pigeons' pecking response. A circular response area 22.4 cm in diameter was used so that the pecking responses were effective over a wide range. Pigeons were exposed to a fixed‐interval schedule whose requirement was systematically varied between conditions. Response location moved closer to the location of the last reinforced response as time elapsed in each trial. Additionally, as the fixed‐interval duration requirement increased, response locations shifted to the border of the response area and the variability of response locations increased. These results suggest that fixed‐interval schedules systematically control response location.     

Human, free-operant avoidance of “time out” from monetary reinforcement

To assess the aversive effects of withdrawing monetary reinforcement, human subjects were exposed to a free-operant avoidance procedure in which periods of no reinforcement occurred if the subject failed to respond, and each response postponed withdrawal of reinforcement. Avoidance behavior was developed either through specific instructions about the consequence of responding or through preliminary escape-avoidance training. In all cases, rates of response were found to be a positively accelerated function of decreases in the duration by which responding postponed reinforcement withdrawal. The findings with respect to the function relating avoidance behavior to the interval of postponement were viewed as similar to those obtained when shock is used as the aversive event in free-operant avoidance conditioning.     

Sensitivity and Strength: Effects Of Instructions on Resistance to Change

Several research laboratories have found that instructed behavior can be less sensitive to changes in contingencies than shaped behavior. The current experiment examined whether these differences in sensitivity could be related to resistance to change. Two groups of subjects, who were matched on the basis of an initial disruption assessment, were exposed to a variable-interval 30-s schedule of reinforcement with and without a disrupter. The disrupter was a video presentation of a popular television situation comedy. One group received minimal instructions (MI) that told them only that they could earn points exchangeable for money. Each member of the second group received a complete instruction (CI) that described the topography of the target response that was yoked to a MI subject’s stable baseline response rate. The response rates under the disruption condition for the CI subjects were more resistant to change than the MI subjects in 14 out of 15 disruption sessions. These findings are discussed in terms of resistance to change being increased by instructional conditions like those manipulated and that the procedures used to test disruption provide an additional method to !waluate differences between instructed and contingency-governed behavior.

     

Effects of instructional constraints on human fixed-interval performance

Several groups of human subjects were exposed to a variety of experimental conditions involving a fixed-interval 27-second schedule of reinforcement in compound with instructions to constrain in the number of responses within the interreinforcement interval and/or the duration of the experimental session. One group was further exposed to a contingency involving the placement of responses within the IRI. A diversity of patterns of performance was observed, including those typically associated with animal subjects exposed to FI schedules. Generally, the imposition of instructions to minimize session duration reduced post-reinforcement pausing and increased overall reinforcement density from those levels obtained with only instructions to expend a given number of responses per reinforcer. The results are seen to underscore the sensitivity of human fixed-interval performance and the contribution of extra-experimental contingencies.     

Effects of response independent delivery of preferred items and the high‐probability instructional sequence on compliance

The use of the high‐probability (high‐p) instructional sequence to increase compliance, which includes issuing a series of instructions with which a participant is likely to comply immediately before issuing a low‐probability instruction, has received mixed support in the literature. Previous research has suggested that the delivery of response independent reinforcement may be as effective to increase compliance, at least for some types of instructions. In this study, we examined the effects of response independent reinforcement and the high‐p sequence on compliance with two types of instructions with two young children. Results show that neither procedure was effective for increasing compliance for either type of instruction; however, contingent access to a high preference item increased compliance. Results are discussed in terms of the conditions under which response independent delivery of high‐preference items and the high‐p instructional sequence might be effective to increase compliance.     

STIMULUS (INSTRUCTIONAL) FADING DURING EXTINCTION OF SELF-INJURIOUS ESCAPE BEHAVIOR

Three individuals with developmental disabilities were exposed to a series of assessment conditions to identify the source of reinforcement for their self-injurious behavior. In each case, self-injury occurred most often in instructional (demand) situations containing a brief time-out from the task contingent on self-injury, indicating that the behavior was an escape response (i.e., maintained by negative reinforcement). Treatment was implemented in a multiple baseline across subjects design and consisted of extinction (prevention of escape) plus instructional fading (initial elimination of instructions followed by their gradual reintroduction). Results showed that the combined treatment produced immediate and large reductions in self-injury that were maintained as the frequency of instructions was increased across sessions to match the original baseline rate of presentation. Results of a component analysis conducted with 1 subject suggested that stimulus fading accelerated the behavior-reducing effects of extinction.     

Competitive fixed-interval performance in humans

Two persons responded in the same session in separate cubicles, but under a single schedule of reinforcement. Each time reinforcement was programmed, only the first response to occur, that is, the response of only one of the subjects, was reinforced. “Competitive” behavior that developed under these conditions was examined in three experiments. In Experiment 1 subjects responded under fixed-interval (FI) 30-s, 60-s, and 90-s schedules of reinforcement. Under the competition condition, relative to baseline conditions, the response rates were higher and the pattern was “break-and-run.” In Experiment 2, subjects were exposed first to a conventional FI schedule and then to an FI competition schedule. Next, they were trained to respond under either a differential-reinforcement-of-low-rate (DRL) or fixed-ratio (FR) schedule, and finally, the initial FI competition condition was reinstated. In this second exposure to the FI competition procedure, DRL subjects responded at lower rates than were emitted during the initial exposure to that condition and FR subjects responded at higher rates. For all subjects, however, responding gradually returned to the break-and-run pattern that had occurred during the first FI competition condition. Experiment 3 assessed potential variables contributing to the effects of the competitive FI contingencies during Experiments 1 and 2. Subjects were exposed to FI schedules where (a) probability of reinforcement at completion of each fixed interval was varied, or (b) a limited hold was in effect for reinforcement. Only under the limited hold was responding similar to that observed in previous experiments.     

Attention in the pigeon: a reevaluation

During training sessions, pigeons were successively exposed to compounds consisting of a white triangle on a red background and a white circle on a green background. Key pecking intermittently produced grain reinforcers in the presence of one form-color compound. Once key pecking was confined to the compound associated with reinforcement, the elements—red, green, triangle, and circle—were presented during a test in which no reinforcement was available. Each bird pecked nearly exclusively in the presence of the color previously associated with reinforcement, a result that might be interpreted as indicating that the subjects had attended to color, but not form during training. Pecking was next reinforced when either the triangle or the circle was present. Pecking in the presence of the form previously associated with reinforcement was acquired more rapidly. This result suggests that the birds had learned about the forms during training, and that conclusions about attention based on the lack of differential pecking in the nonreinforcement test may not be appropriate.     

Instruction-following behavior of a retarded child and its controlling stimuli

A combination of positive reinforcement and fading of physical guidance was used to teach a profoundly retarded boy specific responses to specific verbal instructions. The design consisted of a multiple baseline of probe data across different verbal instructions. The subject started responding correctly to each verbal instruction as that item was trained in a multiple-baseline order. Generalization did not occur to items that had not yet been trained, nor did it occur to items included to assess generalization. Probes of variations in the verbal instructions, conducted after training was completed, revealed that generalization was minimal except in those cases where the variation consisted of the verb only, the noun only, the noun plus preposition, or where the verb of the instruction was presented last. Training a profoundly retarded 11-yr-old subject to respond to specific verbal instructions did not adequately facilitate the development of a generative instruction-following capability, nor did all verbal elements of the instruction control a specific response.     

Instructions, multiple schedules, and extinction: Distinguishing rule-governed from schedule-controlled behavior

Schedule sensitivity has usually been examined either through a multiple schedule or through changes in schedules after steady-state responding has been established. This study compared the effects of these two procedures when various instructions were given. Fifty-five college students responded in two 32-min sessions under a multiple fixed-ratio 18/differential-reinforcement-of-low-rate 6-s schedule, followed by one session of extinction. Some subjects received no instructions regarding the appropriate rates of responding, whereas others received instructions to respond slowly, rapidly, or both. Relative to the schedule in operation, the instructions were minimal, partially inaccurate, or accurate. When there was little schedule sensitivity in the multiple schedule, there was little in extinction. When apparently schedule-sensitive responding occurred in the multiple schedule, however, sensitivity in extinction occurred only if differential responding in the multiple schedule could not be due to rules supplied by the experimenter. This evidence shows that rule-governed behavior that occurs in the form of schedule-sensitive behavior may not in fact become schedule-sensitive even though it makes contact with the scheduled reinforcers.     

TEACHING SELF‐CONTROL WITH QUALITATIVELY DIFFERENT REINFORCERS

This study examined the effectiveness of using qualitatively different reinforcers to teach self‐control to an adolescent boy who had been diagnosed with an intellectual disability. First, he was instructed to engage in an activity without programmed reinforcement. Next, he was instructed to engage in the activity under a two‐choice fixed‐duration schedule of reinforcement. Finally, he was exposed to self‐control training, during which the delay to a more preferred reinforcer was initially short and then increased incrementally relative to the delay to a less preferred reinforcer. Self‐control training effectively increased time on task to earn the delayed reinforcer.     

A comparison of signaled and unsignaled delay of reinforcement

Pigeons were trained on either a variable-interval 60-second schedule, or on a schedule that differentially reinforced responses that were spaced at least 20 seconds apart. The birds were then exposed to several durations of reinforcement delay, with comparisons between signaled and unsignaled delays. Although unsignaled delays of 5 and 10 seconds produced large decreases in response rate, signaled delays of up to 10 seconds produced only moderate decreases in response rates. In addition, some subjects responded more rapidly with a .5 or 1.0 second duration of unsignaled delay than with immediate reinforcement. These response rate changes occurred regardless of whether the rate of reinforcement concomitantly decreased or increased.     

A multi‐component approach to the treatment of chronic rumination

A multi‐component intervention was used to treat chronic rumination exhibited by an adult female diagnosed with a developmental disability. The intervention consisted of: (a) interruption of precursor behavior, (b) the alternation of 10‐min periods of continued instruction that involved walking and working with (c) 10‐min periods in which instructions were not delivered but a variable time 5‐s schedule of noncontingent attention was programmed, and (d) a 1‐min differential reinforcement of other behavior (DRO) schedule. During the intervention, rumination decreased by 82% relative to baseline. Next, components of the multi‐component intervention were systematically removed to evaluate their individual contribution. Results suggested that each individual component contributed to the overall treatment effects. Copyright © 2010 John Wiley & Sons, Ltd.     

Repeated,within‐session resurgence

Resurgence is a reliable, transient effect that only occasionally is replicated more than once within a single experiment or subject. In the present experiments, within‐session resurgence was generated repeatedly by dividing individual sessions into three phases (Training, Alternative‐Reinforcement, and Resurgence‐Test). In Experiments 1 and 2, resurgence reliably occurred in most of the 22‐30 daily sessions when responding was reinforced on, respectively, fixed‐ and variable‐interval schedules. Resurgence magnitude and duration did decrease across replications for some subjects, but not for others. To examine the utility of the procedure in studying the effects of an independent variable on resurgence, in Experiment 3 the effects of rich and lean baseline and alternative reinforcement rates on resurgence were compared. The target response was eliminated more rapidly, resurgence occurred more often, and usually was greater following rich alternative reinforcement rates. Resurgence was of greater magnitude when the baseline reinforcement rate was relatively lean compared to the alternative reinforcement rate. These experiments provide a reliable method for generating resurgence within individual sessions, instead of across multiple‐session conditions, that can be repeated over many successive sessions.