Response-independent Schedule Research Articles

Evaluation of an automated response-independent schedule on the behavioral welfare of shelter dogs.

Response-independent schedules involve the delivery of an item independent of a response requirement. Often described in the applied behavior analytic literature as "noncontingent reinforcement," they have also frequently been used to reduce undesired or problematic behaviors. The current study examined the use of an automated response-independent food schedule on the behaviors and sound levels of shelter dogs. Several dogs were included in a 6-week reversal design, where a fixed-time 1 min schedule was compared with a baseline condition. Eleven behaviors were measured, as were two areas of each kennel and the overall and session sound intensity (dB) that occurred during the study. The results demonstrated that the fixed-time schedule increased overall activity while decreasing inactivity and led to a reduction in the overall sound intensity measured. Session and hour-to-hour sound-intensity data were less clear, suggesting a potential contextual conditioning effect as well as a need for adjusted methods to study shelter sound. The above are discussed in terms of their potential welfare benefits for shelter dogs as well as the translational approach that this and similar research could contribute to the application and functional understanding of response-independent schedules.

Bridging the gap between laboratory and applied research on response-independent schedules.

In 1948, Skinner described the behavior of pigeons under response-independent schedules as "superstitious," and proposed that the responses were reinforced by contiguous, adventitious food deliveries. Subsequently, response-independent schedules have been of interest to both basic and applied researchers, first to understand the mechanisms involved, and later, as "noncontingent reinforcement" (NCR) to reduce undesirable behavior. However, the potential superstitious effects produced by these schedules have been challenged, with some researchers arguing that antecedent variables play a significant role. This paper examines the evidence for adventitious reinforcement from both laboratory and applied research, the results of which suggest that antecedent, nonoperant functions may be important in fully understanding the effects of NCR. We propose an applied-basic research synthesis, in which attention to potential nonoperant functions could provide a more complete understanding of response-independent schedules. We conclude with a summary of the applied implications of the nonoperant functions of NCR schedules.

Training Petting Zoo Sheep to Act Like Petting Zoo Sheep: An Empirical Evaluation of Response-Independent Schedules and Shaping with Negative Reinforcement.

Simple SummaryThe present study examines the use of response-independent food schedules (food delivered independent of what an animal is doing) and negative reinforcement in the form of a trainer removing themselves from the presence of an animal to effectively train approach and contact behaviors in petting zoo sheep. All sheep had previously been reported to avoid/escape the presence of zoo staff and caretakers, as well as refuse to eat in the presence of any persons. In Experiment 1, we were able to effectively use response-independent schedules to produce both approach and contact behaviors in a Hampshire sheep. In Experiment 2, a Jacob sheep was trained for approach/contact via a shaping procedure that initially rewarded approach behaviors by removing the presence of the trainer (negative reinforcement), and was later switched to rewarding responses directly with food (positive reinforcement) once the sheep began to regularly eat in the trainer’s presence. The results are discussed with respect to how both procedures are effective in examining the applied approach/avoidance behaviors with zoo animals, as well as the greater ethical considerations involved in using negative vs. positive reinforcement to train animals.Shaping through differential reinforcement of successive approximations to a target response has been a cornerstone procedure for the training of novel behavior. However, much of how it has traditionally been implemented occurs through informal observation, rather than any direct, systematic measurement. In the present study, we examine the use of response-independent food schedules and shaping for increasing approach and contact behaviors in petting zoo sheep. In Experiment 1, a fixed-time (FT) 15 s food schedule was used to effectively increase approach and contact behaviors in one sheep. In Experiment 2, negative reinforcement in the form of removal of the presence of a trainer was made contingent on the successful completion of approximations within a shaping procedure and later switched to food rewards. A changing-criterion design was used to empirically examine the effects of the shaping procedure during each step of the program. The result is one of the first studies to demonstrate the utility of using negative reinforcement within a shaping procedure to successfully intervene on approach/avoidance behaviors in an applied animal setting.

Temporal distributions of schedule-induced licks, magazine entries, and lever presses on fixed- and variable-time schedules.

In this article, schedule-induced drinking (SID) refers to increased drinking by hungry rats exposed to intermittent delivery of food pellets. Two major accounts of SID differ in their explanation of why such drinking tends be concentrated soon after pellet delivery. Temporal discrimination theories propose that drinking is a form of displacement activity that occurs when a pellet is least likely. Adventitious reinforcement theories propose that drinking is displaced to early in an interpellet interval (IPI) by magazine-directed behavior that occurs toward the end of an IPI. The main aim of this study was to examine the latter response-competition account by recording distributions of both licking and magazine entries as SID developed when pellets were delivered to different groups either on a fixed-time (FT 30 s) or on a variable-time schedule (VT 30 s), as in Experiment 1. Although VT 30-s schedules produced essentially flat distributions of magazine entries, licking still tended to be concentrated early in an IPI. Furthermore, there was no indication (Experiments 1 and 2) that magazine entry distributions developed ahead of licking distributions. Experiment 3 examined distributions of lever presses instead of licks: Initially high rates of lever pressing declined both with response-independent schedules (FT and VT) and when a minimal response-dependency was introduced (recycling conjunctive schedule), yet this response also tended to be most frequent soon after pellet delivery. Overall, the data were generally consistent with temporal conditioning theories.

Religion as schedule-induced behavior.

In this article, I argue that a class of religious behaviors exists that is induced, for prepared organisms, by specific stimuli that are experienced according to a response-independent schedule. Like other schedule-induced behaviors, the members of this class serve as minimal units out of which functional behavior may arise. In this way, there exist two classes of religious behavior: nonoperant schedule-induced behaviors and operant behaviors. This dichotomy is consistent with the distinction insisted upon by religious scholars and philosophers between "graceful" and "effortful" religious behaviors. Embracing the distinction allows an explanation of many aspects of religious experience and behavior that have been overlooked or disregarded by other scientific approaches to religion.

AVOIDANCE OF TIMEOUT FROM RESPONSE‐INDEPENDENT FOOD: EFFECTS OF DELIVERY RATE AND QUALITY

In three experiments, a rat's lever presses could postpone timeouts from food pellets delivered on response-independent schedules. In Experiment 1, the pellets were delivered at variable-time (VT) rates ranging from VT 0.5 to VT 8 min. Experiment 2 replicated the VT 1 min and VT 8 min conditions of Experiment 1 with new subjects. Finally, subjects in Experiment 3 could postpone timeouts from delivery of pellets that differed in quality rather than quantity (unsweetened versus sweetened pellets). In general, response rates and success in avoiding increased as a function of the rate and quality of the pellets. Also, performance efficiency increased as the experiments progressed, that is, the avoidance response occurred later and later in the response-timeout interval. The results support the conclusion that timeout from reinforcement has functional properties similar to those of more commonly studied aversive stimuli (e.g., shock).

INDUCED ATTACK DURING FIXED‐RATIO AND MATCHED‐TIME SCHEDULES OF FOOD PRESENTATION

Adjunctive or induced behavior is generated during a variety of schedules of reinforcement. Several theoretical conceptualizations suggest that rate of reinforcement is the primary variable controlling the strength or levels of induced behavior. The operant response requirement within the schedule context has not been extensively studied as a determinant of induced responding. In the present study, levels of induced attack by food-deprived pigeons against restrained conspecifics were compared during response-dependent and response-independent schedules of food presentation equated or yoked interval-by-interval for reinforcement frequency. Experiment 1 compared levels of attack induced by fixed-ratio schedules of key pecking and yoked "matched-time" schedules. Experiment 2 similarly compared chained fixed-ratio 1 fixed-ratio 74 and yoked chained matched-time matched-time schedules. In both experiments, the response-dependent schedules generated greater levels (amount and probability) of induced attack than the response-independent time-based schedules. Thus, the ratio response requirement may be an important determinant of levels of induced responding, and the lower levels of attack observed during the response-independent condition may not be due to the absence of stimuli predicting food presentations. It is concluded that rate of reinforcement is not the sole variable determining levels of induced responding and that response-based and time-based schedules differ in their generation of induced responding.

EFFECTS OF NONCONTINGENT REINFORCEMENT ON PROBLEM BEHAVIOR AND STIMULUS ENGAGEMENT: THE ROLE OF SATIATION, EXTINCTION, AND ALTERNATIVE REINFORCEMENT

This study examined the effects of noncontingent reinforcement (NCR) with and without extinction on problem behavior and stimulus engagement (consumption of reinforcement) of 4 participants. Reductions in problem behavior using NCR have frequently been attributed to both satiation of the reinforcer and extinction. In the current study, aspects of the NCR treatment effects were difficult to explain based solely on either a satiation or an extinction account. Specifically, it was found that stimulus engagement remained high throughout the NCR treatment analysis, and that problem behavior was reduced to near-zero levels during NCR without extinction. The implications of these findings are discussed with respect to the satiation and extinction hypotheses frequently described in the applied literature. Findings from basic studies examining the effects of response-independent schedules are presented, and are used as the basis for a matching theory account of NCR-related effects. It is proposed that reductions in problem behavior observed during NCR interventions may be a function of the availability of alternative sources of reinforcement.

Contingencies of Superstition: Self-Generated Rules and Responding During Second-Order Response-Independent Schedules

Nacogdoches Independent School District Experimental conditions explored the development of fallacious rules and assessed the rates and durations of superstitious responding by children under the influence of standard and second-order response-independent reinforcement. During the presentation of computer-generated math problems, subjects in Experiment 1 had access to a computer and keyboard. Group 1 received second-order, random-time (RT) reinforcement by way of a coin toss graphic procedure (mean reinforcement rate of 1/min). This procedure rendered an effect analogous to a "slot-machine" and matching icons produced monetary re inforcement displayed on the computer screen. A second group obtained response-independent reinforcement according to a standard random-time (RT) 30-s schedule (mean reinforcement rate of 2/min). A control group received no scheduled consequences but was exposed to the same demand conditions. After 10 min , students in all groups answered questions regarding "why" they had performed problems. Subsequently, experimental subjects were exposed to the same conditions for 10 min after which reinforcement was terminated; however, a series of problems remained available for solving. Over the course of the experiment, and particularly during extinction, Group 1 subjects performed at higher rates and longer durations. Experiment 2 replicated Experiment 1, but it examined the effects of second-order response-independent reinforcement on fixed-time (FT) schedules. Students who had been exposed to second-order response-independent reinforcement demonstrated higher rates and longer durations of problem solving. Outcomes suggest that, -independent of FT or RT schedules, second-order response-independent contingencies appear to generate elaborate fallacious rules and particularly long durations of superstitious responding.

TURNING BACK THE CLOCK ON SERIAL‐STIMULUS SIGN TRACKING

Two experiments examined the effects of a negative (setback) response contingency on key pecking engendered by a changing light-intensity stimulus clock (ramp stimulus) signaling fixed-time 30-s food deliveries. The response contingency specified that responses would immediately decrease the light-intensity value, and, because food was delivered only after the highest intensity value was presented, would delay food delivery by 1 s for each response. The first experiment examined the acquisition and maintenance of responding for a group trained with the contingency in effect and for a group trained on a response-independent schedule with the ramp stimulus prior to introduction of the contingency. The first group acquired low rates of key pecking, and, after considerable exposure to the contingency, those rates were reduced to low levels. The rates of responding for the second group were reduced very rapidly (within four to five trials) after introduction of the setback contingency. For both groups, rates of responding increased for all but 1 bird when the contingency was removed. A second experiment compared the separate effects of each part of the response contingency. One group was exposed only to the stimulus setback (stimulus only), and a second group was exposed only to the delay of the reinforcer (delay only). The stimulus-only group's rates of responding were immediately reduced to moderate levels, but for most of the birds, these rates recovered quickly when the contingency was removed. The delay-only groups's rates decreased after several trials, to very low levels, and recovery of responding took several sessions once the contingency was removed. The results suggest that (a) sign-tracking behavior elicited by an added clock stimulus may be reduced rapidly and persistently when a setback contingency is imposed, and (b) the success of the contingency is due both to response-dependent stimulus change and response-dependent alterations in the frequency of food delivery. The operation of the contingency is compared with the effects of secondary reinforcement and punishment procedures.

Discriminative Versus Reinforcing Properties of Schedules as Determinants of Schedule Insensitivity in Humans

Compliance with instructions to respond on response-independent schedules was studied to see if schedule insensitivity is determined by reinforcement of inappropriate responding or if discriminative features of schedules support inappropriate instructional control. College students were asked to prevent unpreventable mixed random-, mixed fixed-, or fixed-time tones by pressing left and right panels and, during interspersed timeout periods, to guess about how to prevent tones. Subjects responding on mixed schedules produced the highest rates and were likely to report that they prevented tones. Fixed-time subjects pressed at the lowest rates and never reported that tones were preventable. Schedule-insensitive compliance under mixed schedules was not reinforced by response-independent stimuli; instead, compliance was occasioned by fluctuations in stimuli that gave the appearance of a contingency, and fixed-time subjects discriminated that responses were ineffective. This suggests that events with discriminative properties that are compatible with instructed behavior occasion compliance, whereas those with incompatible properties do not.

Comparative effects of food and water deprivation on movement patterns in the pigeon (Columba Livia)

Groups of naive pigeons were either food or water deprived and exposed to response-independent fixed time schedules of reinforcement. Reinforcers were always appropriate to the deprivation state. After 15 Phase One sessions under the original deprivation state, an additional 15 Phase Two sessions were run under the alternate deprivation regimen. The Phase One results indicated that the frequency of movement over time, as measured by floorboard panels, had a characteristic distribution depending on deprivation state. After state-switch in Phase Two, both groups exhibited changes in frequency distribution over time, but the new distributions were different from those produced in subjects without any deprivation history. There appeared to be sustained effects on movement patterns due to prior exposure to alternate deprivation and periodic feeding regiments, results which confirm earlier experimental work. The findings are discussed in light of research on the effect of prior response-independent schedule training, the matching law, and the effects of contextual conditioning.

Anticipatory drinking in rats: Compensatory adjustments in the local rate of intake

The current experiment examined whether dehydrated rats could learn to anticipate disruption of access to water. Previous research showed that rats running in a wheel in order to drink compensated for local disruptions on intake by increasing their rate of intake after, but not prior to the initial disruption. The present experiment exposed rats to either a fixed-ratio (FR) schedule that required rats to run in order to drink or a matched, fixed-time (FT) schedule that allowed the animals intermittent access to water without running. Access to water was disrupted by restricting the quantity of water available per drink bout. Rats increased their local rate of water intake prior to the disruption under the FT schedule but not under the FR schedule. The results suggest that rats can learn to increase their local rate of intake in anticipation of local restrictions on water under response-independent (FT) schedules. It was hypothesized that these anticipatory increases in the local rate of intake resulted from a priming effect due to the motivating effects of stimuli associated with water and/or frustration resulting from attempts to drink prior to water availability.

SUPERSTITIOUS BEHAVIOR IN HUMANS

Twenty undergraduate students were exposed to single response-independent schedules of reinforcer presentation, fixed-time or variable-time, each with values of 30 and 60 s. The reinforcer was a point on a counter accompanied by a red lamp and a brief buzzer. Three color signals were presented, without consistent relation to reinforcer or to the subjects' behavior. Three large levers were available, but the subjects were not asked to perform any particular behavior. Three of the 20 subjects developed persistent superstitious behavior. One engaged in a pattern of lever-pulling responses that consisted of long pulls after a few short pulls; the second touched many things in the experimental booth; the third showed biased responding called sensory superstition. However, most subjects did not show consistent superstitious behavior. Reinforcers can operate effectively on human behavior even in the absence of a response-reinforcer contingency and can, in some cases, shape stable superstitious patterns. However, superstitious behavior is not a consistent outcome of exposure of human subjects to response-independent reinforcer deliveries.

PREFERENCE FOR LESS SEGMENTED FIXED‐TIME COMPONENTS IN CONCURRENT‐CHAIN SCHEDULES OF REINFORCEMENT

A concurrent-chain procedure was used to examine choice between segmented and less segmented response-independent schedules of reinforcement. A pair of independent, concurrent variable-interval 60-s schedules were presented in the initial link, along with a 1.5-s changeover delay. A chained fixed-interval fixed-time and its corresponding tandem schedule constituted the terminal links. The length of the fixed-interval schedule in the terminal link was varied between 5 s and 30 s while that of the fixed-time schedule was kept at 5 s over conditions. The first components of both terminal-link schedules were accompanied by the same stimulus. Except in the baseline condition, the onset of the second component of the terminal-link chained schedule was accompanied by either a localized (key color) or a nonlocalized (dark houselight) stimulus change. Stimulus conditions were constant during the terminal-link tandem schedule. With three exceptions, pigeons demonstrated a slight preference for the tandem over the chained schedule in the terminal link. Furthermore, this preference varied inversely with the length of the first component. In general, these results are consistent with previous studies that reported an adverse effect on choice by segmenting an interval schedule into two or more components, but they are inconsistent with studies that reported preference for signaled over unsignaled delay of reinforcement.

Infant visual attention under response-contingent and response-independent conditions

The visual attention behavior of 2- to 3-month-old infants was monitored as part of their participation in an operant conditioning study. Attention was monitored under three conditions: a baseline condition where a visual target remained stationary; a baseline conditioning where the target was made to move on an aperiodic, response-independent schedule; and a conditioning phase where the target was operantly under the control of the subjects. Fixation time differed significantly as a function of experimental condition, with the response-contingent condition producing the greatest amount of fixation and the stabile, baseline condition producing the least amount of fixation. The implications of the findings for intervention purposes are discussed.

Factors affecting schedule-induced wood-chewing in rats: Percentage and rate of reinforcement, and operant requirement

In Experiment 1, rats were allowed to acquire either schedule-induced drinking or schedule-induced wood-chewing behavior under a fixed-interval (FI) 60-sec schedule of food reinforcement, following which food was omitted from 20% and then 50% of interreinforcement intervals. Omission of food severely disrupted induced drinking but had relatively little effect on induced wood-chewing. Experiment 2 investigated wood-chewing as a function of reinforcement rate, using a range of FI schedules from 5 to 180 sec in duration. Both the amount of chewing per session and the relative time spent chewing were bitonically related to reinforcement rate. In Experiment 3, schedule-induced chewing that had been acquired under a response-dependent schedule was found to persist under a response-independent schedule. Induced wood-chewing resembles other induced behaviors in important respects, but quantitative differences are also apparent.

Resistance to the response-decrementing effects of response-independent reinforcement produced by delay and non-delay schedules of reinforcement

In two experiments, animals were initially exposed to response-dependent schedules of food before exposure to response-independent reinforcement matched for overall rate and temporal distribution of reinforcers to the preceding condition. In Experiment I, response decrements during the response-independent phase were smaller after delayed reinforcement training than after a comparable immediate reinforcement schedule, for both doves and rats. In Experiment II variable-interval and variable-ratio schedules, both with either immediate or delayed reinforcement, were used with rats. Both the delayed reinforcement schedules produced resistance to subsequent response-independent reinforcement, but response decrements were larger after either of the immediate reinforcement conditions. It was concluded that the critical factor in response maintenance under response-independent reinforcement was the type of response-reinforcer contiguities permitted under the response-dependent schedule rather than perception of response-reinforcer “contingencies”. If the response-dependent schedule was arranged so that behaviours other than a designated operant (key pecking or lever pressing) could be contiguous with food, responding was maintained well under response-independent schedules.

Positive Contrast Following Extinction in a Response-Independent Schedule

Four rats were trained on either a mult VI VI or mult VI VTN schedule for food. VTN refers to a schedule in which free food is delivered and there is no response lever available. When extinction was introduced into one component (the VTN component for that group), strong positive contrast effects were noted, i.e., there were increases in response rate in the unaltered component. These results did not support Hinson and Staddon’s (1978) behavioral competition explanation of contrast.

Crows learn not to respond under response-independent reinforcement

Seven fish crows were trained to respond under either fixed- or variable-interval schedules. Subsequently, the response dependency was systematically eliminated and then reinstated. The distribution of reinforcers in time was the same under the response-independent schedules as had prevailed under the response-dependent schedules. Responding was successfully maintained for all birds when the response dependency was in effect, but it eventually ceased under the response-independent procedure. Responding resumed when the response dependency was reinstated. Terminal patterns of responding under each of the interval schedules were similar to those displayed by pigeons. However, compared to pigeons, fish crows showed substantially less responding under response-independent procedures. An explanation of this result is offered that stresses differences between crows and pigeons in their natural feeding patterns in relation to the type of response (pecking) required to obtain food in the experiment.