Stimulus contributions to operant resurgence

In two experiments, pigeons were exposed to a three‐phase resurgence procedure (train Response A; extinguish Response A and train Response B; extinguish Response B). In the first experiment, the stimuli associated with phases were different, resulting in a resurgence procedure combined with an ABC renewal procedure. Presenting the novel stimulus, C, during extinction of both responses in the third phase resulted in minimal resurgence. Subsequently, substituting the original training Stimulus A for Stimulus C resulted in resurgence with all pigeons. In the second experiment, resurgence with the same stimuli present in all three phases of the resurgence procedure (AAA) was compared concurrently with a resurgence procedure in which the ABC renewal procedure used in Experiment 1 was superimposed. Substantially more resurgence occurred with the AAA procedure compared to the ABC procedure. Although ABC renewal in combination with the resurgence procedure generated some resurgence, such recurrent responding was attenuated relative to that observed when the stimulus conditions were constant across phases. Combined with earlier research showing the enhancing effects of combining resurgence and ABA renewal procedures, the present results elaborate on how stimuli correlated with certain behavioral histories affect the course of operant resurgence.     

Computer program to generate operant schedules

A computer program for programming schedules of reinforcement is described. Students can use the program to experience schedules of reinforcement that are typically used with nonhuman subjects. A cumulative recording of a student’s responding can be shown on the screen and/or printed with the computer’s printer. The program can also be used to program operant schedules for animal subjects. The program was tested with human subjects experiencing fixed ratio, variable ratio, fixed interval, and variable interval schedules. Performance for human subjects on a given schedule was similar to performance for nonhuman subjects on the same schedule.     

Resistance to change of operant variation and repetition

A multiple chained schedule was used to compare the relative resistance to change of variable and fixed four-peck response sequences in pigeons. In one terminal link, a response sequence produced food only if it occurred infrequently relative to 15 other response sequences (vary). In the other terminal link, a single response sequence produced food (repeat). Identical variable-interval schedules operated in the initial links. During baseline, lower response rates generally occurred in the vary initial link, and similar response and reinforcement rates occurred in each terminal link. Resistance of responding to prefeeding and three rates of response-independent food delivered during the intercomponent intervals then was compared between components. During each disruption condition, initial- and terminal-link response rates generally were more resistant in the vary component than in the repeat component. During the response-independent food conditions, terminal-link response rates were more resistant than initial-link response rates in each component, but this did not occur during prefeeding. Variation (in vary) and repetition (in repeat) both decreased during the response-independent food conditions in the respective components, but with relatively greater disruption in repeat. These results extend earlier findings demonstrating that operant variation is more resistant to disruption than is operant repetition and suggest that theories of response strength, such as behavioral momentum theory, must consider factors other than reinforcement rate. The implications of the results for understanding operant response classes are discussed.     

Human operant performance: Sensitivity and pseudosensitivity to contingencies

Undergraduates' button presses occasionally produced points exchangeable for money. Left and right buttons were initially correlated with multiple random-ratio (RR) and random-interval (RI) components, respectively. During interruptions of the multiple schedule, students filled out sentence-completion guess sheets describing the schedules, and points were contingent upon the accuracy of guesses. To test for sensitivity to schedule contingencies, schedule components were repeatedly reversed between the two buttons. Pressing rates were consistently higher in ratio than in interval components even when feedback for guesses was discontinued, demonstrating sensitivity to the difference between ratio and interval contingencies. The question was whether this sensitivity was based directly on the contingencies or whether it was rule-governed. For two students, when multiple RR RI schedules were changed to multiple RI RI schedules, rates became low in both components of the multiple RI RI schedule; however, subsequent prevention of point deliveries for the first few responses in any component produced high rates in that component. For a third student, response rates became higher in the RI component that provided the lower rate of reinforcement. In each case, performance was inconsistent with typical effects of the respective schedules with nonhuman organisms; it was therefore plausible to conclude that the apparently contingency-governed performances were instead rule-governed.     

Handwriting as an operant

An apparatus was designed to monitor handwriting behavior. Two subjects were studied under various schedules of monetary reinforcement for handwriting. The different schedules engendered and maintained distinctive response patterns but the rates of sustained responding did not vary across schedules. The development of fixed-interval performance following continuous reinforcement resembled the same transition in lower animals. In one subject, availability of reading material interacted with the schedule to determine response pattern. It was suggested that handwriting may be a more appropriate response for the experimental analysis of human behavior than the more frequently used button-pushing or lever-pulling responses.     

Aldactazide-induced consummatory and operant responding to sodium by rats.

The effects of intraperitoneal injections of Aldactazide-A on rats' consumption of water and saline solution (.51M NaCl) were tested in two experiments. During the treatment sessions, the rats showed a substantial increase in saline consumption and in lever pressing to a cue light to obtain the saline, as compared with their negligible intake before the injections and after the injections had been discontinued. The results indicate that both the drinkometer and operantbox measures are sensitive to the natroexigenic effects of Aldactazide.     

Top-down design for a system to control operant choice experiments

STATIONS, a FORTRAN program to control operant choice experiments, was developed based on the principles of top-down design and structured programming. As a consequence, the program consists of modules organized in a hierarchical fashion. Separate modules deal with different types of reinforcement schedules, such as variable ratio (VR) and variable interval (VI). These modules produce specific schedules with different parameters by using sequences of values read in at ran time and then randomly sampled. This form of organization permits modifications to be made via changes confined to one module without global repercussions. The clarity of structure that results from the application of top-down design and structured programming should enable future users to more easily adapt this package to suit their specific needs.     

Further evaluation of a nonsequential approach to studying operant renewal

Basic‐laboratory assessments of renewal may inform clinical efforts to maintain reduction of severe destructive behavior when clients transition between contexts. The contextual changes arranged during standard renewal procedures, however, do not necessarily align with those that clients experience during outpatient therapy. More specifically, clients transition between clinical (associated with extinction for target behavior) and home/community (associated with reinforcement for target behavior) contexts during outpatient treatment. Standard renewal assessments do not incorporate these contextual alternations during treatment. The present experiment aimed to directly compare renewal of rats' lever pressing following a standard (“sequential”) ABA renewal procedure (i.e., baseline in Context A, extinction in Context B, renewal test in Context A) and a “nonsequential” renewal assessment wherein treatment consisted of daily alternation between Context A (associated with reinforcement for lever pressing) and Context B (associated with extinction). Lever pressing renewed to a greater extent for rats in the Nonsequential group than for rats in the Sequential group, suggesting the contextual changes that clients experience during outpatient treatment for severe destructive behavior may be a variable that is important to consider in translational research on renewal. Potential implications of these findings for basic and clinical research on renewal are discussed.     

Feedback to attendants as a reinforcer for applying operant techniques

After varying lengths of baseline, initiation of a feedback system increased the daily use of operant training methods by non-professional hall personnel in a state institution for retarded children.     

An operant approach to teaching joint attention skills to children with autism

A lack of joint attention skills may constitute a core impairment in autism. In the present study, a training protocol was developed, based on the literature on joint attention and on behavioral interventions. The training was organized into a sequence of three main parts respectively aimed at establishing each of the following skills: (1) responding to joint attention bids, (2) engaging in turn‐taking activities based on joint attention skills, and (3) initiating joint attention. Two novel components were incorporated in the training: (a) a discrimination training procedure aimed at establishing the adult's nods as conditioned reinforcers and (b) tasks based on turn‐taking, where joint attention skills were targeted and reinforced. The study was conducted according to a single‐subject experimental design, in which joint attention skills were measured before and after intervention, using the “behavioral assessment of joint attention.” Four 3.5–5.5 year‐old children diagnosed with autism participated in the study. All four children completed the training successfully and made significant progress in engaging in joint attention and in initiating joint attention skills. Following the completion of training and at 1 month follow‐up, parents reported that their children used their skills in different settings. Moreover, at follow‐up, all four children were reported to engage in joint attention behaviors and to enjoy doing so. Copyright © 2009 John Wiley & Sons, Ltd.     

Correlation between self-reported rigidity and rule-governed insensitivity to operant contingencies

Adults were selected on the basis of their scores on the Scale for Personality Rigidity (Rehfisch, 1958a). Their scores served as a measure of hypothesized rule governance in the natural environment. Experiment 1 studied the effects of accurate versus minimal instructions and high versus low rigidity on performance on a multiple differential-reinforcement-of-low-rate (DRL) 4-s fixed-ratio (FR) 18 schedule. When the schedule was switched to extinction, accurate instructions and high rigidity were associated with greater perseveration in the response pattern subjects developed during the reinforcement phase. In Experiment 2, the effects of rigidity and of accurate versus inaccurate instructions were studied. Initially, all subjects received accurate instructions about an FR schedule. The schedule was then switched to DRL, but only half of the subjects received instructions about the DRL contingency, and the other half received FR instructions as before. Accurate instructions minimized individual differences because both high and low scorers on the rigidity scale earned points in DRL. However, when inaccurate instructions were provided, all high-rigidity subjects followed them although they did not earn points on the schedule, whereas most low-rigidity subjects abandoned them and responded appropriately to DRL. The experiments demonstrate a correlation between performances observed in the human operant laboratory and a paper-and-pencil test of rigidity that purportedly reflects important response styles that differentiate individuals in the natural environment. Implications for applied research and intervention are discussed.     

The operant conditioning of conversation

Human conversation is a natural place to begin the study of social responses. In a conversation, a number of individuals use one another's responses as cues for their own behavior. So long as a conversation is being held, the speakers must talk in some order. Four experiments were conducted to test whether differentially reinforcing a group of speakers can bring the order of speakers under experimental control. The results are all consistent with the hypothesis. The paper also devises and evaluates different procedures for studying conversational sequences and examines associated statistical problems.