Partial avoidance contingencies: Absolute omission and punishment probabilities

Avoidance contingencies were defined by the absolute probability of the conjunction of responding or not responding with shock or no shock. The “omission” probability (ρ₀₀) is the probability of no response and no shock. The “punishment” probability (ρ₁₁) is the probability of both a response and a shock. The traditional avoidance contingency never omits shock on nonresponse trials (ρ₀₀=0) and never presents shock on response trials (ρ₁₁=0). Rats were trained on a discrete-trial paradigm with no intertrial interval. The first lever response changed an auditory stimulus for the remainder of the trial. Shocks were delivered only at the end of each trial cycle. After initial training under the traditional avoidance contingency, one group of rats experienced changes in omission probability (ρ₀₀>0), holding punishment probability at zero. The second group of rats were studied under different punishment probability values (ρ₁₁>0), holding omission probability at zero. Data from subjects in the omission group looked similar, showing graded decrements in responding with increasing probability of omission. These subjects approximately “matched” their nonresponse frequencies to the programmed probability of shock omission on nonresponse trials, producing a very low and approximately constant conditional probability of shock given no response. Subjects in the punishment group showed different sensitivity to increasing absolute punishment probability. Some subjects decreased responding to low values as punishment probability increased, while others continued to respond at substantial levels even when shock was inevitable on all trials (noncontingent shock schedule). These results confirm an asymmetry between two dimensions of partial avoidance contingencies. When the consequences of not responding included occasional omission of shock, all subjects showed graded sensitivity to changes in omission frequency. When the consequences of responding included occasional shock delivery, some subjects showed graded sensitivity to punishment frequency while others showed control by overall shock frequency as well.     

Response-outcome contingency: Behavioral and judgmental effects of appetitive and aversive outcomes with college students

In two experiments, positive, negative, and zero response-outcome contingencies were responded to and rated by college students under a free-operant procedure. In Experiment 1, outcomes were either neutral or were associated with point gain. In Experiment 2, subjects were administered different outcome treatments: neutral outcomes, outcomes associated with money gain, or outcomes associated with money loss. In both experiments, subjects' judgments of response-outcome contingency and their operant responses were each strong linear functions of ΔP, the difference between the probability of an outcome given a response and the probability of an outcome given no response. Appetitive and aversive outcomes produced opposite and symmetrical response patterns. In Experiment 1, no differences in ratings occurred with neutral or appetitive outcomes; however, in Experiment 2, more potent appetitve outcomes led to somewhat more extreme ratings than either neutral or aversive outcomes. Increasing outcome probability produced only a slight bias in ratings of noncontingent problems in Experiment 1 and no bias in Experiment 2. Contrary to predictions derived from an analysis of superstitious behavior, increasing outcome probability in noncontingent problems decreased operant responding when outcomes were appetitive and increased operant responding when outcomes were aversive. Trend analyses revealed that Δ P was superior to several other metrics in predicting subjects' estimates of contingency and the behavioral effects of contingency. Operant responding was in closer accord with matching predictions than with maximizing predictions.     

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.

     

Two-component schedules of differential-reinforcement-of-low-rate

Two-component schedules of differential-reinforcement-of-low-rate were presented, where the contingencies specified separately two minimum interresponse times, t₁ and t₂, required for reinforcement, depending on whether the interresponse time was initiated by, in one case, a reinforced response (t₁) or, in the other, a nonreinforced response (t₂). A distinctive pattern of responding developed on each of the two contingencies. Duration of an interresponse time approximated t₁ when the t₁ contingency was in effect, and t₂ when the t₂ contingency was in effect. This relationship persisted even when t₂ was shorter than t₁, and responding at a higher rate on the t₁ contingency would have greatly increased the rate of reinforcement. Increasing the value of t₂ resulted in both longer interresponse times on the t₁ contingency, and a higher probability of a response-burst on those occasions when the contingency switched from t₁ to t₂. The results indicated that both reinforced and nonreinforced responses functioned as discriminative events in determining the duration of following interresponse times.     

Avoidance of 20% carbon dioxide-enriched air with humans.

Four college students were exposed to a Sidman avoidance procedure to determine if an avoidance contingency involving 20% carbon dioxide-enriched air (CO2) would produce and maintain responding. In Phase 1, two conditions (contingent and noncontingent) were conducted each day. These conditions were distinguished by the presence or absence of a blue or green box on a computer screen. In the contingent condition, CO2 presentation were delivered every 3 s unless a subject pulled a plunger. Each plunger pull postponed CO2 presentations for 10 s. In the noncontingent condition, CO2 presentations occurred on the average of every 5 min independent of responding. Following stable responding in Phase 1, condition-correlated stimuli were reversed. In both conditions, plunger response rate was high during the contingent condition and low or zero during the noncontingent condition. Furthermore, subjects avoided most CO2 presentations. However, CO2 presentations did not increase verbal reports of fear. Overall, the results from the present study suggest that CO2 can be used effectively in basic studies of aversive control and in laboratory analogues of response patterns commonly referred to as anxiety.     

Self-punitive behavior in humans: Effects of a self-fulfilling prophecy

Human subjects were exposed to contingencies which programmed aversive tones (100 db). Two types of contingencies were employed: self-confirming (i.e., self-fulfilling prophecies), in which the aversive tone was occasioned by the prediction it was about to occur; and self-disconfirming, in which the tone was probable when subjects predicted it would not occur. Experiments 1 and 2 used a modified classical conditioning paradigm, and demonstrated that a self-confirming contingency maintained reliable self-punitive responding, i.e., subjects consistently predicted and therefore obtained tones on every trial. Subjects in Experiment 3 were instructed to express predictions continuously throughout four sessions to ensure adequate sampling of the various predictions. Subjects exposed to a self-disconfirming contnngency reliably evidenced awareness of the contingency in effect (judged by answers on a postexperimental questionnaire), whereas subjects exposed to a self-confirming contingency failed to show effective avoidance behavior or contingency awareness. Experiment 4 investigated free-operant self-punitive behavior, utilizing a single prediction response button, which subjects depressed repeatedly. Subjects were exposed to either periodic or aperiodic punishment schedules over as many as four sessions. In general, more persistent self-punitive responding was found in the groups receiving periodic punishment. The results from the four experiments show that self-confirming contingencies can effectively prolong self-punitive responding in human subjects. The findings are consistent with a blocking interpretation of self-punitive behavior, which asserts that when an aversive event is already predicted by stimuli in the situation (including temporal cues), the association between a response and punishment is impaired, and self-punitive responding is likely to be maintained. An integration of human and animal self-punitive research is proposed.     

Summation of excitatory and inhibitory control produced by traditional tone-shock contingencies and autocontingencies

Previous research has demonstrated that rats can use unsignaled shock to predict subsequent periods free from shock. This shock-no shock stimulus arrangement, termed an autocontingency, has appeared less likely to exert behavioral control when a traditional tone-shock contingency was simultaneously available. The present research examined the generality of CS-US contingency dominance in a conditioned suppression paradigm by using a summation test in which “probe” stimuli derived from tone-shock contingencies were superimposed upon responding maintained by an autocontingency. In experiment 1, an inhibitory CS accelerated responding only when responding was normally suppressed by the autocontingency. In experiment 2, an excitatory CS failed to yield conditioned suppression during an inhibitory (accelerative) period produced by the autocontingency. Unlike our previous findings (e.g., Davis, Memmott & Hurwitz, 1975), these results do not support a general notion of tone-shock contingency dominance over autocontingencies. Behavioral control by autocontingencies appears robust and “holds its own” in summation with both excitatory and inhibitory CSs derived from traditional contingencies.     

Judgements of a 2 × 2 contingency table: Sequential processing and the learning curve

Shanks (1985) has used a video game to investigate how subjects estimate the effect of their behaviour in a task defined by a 2×2 contingency table. The subjects were able to distinguish positive and negative contingencies from zero contingencies. In addition, they showed a learning curve and a bias to rate zero contingencies with a high outcome density higher than low-density zero contingencies. He interpreted these data as being consistent with associative models derived from animal learning. In Experiment 1 we replicated these results using a task and instructions similar to his. In a second experiment we showed that the subjects' tendency to overestimate high-density zero contingencies did not arise because the “game” was so difficult that it interfered with processing the events. In this experiment subjects were given tables of the outcome frequencies that had been determined by the earlier subjects. These subjects were, if anything, less accurate in rating the zero contingencies. We point out several logical problems with Shanks's initial task. The task did not represent a true 2×2 contingency, and aspects of it were physically impossible. In Experiment 3 we modified the task to represent a true 2×2 contingency. Using this task, we found a similar pattern of results, except that there was no evidence of the learning curve predicted by the associative models. We conclude that there is little in our data to rule out a “rule-based” analysis of contingency judgements.     

Effects of response variability on the sensitivity of rule-governed behavior

Two experiments examined the relation between response variability and sensitivity to changes in reinforcement contingencies. In Experiment 1, two groups of college students were provided complete instructions regarding a button-pressing task; the instructions stated “press the button 40 times for each point” (exchangeable for money). Two additional groups received incomplete instructions that omitted the pattern of responding required for reinforcement under the same schedule. Sensitivity was tested in one completely instructed and one incompletely instructed group after responding had met a stability criterion, and for the remaining two groups after a short exposure to the original schedule. The three groups of subjects whose responding was completely instructed or who had met the stability criterion showed little variability at the moment of change in the reinforcement schedule. The responding of these three groups also was insensitive to the contingency change. Incompletely instructed short-exposure responding was more variable at the moment of schedule change and was sensitive to the new contingency in four of six cases. In Experiment 2, completely and incompletely instructed responding first met a stability criterion. This was followed by a test that showed no sensitivity to a contingency change. A strategic instruction was then presented that stated variable responding would work best. Five of 6 subjects showed increased variability after this instruction, and all 6 showed sensitivity to contingency change. The findings are discussed from a selectionist perspective that describes response acquisition as a process of variation, selection, and maintenance. From this perspective, sensitivity to contingency changes is described as a function of variables that produce response variability.     

Optimal Self‐esteem is Contingent: Intrinsic Versus Extrinsic and Upward Versus Downward Contingencies

We argue that noncontingent, unconditional self‐esteem is not optimal but defensive. We introduce the concept of intrinsic contingency, where self‐esteem is affected by whether one's actions are self‐congruent and conducive to personal growth. Whereas external contingencies, especially social and appearance, were negatively correlated with authenticity, self‐compassion, and personal well‐being, intrinsic contingencies were positively correlated with these measures, and uncorrelated with aggression and self‐esteem instability. Participants with high intrinsic contingency rated higher on measures of psychological adaptiveness than noncontingent participants. In addition, we distinguish upward from downward contingencies, the latter being more harmful in case of external contingencies but not for intrinsic contingencies. We conclude that intrinsic contingency, rather than noncontingency, may reflect true self‐esteem as implied in self‐determination theory. Copyright © 2011 John Wiley & Sons, Ltd.     

Lick-shock contingencies in the rat

Hungry rats were allowed to lick an 8% sucrose solution and then one of four lick-shock contingency conditions was superimposed on the licking baseline. These conditions were: free-operant avoidance, free shock, punishment, and no shock. From highest to lowest response rates, the groups fell in the order-avoidance, no shock, free shock, and punishment. Lick rates adjusted rapidly to introduction and removal of the contingencies. Post-shock responding was lowest in the punishment condition and highest in the free shock condition. No method was found simultaneously to equate shock frequency and separate response rates for the three shock contingency conditions. Only small, or no, reductions in shock rate occurred over sessions under the free-operant avoidance schedule when the shock-shock interval was 10 sec but large reductions occurred when the shock-shock interval was reduced to either 1 or 2 sec.     

An analysis of coordinated responding of pigeons

Experimental analyses of coordinated responding (i.e., cooperation) have been derived from a procedure described by Skinner (1962) in which reinforcers were delivered to a pair of subjects (a dyad) if both responded within a short interval, thus satisfying a coordination contingency. Although it has been suggested that this contingency enhances rates of temporally coordinated responding, limitations of past experiments have raised questions concerning this conclusion. The present experiments addressed some of these limitations by holding the schedule of reinforcement (Experiment 1: fixed ratio 1; Experiment 2; variable interval 20 s) constant across phases and between dyad members and by varying, in different conditions, the number of response keys (one to three) across which coordination could occur. Greater percentages of coordinated responding occurred under the coordinated-reinforcement phases than under independent-reinforcement phases in most conditions. The one exception during the one-key condition of Experiment 1 appeared to be a consequence of variability introduced by the independent-reinforcement phase procedure. Furthermore, coordination percentages decreased with increasing response options under both schedules. These results confirm and extend the finding that coordination contingencies control higher rates of temporally coordinated responding than independent-reinforcement contingencies do.     

Discrimination of response-reinforcer and response-stimulus contingencies in pigeons

For three pigeons (Experiment 1), the presentation of a red response key ended with a food presentation either following two responses separated by at least 10 seconds (a DRL contingency) or following a 10-second response-free period (a DRO contingency). For three other birds (Experiment 2), a brief stimulus presentation terminated the DRL and DRO contingencies. A white side key was presented next and ended with response-dependent food following one contingency and a timeout following the other. Since the contingency on the red key was unsignaled, differential responding on the white side key could indicate that the two response-reinforcer relations had been discriminated. In Experiment 1, the red-key duration and number of responses influenced white-key responding following the contingency that predicted the timeout. A response-initiated DRO was instated, and the influence of red-key duration and response number on white-key responding was diminished. In both experiments, the 10-second time criterion in both contingencies was varied from 0.34 second to 10 seconds. Even at short time intervals the DRO and DRL contingencies were readily discriminated. Pigeons tended to class the two contingencies according to a rule that did not involve simply stimulus duration, numbers of responses, or even the time between a response and its consequence.     

Interpersonal contingencies: Performance differences and cost-effectiveness

Three reinforcement contingencies were compared with regard to performance differences and cost-effectiveness (i.e., responses per unit reinforcer). Pairs of college students were studied under individual, cooperative, or competitive contingencies using a concurrent setting that included one of these three contingencies as one alternative and a lower paying individual contingency as the other alternative. With the individual and the cooperative contingencies, overall response rates were typically high; under competitive contingencies the overall response rates were substantially lower. Subjects responded at very high rates when competing, but chose not to compete most of the time. Competition and cooperation produced the most cost-effective responding, assessed as the number of responses made per $.01 of reinforcer. High overall rates of competitive responding were obtained when the contests were longer and the lower paying alternative contingency was not available.     

Judgment of contingency in depressed and nondepressed students: sadder but wiser?

How are humans' subjective judgments of contingencies related to objective contingencies? Work in social psychology and human contingency learning predicts that the greater the frequency of desired outcomes, the greater people's judgments of contingency will be. Second, the learned helplessness theory of depression provides both a strong and a weak prediction concerning the linkage between subjective and objective contingencies. According to the strong prediction, depressed individuals should underestimate the degree of contingency between their responses and outcomes relative to the objective degree of contingency. According to the weak prediction, depressed individuals merely should judge that there is a smaller degree of contingency between their responses and outcomes than nondepressed individuals should. In addition, the present investigation deduced a new strong prediction from the helplessness theory: Nondepressed individuals should overestimate the degree of contingency between their responses and outcomes relative to the objective degree of contingency. In the experiments, depressed and nondepressed students were present with one of a series of problems varying in the actual degree of contingency. In each problem, subjects estimated the degree of contingency between their responses (pressing or not pressing a button) and an environmental outcome (onset of a green light). Performance on a behavioral task and estimates of the conditional probability of green light onset associated with the two response alternatives provided additional measures for assessing beliefs about contingencies. Depressed students' judgments of contingency were surprisingly accurate in all four experiments. Nondepressed students, on the other hand, overestimated the degree of contingency between their responses and outcomes when noncontingent outcomes were frequent and/or desired and underestimated the degree of contingency when contingent outcomes were undesired. Thus, predictions derived from social psychology concerning the linkage between subjective and objective contingencies were confirmed for nondepressed students but not for depressed students. Further, the predictions of helplessness theory received, at best, minimal support. The learned helplessness and self-serving motivational bias hypotheses are evaluated as explanations of the results. In addition, parallels are drawn between the present results and phenomena in cognitive psychology, social psychology, and animal learning. Finally, implications for cognitive illusions in normal people, appetitive helplessness, judgment of contingency between stimuli, and learning theory are discussed.     

Stereopsis with opposite contrast contours

The effects of incidental stimuli, defined as visual stimuli not under verbal control, upon a selection task were observed as a function of feedback contingency. Ss judged letter pairs to be valid or invalid completions of preceding letter parts. During the presentation of the letter parts, the response pair or an alternative pair of letters was intermittently presented at a threshold value individually determined for each S. One group of Ss received a light feedback of performance contingent upon responding to the incidental stimuli; whereas a second group received a random noncontingent feedback. The results indicated: (a) both groups responded to the incidental stimuli; (b) feedback contingency had no effect on frequency of responding to the incidental stimuli; (c) frequency of responding to the incidental stimuli remained constant over 32 trials.     

Response additivity: effects of superimposed free reinforcement on a variable-interval baseline

Three experiments examined the effects of superimposing free reinforcement (Free VI 30-sec) on behavior maintained by a response dependent mult VI 2-min VI 2-min schedule of reinforcement. Experiment I used pigeons as subjects, key pecking as the response, and colors of response key as the stimuli associated with the multiple-schedule components. When free reinforcement was added during only one component (Differential condition) a large and highly significant increase in response rate developed in this component. Adding free reinforcement during both components (Nondifferential condition) produced smaller and far less-consistent effects. An entirely different pattern of results was obtained in two subsequent experiments, where similar procedures and reinforcement conditions were used with rats as subjects and bar pressing as the response. In both Experiments II and III, response rates decreased to the stimulus associated with added free reinforcement in the Differential condition. These findings are interpreted as the result of interactions between behavior maintained by response-reinforcer contingencies and behavior maintained by stimulus-reinforcer contingencies. As such, they support the main assumption of an autoshaping theory of behavioral contrast, that additivity of responding generated by the two kinds of contingency can occur only in situations favorable to autoshaping.     

Responding under positive and negative response contingencies in pigeons and crows

Four crows were trained to key peck for food. Then, they were exposed to a positive response contingency that required them to peck the key when it was illuminated briefly (the trial) in order to receive food. This procedure resulted in consistent within-trial pecking. When the contingency changed so that food was presented at the end of a trial when no response occurred, but the trial terminated immediately and food was omitted when a response occurred (negative response contingency), responding decreased markedly. Eight pigeons were studied under the same change in contingencies. These birds varied in their response histories from naive to having several years' experience. The previously naive pigeons also showed rapid declines in responding under the negative contingency; the responding of the birds with extended training histories declined much more slowly. Eventually, however, six of the eight pigeons showed little or no responding under the negative contingency, while they responded consistently when re-exposed to the positive contingency. These findings question the power and the generality of the negative automaintenance phenomenon.     

Causal inferences as perceptual judgments

We analyze how subjects make causal judgments based on contingency information in two paradigms. In the discrete paradigm, subjects are given specific information about the frequency a, with which a purported cause occurs with the effect; the frequency b, with which it occurs without the effect; the frequency c, with which the effect occurs when the cause is absent; and the frequency d, with which both cause and effect are absent. Subjects respond toP ₁ =a/(a+b) andP ₂ =c/(c+d). Some subjects’ ratings are just a function ofP ₁, while others are a function of ΔP =P ₁ -P ₂. Subjects’ postexperiment reports are accurate reflections of which model they use. Combining these two types of subjects results in data well fit by the weighted ΔP model (Allan, 1993). In the continuous paradigm, subjects control the purported causes (by clicking a mouse) and observe whether an effect occurs. Because causes and effects occur continuously in time, it is not possible to explicitly pair causes and effects. Rather, subjects report that they are responding to the rate at which the effects occur when they click versus when they do not click. Their ratings are a function of rates and not probabilities. In general, we argue that subjects’ causal ratings are judgments of the magnitude of perceptually salient variables in the experiment.