Transfer of conditioned appetitive stimuli to conditioned aversive excitatory and inhibitory stimuli

The transfer of Pavlovian appetitive stimuli to Pavlovian aversive stimuli was examined in three experiments. In Experiment 1, rats received appetitive (Ap) conditioning designed to establish a flashing-light stimulus as either a CS+, CSo, or CS? for food, or to maintain it as a novel stimulus for US-alone subjects. Then, the stimulus was employed as a signal for weak shock in conditioned-emotional-response (CER) training. Both acquisition and extinction results showed that the ApCS+ facilitated and the ApCS? retarded aversive excitatory conditioning relative to the ApCSo and US-alone controls. Experiment 2 replicated the findings of Experiment 1 with both a moderate and a severe shock in CER training. In Experiment 3, different groups received the same appetitive conditioning as before, but to a flashing-light stimulus which was then employed as a signal for no shock in CER training. The ApCS? facilitated and the ApCS+ retarded aversive inhibitory conditioning relative to ApCSo and US-alone controls. Collectively, these findings establish that, in Pavlovian conditioning, transfer of an appetitive CS to an aversive excitor or inhibitor is facilitated by maintaining the initial conditioning contingency.     

Transfer of the signaling properties of aversive CSs to an instrumental appetitive discrimination

Rats received Pavlovian conditioning in which, based on a shock US, white noise was established for different groups as an aversive CS+, CSo, or CS?. Then, half of each group received the CS contingent upon either the food-reinforced or nonreinforced response in an easy, choice discrimination. Correct responses, i.e., number of reinforcements, to criterion showed that a CS+ for the reinforced response facilitated learning, whereas a CS? retarded learning; conversely, a CS+ for the nonreinforced response retarded learning, whereas a CS? facilitated learning. The same contingency difference occurred with errors to criterion for CS? subjects but was obscured for CS+ subjects apparently by an avoidance-producing effect of the CS+. In support of the generality of the transfer effect, Z-score transforms of the correct-response data showed that the magnitude of transfer was comparable to that obtained in more difficult discriminations. Collectively, the findings indicate that an aversive CS can function as a transformed signal for the presence (CS+) or absence (CS?) of an appetitive reinforcer and that the signal's control of behavior is via a within-chain mediational process.     

On the directionality of key pecking during signals for appetitive and aversive events

Pigeons were exposed to a signal paired with either blackout or blackout plus shock and to another signal paired with food superimposed on a baseline of concurrent variable-interval reinforcement of pecks on two keys. The signals were changes of color of one of the two keys. The rate of pecking both keys during the signal paired with blackout or blackout plus shock was lower than the baseline rate of pecking (a conditioned emotional response), but the decrease in pecking was greater on the signal key. When the intensity of shock was increased, the rate of pecking did not decrease further on the signal key but did decrease on the other key. Rate of pecking during the signal paired with food increased sharply on the signal key (an autoshaping effect) and decreased sharply on the other key. These results support a view that there are two effects of the interaction between classical and instrumental conditioning, a stimulus-directed effect and a generalemotional effect.     

Effects of personal competence on the significance of interpersonal agreement and disagreement: Physiological activation and social evaluations

Two psychological theories, affect-reinforcement theory and consistency theory, were compared for their usefulness in predicting arousal during a social episode. One-hundred twelve males met in pairs to discuss their attitudes on one topic. Half of the subjects rated themselves as competent to defend the correctness of their attitude; the other half rated themselves as not competent to defend the correctness of their position on the specific topic under discussion. The topic was selected by the experimenter such that half of the pairs were in agreement in their attitude, while the other half of pairs had opposing attitudes for the topic. The three factors (competence of Person A, competence of Person B, and similarity of attitude) were crossed to produce eight conditions. Skin conductance was continuously recorded throughout the social interaction. Following the discussion period, subjects rated each other on the Evaluative-Behavioral Attraction Measure. Skin conductance data supported the affect-reinforcement hypothesis with a significant interaction between self-rated competence and similarity of attitude factors (p < .05). Hearing disagreement from the other person was highly arousing when a subject said he was competent to present his position on the topic. Other significant effects for physiological activation during the social episode, which were not predicted, are consistent with the affect-reinforcement theory. There was no significant effect for the attraction measure.     

Signaling and affective functions of conditioned aversive stimuli in an appetitive choice discrimination: US intensity effects

Different groups of rats received Pavlovian aversive conditioning in which US-shock intensity (0.25–1.0 mA) and CS-US correlation (+, 0, ?) were factorially varied. Then, the CS was administered for each group contingent upon the reinforced response in an appetitive choice discrimination. Absolute and ratio measures of speed of running in the presence of the CS showed that, at the start of discrimination training, CS+ suppressed and CS- facilitated performance. However, later in training but prior to any evidence of choice learning, these speed effects reversed, with the magnitude of both the initial and reversed effects being a positive function of US intensity. Consistent with the reversal of speeds, associative (choice) measures showed that CS+ facilitated and CS- retarded discrimination learning relative to CSo and, within limits, these effects were also amplified by stronger USs. The findings suggest that a CS has both affective (motivational) and signaling (associative) functions and that both are influenced by US intensity; however, the CS's affective property is rapidly extinguished in the presence of a hedonicly different reinforcer, while leaving the CS's signaling property largely intact. Hence, the CS functions as a transformed signal for the new (appetitive) reinforcer and facilitates or retards learning by mediating the reinforcer's presence (CS+) or absence (CS-).     

Interactive effects of deprivation in the albino rat

The interactive effects of feeding and drinking schedules were investigated in three experiments. Twenty-four hour water-deprived rats consumed their entire obligatory water intake prior to feeding, whereas 24-hr food-deprived rats consumed only small quantities of food prior to drinking. This drinking was apparently due to a shift of water stores rather than an actual negative water balance. Experiment 3 investigated the effects of 24, 48, or 72 hr of water, food, or total deprivation. Water-deprived rats did not adequately suppress food intake and became thirstier than totally deprived rats. The effects of total deprivation were essentially identical to those of food deprivation. These experiments indicate the degree to which deprivation schedules impose restrictions on the reinforcement parameters of behavioral experiments.     

Wage rate,nonlabor income,and labor supply in rats

Thirsty rats pressed a lever for water under fixed-ratio schedules, with or without free water at the start of the 1-hr session. Total water intake fell steadily as the fixed-ratio requirement increased; when the fixed-ratio requirements covered a relatively broad range, total lever presses rose and then fell as the requirement increased. Free water decreased total lever presses but increased total intake, especially at the higher fixed-ratio requirements; its effect on total intake proved relatively hard to detect, but grew more apparent as the amount of free water increased. The results conformed more closely to a recent revision of the conservation model than to the original model. By viewing milliliters per press as a wage rate, and free water as nonlabor income, results are brought to bear on predictions derived from economic labor supply theory. In economic terms, rising wage rates were accompanied by a rise followed by a fall in total labor supply, but a steady rise in total income, in conformity with the backward bending labor supply curve. Nonlabor income cut the supply of labor but raised total income, especially at the lower wage rates.     

Pavlovian processes and response competition as determinants of avoidance response-prevention effects

Two experiments investigated the facilitation of avoidance extinction by exposure to lengthy (5-sec) shock during avoidance response prevention. In Experiment 1, animals exposed to light only or to light-shock pairings during response prevention showed equal facilitation of extinction relative to shock-only animals or to animals receiving no response prevention. Preshock rearing, directly antagonistic to the avoidance response, developed for shocked animals during response prevention and persisted during extinction for light-shock animals. Immediately before extinction, half of each group was permitted a single escape from a light-shock compound by means of the response previously required for avoidance. The only effect was upon the extinction performance of light-shock animals. Rearing was eliminated and extinction responding increased to a level far above that for any of the other animals. Experiment 2 demonstrated that the shock-only treatment affected the extinction performance and rearing of nonescape and escape animals in a manner entirely equivalent to the effects of the light-shock treatment of Experiment 1, provided stimulus conditions (light absent) were the same for all experimental phases. Thus, lengthy shock during avoidance response prevention simultaneously leads to the acquisition of competing behavior and enhances control by a warning signal or contextual stimuli over the avoidance response. Implications for the CS-only response-prevention treatment and the transfer of aversive control are discussed.     

A process analysis of the effects of performance-contingent rewards on intrinsic motivation

In this study, the effects of performance-contingent rewards on intrinsic motivation were examined in comparison to no-reward controls receiving identical performance feedback. A path analytic process analysis was conducted to examine the mediation of reward effects on subsequent task interest. It was hypothesized that competence valuation, or the personal importance of doing well, would be an important mediator of interest in situations where performance feedback was available. Rewards were predicted to affect interest by influencing an individual's valuation of competence, and by altering the competence valuation mediation process. In addition, achievement orientation was hypothesized to interact with reward in affecting importance and the mediation process. Prior to performing an interesting puzzle, high school students were offered a performance-contingent reward, and then indicated how personally important it was to do well. After doing three puzzles, all subjects received positive feedback regarding their performance. Multiple regression analyses indicated that importance was affected by the experimental variables, and had a positive causal impact on subsequent intrinsic motivation. It was found that the promise of performance-contingent reward positively affected importance for low achievers relative to high achievers, and that the mediation of subsequent intrinsic interest by importance differed according to reward by achievement combinations. Additionally, a direct effect revealed that performance-contingent rewards significantly enhanced interest, relative to no-reward controls receiving identical performance feedback.     

Stimulus generalization of auto-shaped key-pecking following interdimensional and extradimensional training

In three experiments, groups of pigeons were tested for wavelength generalization of auto-shaped key-pecking following different types of training. In Experiment I, one group received auto-shape trials with a 555-nm CS. Another group received auto-shape trials with a 555-nm CS and a white CS. A third group received auto-shape trials with a 555-nm CS and a white CS, except the white CS was nonreinforced. The third group yielded the sharpest gradient, whereas the second group yielded the flattest gradient. In Experiment II, one group received auto-shape trials with a 555-nm CS. A second group received auto-shape trials with a 555-nm CS and a compound CS consisting of a vertical white line on a 555-nm background. A third group received auto-shape trials with a 555-nm CS and a compound CS, except that the compound was nonreinforced. The third group yielded the sharpest wavelength gradient, whereas the second group yielded the flattest. In Experiment III, exposure differences to 555 nm in Experiment II resulting from differential speeds of auto-shape acquisition were controlled by the use of an ITI manipulation. Amount of exposure to 555 nm was shown not to be responsible for the results of Experiment II.     

An experimental analysis of aversive imagery versus electrical aversive conditioning in the treatment of chronic alcoholics

A series of three experiments is described comparing an aversive imagery and an electrical escape conditioning procedure in the treatment of chronic alcoholics. Treatment effects were objectively measured by recording subjects' alcohol consumption in a semi-naturalistic laboratory setting. In contrast to conventional group outcome studies, the use of single-subject methodology provided a fine-grained analysis of individual response patterns. The aversive imagery and escape conditioning methods did not differ from each other, and were relatively ineffective in suppressing alcohol intake. In contrast, a punishment procedure in which shock was contingent on drinking did effectively suppress drinking. The data suggest that alcoholics can control their drinking by self-administered shock. The implications for the analysis and treatment of alcoholics are discussed.     

Trials per problem and age as factors in learning set formation of children

Discrimination learning set performance was examined in preschool children as a function of age and number of trials per problem. Subjects 3, 4, 5, and 6 years old were trained over three 72-trial sessions. Half of the children at each age were given problems three trials in length, and half received 12-trial problems. As predicted, younger children (3 and 4-year-olds) performed significantly better for 12 than for three trials per problem, whereas no differences in performance were evident for older children. Response pattern analyses revealed that younger children, especially those receiving less exposure within problems, produced a higher proportion of stimulus alternation and position determined response sequences than did older children. These results contradict the commonly held assumption that learning set acquisition is simply a function of the total number of trials presented and indicate that the amount of exposure to individual problems is a factor in problem solution for young human subjects.     

The effects of response-reinforcer contingency on time allocation in the open field

The present experiment explores the effects of the response (1-sec occupancy of a target area in an open field)—reinforcer (intracranial stimulation) contingency on time allocation in the open field in rats. The probability of reinforcement given a response (X) and the probability of reinforcement given the absence of a response (Y) were varied randomly across sessions within a subject. The following (X, Y) values were utilized: (.05, 0), (.15, 0), (.25, 0), (.15, .05), and (.15, .15). The results of this experiment indicate that rate of acquisition of time allocation preference is uniformly rapid during all contingency treatments wherein Y = 0 and is negatively related to the value of Y when X = .15. The relationship between the asymptote of the time allocation acquisition function and the value of X (when Y = 0) is positively sloped and negatively accelerated, while the relationship between asymptote and the value of Y (when X = .15) is negatively sloped with zero acceleration. Proposed contingency metrics are evaluated.     

Reinforcement contrast effects on the rewarding and aversive components of intracranial stimulation

Rats performing a free-operant locomotor response in a shuttlebox to initiate and then escape medial diencephalic stimulation were tested daily on a randomized sequence of three stimulation intensities. In spite of a 1-hr interval between stimulation intensity changes, substantial and graded reinforcement contrast effects were obtained. “Elation” effects were obtained both on the rewarding (latency to initiate) and the aversive (latency to escape) components of stimulation whereas “depression” effects were found only on the measure of reward.     

The effect of Pavlovian stimuli on the acquisition of a new response

Three experiments explored the effects of response dependent stimuli which have had different types of contingent relationships with positive reinforcement. Results showed consistent differences in the effects of response dependent appetitive Pavlovian CS + s, CS ? s, and truly random control (TRC) stimuli on the acquisition of a new response. These differences were shown in both a free operant and a discrete-trial learning situation. Appetitive Pavlovian CS?s consistently produced lower levels of responding than did TRC stimuli, even in an experimental situation free of possible contrast effects. The results of these experiments extended a contingency analysis of acquired associations to appetitive conditioning and provided a clear demonstration of a conditioned reinforcement effect against a variety of control procedures.     

Interference effects on preschool children's learning sets

Four experiments investigated interference in 5-year-olds' learning sets. Experiment 1 manipulated intertrial and interproblem intervals, showing that increased intertrial intervals retarded performance. Long interproblem intervals interacted with short intertrial intervals to produce performance facilitation. Experiment 2 investigated interpolations within problems with either similar or dissimilar stimulus presentations. Similar stimuli caused greater performance decrements than dissimilar. Experiment 3 hypothesized that the within-subjects design of Experiment 1 masked interproblem interval effects. Testing between-subjects established that increased interproblem delays facilitate performance. In Experiment 4 interproblem delays were further tested in a series of shifts within and between dimensions. Increased delays more greatly benefited shifts within dimensions. It is concluded that intertrial and interproblem intervals affect learning set performance differentially. Intertrial delays result in performance deterioration due in part to interference. Interproblem delays facilitate performance at least in part by providing the opportunity for suppression of proactive interference, and perhaps in part by providing the opportunity for constructive cognitive processing.     

Distance estimates of children as a function of acquisition and response activities

Second and sixth graders (8 and 12 years of age, respectively) experienced a large-scale environment either actively or passively followed by a distance estimation task requiring either active or passive activity. Second graders were most accurate in those conditions where acquisition and response activities were congruent. These children significantly overestimated distances in the passive acquisition-active response condition. Sixth graders were equally accurate across all four experimental conditions. Results are discussed in terms of the complex interaction between acquisition factors and task demands which influence interpretations about spatial representations.