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901.
W.Curtis Banks Kenneth R Stitt Harriet Ann Curtis Gregory V McQuater 《Journal of experimental social psychology》1977,13(5):452-463
Two experiments were conducted to investigate the effects of positive and negative reinforcements upon black college students. In the first experiment subjects received either positive or negative reinforcement from a black or a white Evaluator. Behavioral change (compliance) was greater in response to negative reinforcement from a black Evaluator than in response to negative reinforcement from a white Evaluator, while there were no divergent effects of Evaluator's Race upon compliance with positive reinforcement. The same pattern obtained in subjects' self-evaluations. The second experiment offered a test of the hypothesis that the objectivity of black Evaluators was perceived as greater than that of white Evaluators, and that a manipulation aimed at equating the Evaluators on objectivity would attenuate the effects of Evaluator's Race upon compliance and self-evaluation in response to negative reinforcement. These hypotheses were generally supported by the results. 相似文献
902.
903.
J M Harrison S D Iversen S R Pratt 《Journal of the experimental analysis of behavior》1977,28(3):243-251
Four rhesus monkeys were trained to respond on one key when a one-second noise burst was presented through one speaker and to respond on a second key when the noise burst was presented through a second speaker. The acquisition of stimulus control was studied under three conditions, in each of which the relationship between the sound source and the response-key positions varied: an adjacent condition in which the noise burst was presented through the key and a response on this key was reinforced; a reversed-adjacent condition in which the noise burst was presented through one key and responding on the other key was reinforced: and a nonadiacent condition in which responding on the key nearer the sound was reinforced. Under adjacent conditions, stimulus control developed within one or two sessions. Under reversed and nonadjacent conditions, 10 sessions were required for the development of control. The asymptote of correct responding was the same under each condition in all animals. 相似文献
904.
Duration and rate of reinforcement as determinants of concurrent responding 总被引:9,自引:9,他引:0
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The duration and frequency of food presentation were varied in concurrent variable-interval variable-interval schedules of reinforcement. In the first experiment, in which pigeons were exposed to a succession of eight different schedules, neither relative duration nor relative frequency of reinforcement had as great an effect on response distribution as they have when they are manipulated separately. These results supported those previously reported by Todorov (1973) and Schneider (1973). In a second experiment, each of seven pigeons was exposed to only one concurrent schedule in which the frequency and/or duration of reinforcement differed on the two keys. Under these conditions, each pigeon's relative rate of response closely matched the relative total access to food that each schedule provided. This result suggests that previous failures to obtain matching may be due to factors such as an insufficient length of exposure to each schedule or to the pigeons' repeated exposure to different concurrent schedules. 相似文献
905.
Pigeons' keypecks were reinforced with grain on the average of once per minute by schedules that maintained low response rates and by schedules that maintained high response rates. During these schedules, a fixed-duration conditioned stimulus (CS) ranging from 7.5 to 120 sec in duration across conditions terminated with response-independent food. Response rates during the CS were inversely related to CS duration. The rates and the temporal patterns of responding during the shortest CS were similar whether the ongoing schedule maintained high response rates or low response rates. As CS duration increased, the rate and pattern of responding during the CS converged on the rate and pattern of responding maintained by the baseline schedule. These data indicate that changes in responding during stimuli that signal response-independent reinforcement are not homogeneous throughout the CS; that response measures, such as “suppression ratios”, which presume homogeneity may mislead us; and that conditioned suppression and conditioned enhancement may be better talked about in terms of species-specific approach and avoidance than in terms of emotional states. 相似文献
906.
Ray Blanchard 《Learning and motivation》1977,8(4):569-580
Five pigeons were run on a one-key discrete trials observing procedure. Trial onset was signaled by a white or yellow key light. Pecks in white or yellow intermittently produced S+ and S−, green and red key lights that signaled whether the trial would end with response-independent grain reinforcement or nonreinforcement. In the Redundant conditions, white and yellow were correlated with trial outcome, making S+ and S− redundant. In the Informative condition, white and yellow were uncorrelated with trial outcome, so that S+ and S− provided new information. During the Informative condition, all birds responded in the formerly positive, now uncorrelated color at higher rates than they did during the preceding or succeeding Redundant conditions, in which that same color was positively correlated with primary reinforcement. This result confirmed the prediction that an animal will observe at higher rates in the absence of reinforcement-correlated cues than in their presence. 相似文献
907.
A new methodology extends the study of serial pattern learning to nonhuman organisms by constructing patterns using elements that are both familiar and motivationally meaningful to animals. Two experiments examine the ability of rats to anticipate various quantities of food as measured by running times in a runway when the quantities occur in a serial order. In Experiment 1, a serial monotonic pattern (14-7-3-1-0 food pellets) produced more rapid learning and more accurate anticipation of the various quantities (“tracking”) than a serial nonmonotonic pattern (14-1-3-7-0 food pellets), particularly with respect to the final 0-pellet element. In Experiment 2, the same monotonic pattern generated faster learning and more accurate anticipation of pattern elements than a weakly monotonic pattern (14-5-5-1-0 pellets). Associative explanations including simple excitatory or inhibitory effects, temporal anticipation, reinforcement contrast, and the number and discriminability of pairwise associations are not adequate to account for the data. Rather, the formally defined structural complexity of each pattern adequately predicts its relative difficulty. 相似文献
908.
Rats received Pavlovian aversive (shock) conditioning in which white noise was established for independent groups as a CS+, CSo, or CS−. Then, in an easy (light-dark) T-maze discrimination, the CS was presented either immediately following choice (Locus 1) or at the food cup in the goal (Locus 3), contingent upon either a food-reinforced (right) or nonreinforced (wrong) response. When presented at Locus 3, the CS+ facilitated and the CS− retarded learning for CS/right subjects, with these effects being exactly reversed but somewhat less pronounced for CS/wrong subjects. However, when the CS was presented at Locus 1, the CS+ and CS− effects for both response contingencies were attenuated. These findings oppose an interpretation of the CS's function as a general cue or transformed signal for the presence or absence of the new appetitive reinforcer and argue instead for across-reinforcement blocking effects: By signaling in the presence of food reinforcement an outcome (safety or shock) which is consonant with or discrepant from the “good” outcome obtained, the CS− blocks (retards) and the CS+ counterblocks (enhances) the association of food reinforcement and the SD; conversely, in the presence of nonreinforcement (a “bad” outcome), the CS− counterblocks and the CS+ blocks inhibitory conditioning to the SΔ. As in Kamin's (1968) original research, such effects are attenuated when the CS is presented early in the compound, distal to the reinforcer. 相似文献
909.
Alexis C. Collier 《Learning and motivation》1977,8(2):159-170
Three groups of rats were exposed to pairs of three different contingencies on two sides of a shuttlebox. One signaled contingency provided 10-min danger and safety cues plus an additional 10-sec cue immediately preceeding shock (P-S), another signaled contingency provided 10-min danger and safety cues but random 10-sec cues with respect to shock (R-S), and an unsignaled contingency provided no safety period, but only a 20-min danger period during which shock could occur (NS). Signaled P-S and R-S contingencies were preferred in a choice test to the unsignaled NS contingency, and P-S was preferred to R-S. Independent tests of the fear-eliciting properties of the cues made in an off-baseline test of suppression of ongoing exploration indicated more freezing (fear) to the 10-sec cue in rats experiencing the P-S contingency. The results were interpreted as indicating a preference for cues providing more precise information about the temporal location of shock even when those cues were fear-eliciting. 相似文献
910.
Donald M. Wilkie 《Learning and motivation》1977,8(2):182-193
Pigeons' key pecking in the presence of one stimulus (S1) was reinforced according to a response-dependent variable-interval schedule. Pecking rate during S1 increased (behavioral contrast) when a second stimulus (S2) [associated with either a response-dependent fixed-interval schedule (Experiment I) or a response-independent reinforcement schedule in which reinforcement availability was signaled by visual (Experiment II) or temporal (Experiment III) stimuli] alternated with S1. These experiments suggest that a discriminable, signaled decrease in local reinforcement rate during S2 is an antecedent of the behavioral contrast response rate increases during S1. 相似文献