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91.
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   
92.
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   
93.
94.
Two levels of confinement duration (5 or 60 sec) in either startbox or goalbox were factorially combined with presence or absence of shock during extinction of a runway escape response in a self-punitive paradigm under a spaced-trials procedure. All groups were equated for amount and temporal spacing of handling before and after each trial. Shocked rats were more resistant to extinction than nonshocked rats only when startbox confinement was short. When startbox confinement was long, shock facilitated extinction. Long goalbox confinement enhanced running speed for shocked rats, but only in the presence of shock. It was suggested that duration of startbox confinement affects strength of conditioned fear, with long confinement leading to its extinction.  相似文献   
95.
The associations formed in the components of a multiple schedule can be classified as (1) stimulus-response (S-R) associations and (2) stimulus-reinforcer (S-SR) associations. The present experiments sought to determine the individual contribution of these S-R and S-SR associations to stimulus control by manipulating them independently. Responses postponed shocks by 25 sec in the presence of a tone alone and a light alone in all experiments. The contingencies programmed in the absence of both tone and light established a reference for the S-R and S-SR associations in tone and in light. All four possible combinations of signalling response increase or decrease together with incentive increase or decrease were studied. Although the influence of the contingencies operating in the absence of tone and light was difficult to detect from response rates in tone or light, presenting tone and light together revealed clear effects. Response rates in tone and light together relative to those in either alone depended upon the contingency operating in the absence of tone and light. Stimulus-response and stimulus-reinforcer associations appeared to counteract each other when in opposition and combine together to enhance each other when in agreement. This suggested that the associations of a stimulus to response and to incentive combine algebraically in determining stimulus control. An algebraic analysis in terms of the S-R and S-SR associations conditioned to the stimulus elements comprising the training and test stimuli accounted for the observed patterns of data.  相似文献   
96.
The effect of sample stimulus presentation time on long-delay matching in highly practiced pigeons was investigated. The birds were found capable of above chance matching performance at a delay of 60 sec provided the sample stimulus was presented for 4 sec or longer. Matching accuracy increased as a negatively accelerated function of sample stimulus presentation time and decreased as a negatively accelerated function of time since the termination of the sample. The rate of forgetting was found to be independent of sample stimulus presentation time. The data were inconsistent with a temporal discrimination interpretation of the effect of presentation time on delayed matching. The data were interpreted as supporting a simple trace strength and decay model of pigeon delayed matching.  相似文献   
97.
In contrast to a recent finding (Macdonald, G. E., & De Toledo, L. Learning and Motivation, 1974, 5, 288–298.) the results of three experiments investigating various partial reinforcement (PRF) manipulations under conditions of thirst motivation demonstrated strong similarity to analogous manipulations involving food reward. Specifically, for animals receiving water reinforcement, PRF was shown to generate greater resistance to extinction than continuous reinforcement (Expt 1 & 3), the schedule of reinforcement was shown to interact with level of acquisition (Expt 1 and 2), and the magnitude of the partial reinforcement extinction effect was shown to be a function of reward magnitude (Expt 3). These results provide strong evidence that mechanisms which operate in partial reinforcement situations are highly similar, regardless of the type of appetitive reinforcement.  相似文献   
98.
McCauley, Stitt, Woods and Lipton's finding that groups were more conservative than individuals when betting at a race track has been criticized on statistical and methodological grounds. The present study which does not suffer the shortcomings for which McCauley et al. were legitimately criticized does, nonetheless, sustain their general results and conclusions. Groups were significantly more cautious than individuals when wagering $2.00 on a horse race.  相似文献   
99.
100.
Charles S. Peirce believed that his pragmatic philosophy could reconcile religion and science and that this reconciliation involves a religious ethics creating a real community with the cosmos and God. After some rival pragmatic approaches to God and religious belief inconsistent with Peirce's philosophy are set aside, his metaphysical plan for a reconciliation of religion and science is outlined. A panentheistic God makes the best match with his desired conclusions from the Neglected Argument for the reality of God, and this God is also capable of fulfilling the pragmatic role demanded by Peirce's ethical expectations for the intelligent functioning of religion. The discussion proceeds to an elaboration of the aesthetic, metaphysical, and ethical elements of Peirce's philosophical system, which indicate why Peirce's religious ethics is best categorized as akin to Stoicism, with some Christian elements. For Peirce, religious ethics proceeds from the (potentially universal) agapic community's cooperation with God's loving creativity of the universe.  相似文献   
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