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891.
A simple input and output circuit is described that allows users to sense contact closures and to drive relays from a Digital Equipment Corporation LSI-11 DRV 11 parallel interface board or a signal-compatible equivalent.  相似文献   
892.
893.
Two experiments investigated the capacity of a nominal CS to overshadow background stimuli. Rats received CS-shock pairings in one compartment of a double compartment apparatus. After training the shock compartment was represented, but in the absence of both the CS and shock. Overshadowing was then assessed by measuring rats' latency to enter this compartment. If rats readily entered the shock compartment this indicated that the background cues in that compartment had acquired little or no associative strength during training, and overshadowing was therefore inferred. If however rats avoided the shock compartment, then this indicated that the background stimuli must have become aversive during training, and overshadowing could not then be inferred. In both experiments it was found that the capacity of a CS to overshadow background stimuli was directly related to the amount of training given. The experiments also showed that this capacity is inversely related to shock intensity. The results are discussed in terms of Rescorla and Wagner's (1972) model of conditioning.  相似文献   
894.
The relationship between sleep and learning processes is analysed in a sample of schizophrenic patients, starting from more recent hypotheses about the function of REM sleep in learning and memory processes. This is done by means of two experiments: in the first AA. evaluate the possibility to elicit a simple motor conditional reflex acquired during daytime in different sleep stages. With the second experiment daytime learning performances are evaluated with and without a reinforcement administered during REM sleep. Results for the first experiment underline a qualitative difference between REM and nREM sleep in a reflexological perspective. In nREM sleep the conditional response is better maintained than in REM sleep. The second experiment confirms the possibility to improve daytime learning performances after an additional presentation of learning material in REM. The joint study of sleep abnormalities and learning and cognitive impairment in schizophrenic patients is finally suggested.  相似文献   
895.
A simple device capable of eliciting and detecting earthworm locomotor activity is described and its use outlined. Movement is recorded as an animal crawls in a spoked, revolving wheel. The wheel permits peristaltic crawling, yet restricts the type and timing of other movements. As a result, records of activity differentiate the rate and patterning of peristaltic crawling from changes in bodily position.  相似文献   
896.
A rapid inexpensive technique for changing from intravenous drug self-administration (DSA) to liquid reinforcement is described. Utilizing a standard peristaltic-type infusion pump typically used in DSA experiments and a specially designed drinking cup, the changeover from intravenous DSA to liquid reinforcement can be accomplished in a few minutes at a cost of less than $10.  相似文献   
897.
898.
Memory for music     
Subjects created imaginal interpretations of classical music passages in accordance with themes which were either concrete and comprehensible or abstract and difficult to comprehend. Recognition memory for the musical passages was found to be superior in the former condition. The results support the hypothesis that meaningful interpretation of stimulus material is a major determinant of memory accuracy. The implications of the results for comparisons of music and language are also discussed.  相似文献   
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