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891.
Young, severely maladaptive autistic children with some speech competence were compared to normally developing 3-year-old children of lower and middle class and 5-year-olds of lower class on negation tasks. All subjects were shown 12 sets of cards depicting negative contrasts designed to elicit semantic categories of nonexistence, denial, and rejection and were tested for production, imitation, and comprehension. Syntactic and semantic analysis revealed that autistic children were superior imitators and poor producers but showed skills in comprehension comparable to a 4-year-old's level of functioning. While retarded in some functions, the experimental group produced syntactic structures that were more rigid, suggesting the significantly greater use of imitation as a major strategy in linguistic coding.This work was done at the NYU-Bellevue Medical Center with partial support by NIMH Grant No. MH 07331 to R. K.  相似文献   
892.
893.
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   
894.
This paper presents a brief history of the use of internal computer networks, an introduction to networking concepts and topology, and suggestions regarding a possible system for use in a psychology laboratory. Considerations about the design and use of a microcomputer network are discussed.  相似文献   
895.
896.
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   
897.
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   
898.
In goldfish the heart rate orienting response to periodic photic stimuli was measured by a specially designed computer that also regulated the intensity of the stimuli to maintain the response. When ethanol was administered, the fish then exhibited orienting responses to less intense stimuli; this increased excitability was maintained for the duration of all tests(i.e., a maximum of 26 hours). There also seemed to be a residual increase of excitability lasting as long as 7 days after the ethanol was administered.  相似文献   
899.
The Yale experimental programming system is described. This system consists of user-callable subroutines and a set of modifications to the UNIX operating system which support the development and execution of real-time psychology experiments. The interactions between a timesharing operating system and the provision of real-time facilities for experiments are discussed.  相似文献   
900.
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   
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