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921.
Seven contingency theories of classical and instrumental conditioning were defined in relation to the contingency matrix and to six separate probabilities which can be derived from this matrix. These theories were compared on the basis of formal similarities and differences, and were judged against three separate empirical variables which have been discussed in the contingency literature: the duration of the intertrial interval, partial reinforcement, and negative contingencies between the two events of conditioning. All previous theories had some difficulty predicting the effects of one or more of these variables upon animal conditioning. Also, some formulas make the unusual prediction that there will be less conditioning when there is more than one conditioning trial. The paper concluded with an extensive discussion of the problems that are created by conditioning events with temporal extension; events which are then categorized by a contingency matrix which has no temporal character. Some possible solutions to the problems were discussed.  相似文献   
922.
Processing times for English and Chinese words   总被引:1,自引:0,他引:1  
  相似文献   
923.
924.
925.
926.
This study was designed to determine the feasibility of using lingual vibrotactile stimulation to elicit an averaged evoked response and to investigate the effects of two supra-threshold intensity levels of lingual vibrotactile stimulation on the electro-cortical activity of the brain. The evoked responses were analyzed according to the amplitude of N1-P2 (in microvolts). Analysis indicates that the tongue can successfully be used as a stimulus site in the elicitation of an evoked response. The amplitudes of the evoked response elicited by 2 micrometers sensation level and 5 micrometers sensation level on the tongue are essentially the same. The relative difference between these levels is not sufficient to produce significant differences in the amplitudes of their respective evoked responses.  相似文献   
927.
The model of assessment in educational and vocational counseling is the “matching model.” It inhibits developmental counseling. A stage-theory model is proposed instead and is case illustrated.  相似文献   
928.
This paper presents a new neuropsychological screening battery for psychiatric patients. It takes 1.5 to 2 hr to administer and briefly assesses general level of performance, memory, language skills, attention, and spatial-constructional abilities. Scoring and profiling are computerized. Initial validation based on discriminant analysis of a group of brain-damaged and non-brain-damaged psychiatric patients yielded a diagnostic accuracy level of 84.51%. Cross-validation on a different population led to a substantial attrition of classificatory accuracy, but cross-validation based on a comparison between two samples drawn from a homogeneous population yielded substantially less attrition. It was concluded that while the battery discriminates accurately in a homogeneous population, it is necessary to develop separate norms for populations varying in level of impairment.  相似文献   
929.
930.
Glutamate is believed to be quantitatively the most outstanding of the excitatory transmitters in the CNS. Certain conformationally related analogues, e. g. kainate, N-methyl-D-aspartate, ibotenate, and homocysteate, act as glutamate agonists. The local or systemic administration of these "excitotoxic" compounds induces epileptiform activity pointing out new and deeper insights into the epileptic process. Additionally, the glutamate transmitter hypothesis is expected to give a chance of a causal comprehension for choreatic processes as well as for the mode of action of anticonvulsant and antispastic agents.  相似文献   
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