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991.
Improvements in visual acuity following vision training were evaluated for an 1112-yr-old myopic male. Initial increases in the distance at which the S could discriminate letters were found. However, performance began to deteriorate as training progressed. A negative-reinforcement procedure was employed in order to rule out motivational factors potentially related to this decreased performance. Using a changing criterion within an ABCBC reversal design, the distance at which the S correctly discriminated letters increased by more than 412 times and was clearly related to the reinforcement procedure.  相似文献   
992.
Macklin R 《Synthese》1983,57(2):205-224
Psychiatrists are frequently called upon to make assessments of the rationality or irrationality of persons for a variety of medical-legal purposes. A key category is that of evaluations of a patient's capacity to grant informed consent for a medical procedure. A diagnosis of mental illness is neither a necessary nor a sufficient condition for a finding of incompetence. The notion of competency to grant consent, which is a mixed psychiatric-legal concept, shares some features with philosophical conceptions of rationality, but differs from them in a number of important respects. This article describes the actual practice of psychiatrists when making such judgments, along with the standards of competency they employ. A comparison is made between those notions of competency and predominant philosophical conceptions of rationality.  相似文献   
993.
Two experiments show that the spelling of a nonword that is heard (i.e., /prein/) is influenced by the spelling of a word that is heard earlier (i.e., “brain” > prain and “crane” > prane). This is a robust effect and inspection of the pattern of results suggests that, under these conditions, both words and nonwords are lexically analyzed. A patient with an aquired reading disorder characterized as surface dyslexia was unaffected by such lexical influences in his spelling of nonwords. Moreover, his spelling suggested a defective ability to generate phonemically acceptable spellings of nonwords. Taken together with other reports of neurologically caused spelling impairments these results suggest that skill at assigning letters to sounds never becomes independent of lexical skill in adult readers. An analogical, lexically based parsing system for the reading and spelling of new (nonwords, as suggested by Marcel (1980) appears to be the best fit to these data.  相似文献   
994.
Rats ranging from 8–21 days of age were inoculated in the right cerebral hemisphere with St Louis encephalitis virus, Japanese B encephalitis virus, Murray Valley encephalitis virus. Mumps virus however, was injected at age one day. When very young rats were injected with these viral preparations, fatal encephalitis usually developed. Rats injected at ages of more than two weeks showed little or no clinical signs of infection. When inoculated at ages between these extremes, clinical disease developed in most rats but many survived. Physically most of these surviving animals appeared to be normal, but when tested at maturity in a rather complex maze, they showed a marked reduction in learning ability. Tilting-cage-type activity measurements taken overnight with the Murray Valley encephalitis group also indicated that most of the postinfectious rats were hyperactive. These data imply that such a laboratory model might be related to similar hyperactivity and learning disabilities seen in certain types of minimally brain damaged children. A viral-sex interaction often seen in earlier studies is also noted in our animals injected at younger ages.  相似文献   
995.
996.
This experiment supplements a recetlf study of the effects of an interpolated weight upon memory for a standard (Parducci, Marshall, & Degner, 1966). The earlier data suggested that the stimulus-averaging approach as represented by the theory of adaptation level should be modified to incorporate the principle that Ss use alternative categories with equal frequency. The present data support this modification by demonstrating that even when the stimulus mean is held constant, judgments are affected by the relative frequencies of the comparison stimuli.  相似文献   
997.
This study outlines a simplified operant conditioning procedure for investigating discrimination based on response-produced stimuli. The method, using concurrent schedules of reinforcement, greatly reduced the complexity of the procedures and the number of training sessions necessitated by a recently offered alternative technique. Calculations of Weber’s Constant for discrimination between response-produced stimuli are presented and the relevance for learning theory of empirical studies concerning response-produced stimuli is indicated.  相似文献   
998.
999.
A comparison was made between the Bales and the Carter-Haythorn-Meirowitz-Lanzetta methods of systematic observation. The comparison was limited to the categorizing of verbal behaviour. It was found that there are several deficiencies in the latter method with respect to the classes used, and that satisfactory observer reliability could not be obtained. By using the Bales method, on the other hand, fairly high total observer reliabilities were achieved, and even the category reliabilities in various classes turned out to be satisfactory, provided the category frequencies were large enough.  相似文献   
1000.
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