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961.
962.
Rats in a two-lever situation were exposed to alternating periods of intermittent reinforcement and extinction. Extinction periods were either unsignalled or were signalled by a response-produced stimulus. The signal was sometimes a stimulus paired with food delivery in the reinforcement periods and sometimes a stimulus that occurred only in extinction periods. Both kinds of signal accelerated extinction relative to the unsignalled condition. When the signal was the stimulus paired with food in reinforcement periods, the rats tended to prefer the lever that gave that signal even though the signal accelerated extinction. There was no comparable effect for the stimulus that occurred only in extinction periods; when this signal was contingent on only one of the two levers, the rats either avoided it (Experiment 3) or were indifferent (Experiment 4). It is concluded that a stimulus can be a “secondary reinforcer” as measured by preference, even though it decreases resistance to extinction; the implications are discussed with reference to formal theories of choice behavior.  相似文献   
963.
Fifty-seven aphasic patients' comprehension of five sentence forms which express the temporal order of events has been investigated. Three major patterns of errors of temporal relations have emerged. The dominant pattern is exhibited by patients making errors on Before's but not on After's. The second and third patterns comprise a fewer number of patients making errors on After's but not on Before's and those making errors on both Before's and After's, respectively. It has been shown that different syndromes of aphasia are equally distributed among these three patterns. In the follow-up study of several patients, fluctuating courses of recovery in which comprehension of before and after alternately increases and decreases have been observed. These results are discussed in connection with a possible account of the acquisition of before and after in Japanese.  相似文献   
964.
965.
A series of experiments was performed to determine how the duration of a word spoken in a sentence is influenced by: (1) the grammatical category to which it belongs, and (2) the position of the word in a constituent. Experiment I contained Noun-Verb homophones (e.g. “I saw the coach…” — noun; “I saw him coach…” — verb), in sentences matched for phonetic environment and stress pattern. Results support the notion that Nouns are longer than Verbs in typical sentences. Experiment II, however, demonstrated that the duration of Noun-Verb homophones in matched clause-final position is approximately equal. Experiment III contained transitive and intransitive Verbs in matched sentences. The results of Experiments II and III provided support for a lengthening account based on constituent-final position, while ruling out an account based on a debatable deletion site. Results of Experiment IV generalized the account of constituent-final lengthening for Nouns and Verbs to additional major categories, by comparing the duration of the phrase-initial Adjective two with the phrase-final Adverb too. Finally, Experiment V tested the distinction between minor and major categories. Results demonstrated that the Preposition to is shorter than the Adjective two by approximately 50 percent. Taken in sum, these findings indicate that it is sufficient to make a binary distinction between major and minor categories for purposes of a theory of speech timing and speech synthesis. Durational effects traditionally ascribed to differences within the class of major categories can be accounted for solely in terms of constituent boundaries, already required in the theory to account for three other classes of phenomena.  相似文献   
966.
Ninety-six children copied simple line drawings of perspective views of cubes and similar designs unlikely to be seen as representing objects. The views of cubes were copied much less accurately than the non-object patterns, and the errors made in copying the cubes involved replacement of properties specific to the single perspective view by properties more appropriate to the object itself. Some copies were drawn with the child continually looking at the model and unable to see his own copy, others were drawn in the normal way. Copies made in the former way were more accurate, but even under these conditions cubes were copied less accurately than the non-object patterns. The disadvantage of object pictures, as far as literal copying accuracy is concerned, was still present at 9 1/2 years of age, but was less than at 7 1/2. Two possible explanations are discussed. One is in terms of computational complexity, the other in terms of graphic motor schema. On the basis of the drawings obtained a few suggestions are made about the content and development of the data-structures for cubes.  相似文献   
967.
968.
One-hundred-and-sixty adolescents participated in two studies designed to investigate the relationship between IE and helping behavior as mediated by the perceived cause of another's need. In the first study, Ss were given the opportunity to help, either “indirectly” or “directly,” a supervisor who had been over- or underpaid in a prior similar task. Internals helped more in the “direct” help than the “indirect” help conditions but their helping behavior and their perceptions of their supervisors were not consistent. The perceptions of the externals were relatively consistent with their greater help of the “overpaid” supervisor. In study 2, the Ss were given additional information to increase the possibility of their making causal attributions as a function of the supervisor's prior fate. Once again, the external subjects' helping behavior reflected their perception of their supervisor's merit. The internal subjects exhibited relatively little helping behavior regardless of their supervisors' prior fate or perceived competence.  相似文献   
969.
Verbal utterances of 105 patients have been analyzed. Six groups of subjects were examined including patients with left dorsolateral frontal lesions, left orbitofrontal lesions, right frontal lobe lesions, posterior aphasics, posterior brain-damaged patients without aphasia, and a matched control group. Results indicate that the left frontal lobe is involved in organization of linguistic information. Its dorsolateral part seems to be concerned with forming the sequential pattern of an utterance, and the orbital part with the directed development of a narrative. It is conceivable that the right frontal lobe is important for the global, nonlinguistic organization of information to be uttered.  相似文献   
970.
In a recent article, H. D. Day, D. Marshall, B. Hamilton, and J. Christy (1983, Journal of Research in Personality, 17, 97–109) have reported on a series of simulation studies designed to investigate properties of various coefficients of behavior stability as applied to cross-situational data. The results of their research have prompted them to suggest precautions regarding the measurement of behavioral regularity with conventional indices of response consistency. A critical review of their paper reveals aspects of the data, procedures, and interpretations of Day et al. (1983) which undermine many of their conclusions. Notable problems include (a) inappropriate comparisons of internal consistency reliability coefficients based on nonparallel analyses, (b) anomalous data which may be due to errors of rounding or recording, and (c) the failure to recognize certain assumptions underlying reliability estimation. More importantly, it is shown that the investigation of Day et al. (1983) represents primarily an empirical verification of several measurement principles for which algebraic proofs are amply documented.  相似文献   
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