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231.
This brief note has two parts. First, it presents an analysis of the ability of English agrammatic patients to assign the thematic roles of agent, instrument, theme, and locative to noun phrases in active and passive sentences and prepositional phrases. Data regarding this ability have been presented by Schwartz, Saffran, and Marin (Brain and Language, 10, 149-262 (1980) regarding comprehension, and by Saffran, Schwartz, and Marin (Brain and Language, 10, 263-280 (1980) regarding production. These authors claim their data show that English agrammatic aphasics do not map "word order" onto thematic information. However, a very simple set of principles accounts for all their results, including results which are discrepant in their treatment, but requires that English agrammatics assign thematic roles to NPs in part by virtue of the position of an NP in a sentence or a phrase. In the second part of this note, several issues raised by this re-analysis are briefly discussed.  相似文献   
232.
The Job Attitude Scale was administered to majors and captains and to upper-middle managers and lower-middle managers of industrial organizations. No significant differences in general intrinsic orientation were found between the majors and the upper-middle managers, or between the captains and the lower-middle managers. The majors and the upper-middle managers were significantly more intrinsically oriented than the captains and the lower-middle managers. The results also showed that the military samples were significantly more concerned with advancement, security, status, and family needs-salarywise-than the civilian samples, while the two civilian groups were significantly more concerned with achievement, supervision, and relations with subordinates than the two military groups. The results were discussed in view of job environment and job level.  相似文献   
233.
The influence of the presence and novelty of an adult stranger on the reactions of 12-mo-old infants was investigated. Subjects were placed near their mothers in a room containing a new toy and either the same, a different, or no adult stranger for 8 4-min trials. Results indicated that the Same-Adult Group spent more time near the adult, less time near and touching their mothers, and more time near and touching the toys than the Different-Adult Group. These trends emerged as the trials progressed, and evidenced the Same-Adult Group's growing familiarity with the adult. The No-Adult Group spent less time near or touching their mothers and more time near or touching the toys than the Different-Adult Group, but did not differ from the Same-Adult Group on these responses. The findings suggest that fearful or cautious reactions to adult strangers disappear rapidly as the adult becomes familiar and point to the value of studying the process whereby the infant becomes familiar with new people.  相似文献   
234.
Three experiments investigated the importance of operant-reinforcer distance as a factor affecting continuous reinforcement (CRF) and fixed-ratio (FR) performance in mice, with nest material and food as reinforcers. In Experiment 1, nest material (paper strips) was presented on a series of FR schedules of increasing size, with the operandum located as close as possible to the reinforcer dispenser. Subjects compensated for increases in FR size by proportionately increasing their response output, but ratio strain occurred at low FR values. In Experiment 2, response rate was found to be inversely related to operant-reinforcer distance on a CRF schedule with nest material as reinforcer. In Experiment 3, food was presented on a series of FR schedules at two levels of deprivation, and with three operant-reinforcer distances. Operant-reinforcer distance was found to affect CRF response rate, degree of compensation for increases in FR size, and occurrence of ratio strain, but only when deprivation level was low. The results support the view that nest material and food share fundamentally similar reinforcing properties, but that nest material is a weaker reinforcer under normal test conditions.  相似文献   
235.
In the acquisition phase, pigeons learned to peck at a changeover key to shorten the duration of S? but not of S+ presented on the food key in a discrimination problem. In the transfer phase, the significance of S+ and S? was changed through extinction of both, equal reinforcement, or discrimination reversal, while the changeover key was not available. Transfer tests then showed appropriate modification of the changeover response. Similar transfer was demonstrated across orthogonal stimulus dimensions. Further analytic studies showed that this transfer of the changeover response did not depend upon mediation due to differential response rates to the food key. This research strategy enriches the study of the “second learning process” by providing an indicator of stimulus control in all phases of the procedure. Direct transfer between different problems also indicates that discriminative stimuli, although physically dissimilar, have the same “psychological value” for the subject.  相似文献   
236.
To determine whether the distraction effect associated with material rewards in discrimination learning can account for the superior performance of reward groups in probability learning, the performance of 144 school children (preschool, second, and fifth grades) on a two-choice successive discrimination task was compared under three reinforcement conditions (material reward, marker, and knowledge of results). The two events in the task had different frequencies of occurrence, as in probability learning, yet they appeared in a constant order to make 100% payoff possible. The subjects in the reward and marker groups learned the task more slowly, and the nonlearners among them used stereotyped alternation patterns to a greater degree than subjects in the knowledge-of-results condition. These findings suggest that a distracting effect of material reward is present in probability learning and may explain the superior performance of reward groups typically found in probability learning studies.  相似文献   
237.
Four- to seven-year-old children observed a simple physical effect which could be attributed to either a consistent but noncontiguous covariate or a contiguous but inconsistent covariate. When there was a physical rationale for the temporal delay between covariate and effect, children attributed the effect to the consistent but noncontiguous covariate. In the absence of such a rationale, they attributed the effect to the contiguous but inconsistent covariate. It was concluded that neither consistent covariation nor strict temporal contiguity were essential aspects of causal inference for these children.  相似文献   
238.
Spatial representation by 72 blind and blindfolded sighted children between the ages of 6 and 11 was tested in two experiments by mental rotation of a raised line under conditions of clockwise varied directions.Experiment 1 showed that the two groups were well matched on tactual recognition and scored equally badly on matching displays to their own mentally rotated position.Experiment 2 found the sighted superior in recall tests. There was a highly significant interaction between sighted status and degree of rotation. Degree of rotation affected only the blind. Their scores were significantly lower for rotating to oblique and to the far orthogonal directions than to near orthogonal test positions. On near orthogonals the blind did not differ from the sighted.Age was a main effect, but it did not interact with any other variable. Older blind children whose visual experience dated from before the age of 6 were superior to congenitally blind subjects, but not differentially more so on oblique directions.The results were discussed in relation to hypotheses about the nature of spatial representation and strategies by children whose prior experience derived from vision or from touch and movement.  相似文献   
239.
240.
A study was designed to assess the contributions of the factors of sex and familial history to cerebral dominance, where cerebral dominance was inferred from laterality on a dichotic listening task. The 144 subjects were selected from a larger sample on the basis of handedness, sex, and familial history of sinistrality, and tested on a task involving the dichotic presentation of CV syllables. Analysis of the data indicated that in female subjects, the presence of familial sinistrality increased the likelihood that they present atypical left-ear superiorities, while in males the converse was the case. Moreover, there was a significant sex difference overall, such that males were more clearly lateralized than females. A review of other dichotic listening studies provided support for the reliability of this sex difference for dichotic tasks using verbal material. A review of the clinical literature indicated that the hypothesis of a sex difference is at least tenable and merits further investigation. However, the possibility that there is a sex difference in the cognitive strategy used in dichotic listening cannot be ruled out.  相似文献   
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