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151.
James R. Stagray David Downs Ronald K. Sommers 《Journal of psycholinguistic research》1992,21(6):511-524
We measured subjective-tone identification thresholds evoked by acoustically filtered complex tones and compared them to Mandarin-Chinese tone-phoneme identification thresholds previously measured under the same filtering conditions. Tone phonemes were identified at intensities below subjective-tone identification thresholds, suggesting subjective tone is not necessary for tone-phoneme identification. Lower subjective-tone thresholds evoked by resolved harmonics rather than unresolved harmonics were consistent with pattern recognition theories of pitch perception.The authors thank Donald Gans and Richard Klich for all their help. 相似文献
152.
M C Rodriguez-Perez F de Vicente-Perez G Gomez-Jarabo Garcia 《Behavioral and neural biology》1992,58(3):165-170
The use of neurological tests in various states of undernutrition has confirmed the presence of delays in reflex ontogeny. Glucocorticoid administration in conditions of normal nutrition produces diminished growth and alterations in brain development similar to those observed in malnutrition, but there is not enough evidence about its effect on reflex development. In addition, some facts lead us to think that the use of permissive doses of these hormones during gestation could alleviate some of the effects of protein malnutrition on the development of pups. In the present study the ages at which certain reflexes appeared in the offspring of Wistar rats (Rattus norvegicus) fed a 20% (N) or 10% (M) protein diet from a week before conception to the end of lactation were observed. Each dietary group was subdivided into two: mothers receiving a daily injection during gestation either of a 0.9% NaCl (S) solution or of a 0.5 mg/100 g weight hydrocortisone acetate (C) solution. Results showed that the NS group of pups generally presented earlier ages of appearance of the variables under study than the remaining groups. Pups of the NC group presented delays in the age of appearance of reflexes. Finally, protein malnutrition delayed the appearance of reflexes and this effect seemed to be attenuated by treatment with hydrocortisone. Thus, hydrocortisone administration in protein malnutrition conditions seems to be beneficial although the results are harmful when administered under normal nutritional conditions. 相似文献
153.
Fifteen rats performed in a standard radial-arm maze task (Experiment 1) and in a modified task with a set of forced choices and a 15-min retention interval prior to completion of the maze (Experiment 2). In addition to the standard measure of choice in the radial-arm maze, orientation toward arms was measured and considered to constitute go-no-go "microchoice" decisions. Rats investigated but rejected many arms. A model of choice was developed in which it was assumed that choice decisions about arms were made independently and that microchoices were not selectively guided toward baited arms. The model performed nearly as well as the rats. These results place important limitations on the theory that choice behavior in the radial-arm maze is guided by a cognitive map. 相似文献
154.
This article describes a study conducted to identify the range of potential influences that a computer-assisted careers guidance system (PROSPECT (HE)) had on the functioning of organisations (careers services in higher education). Data from six institutions indicated that use of PROSPECT (HE) was associated with important and varied change within the organisations. It appears that when a careers service seeks opportunities for change, CACG systems can be an important catalyst for change in two respects: by providing a focal point for achieving previously established goals; or, as a consequence of system use, by making staff aware of the potential for new organisational goals. 相似文献
155.
James E. Gruber 《Sex roles》1992,26(11-12):447-464
Most of the research conducted on sexual harassment over the last decade and a half has used categories that are neither mutually exclusive nor exhaustive. This has created problems for researchers: it is difficult to compare results from one study to another, harassment types that have scholarly and legal-policy relevance are omitted, and the ability of researchers to inform legal and policy decisions is diminished as a result of these problems. A comprehensive categorization of harassment types that addresses these methodological problems is presented. Specifically, 11 specific types of harassment—4 types of Verbal Requests, 3 Verbal Remarks, and 4 Nonverbal Displays—are presented with examples from research and legal literatures. Recommendations for reconceptualizing research definitions of harassment as well as for diversifying the methodological approaches to the topic are made. 相似文献
156.
Human analog tests of object permanence were administered to various breeds of adult dogs (Canis familiaris). Experiment 1 showed that the performance of terriers, sporting, and working dogs did not differ. Dogs succeeded in solving invisible displacement problems, but performance was lower than in visible displacement tests. Familiarity with the task had some influence because invisible displacement tests were more successful if they were preceded by visible displacement tests. In Experiment 2, odor cues from the target object and the hiding screens were available or were masked. Results confirmed that success was lower in invisible than in visible displacement tests and that these problems were solved on the basis of representation of visual information rather than on the basis of olfactory cues or of local rule learning. Dogs are compared with other species that display Stage 6 object permanence. 相似文献
157.
158.
Elders exposed to either progressive or imaginal relaxation procedures reported significant relaxation effects and showed improvement on measures of personal functioning. The results of the Physical Assessment Scale of the Relaxation Inventory indicated that relaxation responses were acquired within and across sessions. Large, consistent changes in relaxation occurred in all 4 sessions. The Symptom Checklist-90-R, which measures self-reported personal adjustment, showed significant positive changes following relaxation training and at 1-month follow-up. Elders who imagined muscle tension release profited as much as those engaged in actual muscle tension-release activities. This finding is of importance for older adults who may experience physical limitations that contraindicate muscle-tension-release procedures. 相似文献
159.
Adult age differences were explored on 3 short tests of the ability to generate and manipulate mental images. Age-related decrements were found in all 3 tests and were especially marked on the Clock Test. The tests are all reliable, as shown by test-retest reliability coefficients. Correlations also revealed that the Brooks Letter Test and the East-West Test appear to tap one common underlying ability, whereas the Clock Test measured a somewhat different ability. The East-West and Clock tests, in particular, may provide rapid and easily administered assessments of age-related changes in aspects of mental imagery. 相似文献
160.