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If rats are overtrained on a visual discrimination they generally learn the reversal of the discrimination faster than non-overtrained rats. In position discriminations, however, this effect does not generally hold—indeed several investigators have found overtraining to retard position reversal. One of the important differences between the two types of problem seems to be the presence of irrelevant cues in visual discriminations, and their absence in position discriminations. It is suggested that a second important feature of position discriminations is that overtraining usually causes control of the maze running habit to be transferred from external to proprioceptive stimuli, and that successful reversal cannot normally occur until external control is re-established. In two experiments a study by Krechevsky and Honzik (1932) is repeated with certain modifications, with results that support this hypothesis; and a third experiment provides direct evidence of transfer to proprioceptive control in a T-maze. It is shown that this analysis will explain the apparently conflicting results of all recent position reversal experiments. 相似文献
795.
Facets of support related to well-being: quantitative social isolation and perceived family support in a sample of elderly women 总被引:4,自引:0,他引:4
The purpose of this study was to examine the independent and interactive relationships of measures of network embeddedness and perceived social support with mental and physical health measures from responses of a sample of 271 community-dwelling elderly women. Quantitative social isolation was measured as the co-occurrence of low network embeddedness with family and with friends. There was a threshold effect such that quantitatively isolated participants had poorer psychological well-being and functional health than did nonisolated participants. This effect was independent of perceived support levels. The pattern was different for perceived social support. Elderly women with low perceived family support had poorer psychological well-being regardless of perceived support from friends or network embeddedness. Implications are discussed for several unanswered questions in the social support literature, including possible interventions for the quantitatively isolated and for those with low levels of perceived support. 相似文献
796.
DANIEL K. LAPSLEY KENNETH G. RICE DAVID P. FitzGerald 《Journal of counseling and development : JCD》1990,68(5):561-565
We examined the concurrent relationship between late adolescent attachment to parents and peers and two broad indices of adolescent adaptation—personal and social identity and adjustment to college. Participants included 130 college freshmen and 123 upperclassmen. Although freshmen were disadvantaged relative to upperclassmen with respect to social and personal-emotional adjustment, there were no group differences on the attachment measures, on the measures of academic adjustment and goal commitment, and on the measure of social identity. Freshmen scored higher on personal identity than did upperclassmen. Women reported less alienation from peers, had more trust and better communication with peers, and had higher scores on personal and social idenitity than men. The attachment variables were significant predictors of personal and social identity. Pervasive relations were also found between attachment and adjustment to college, particularly for the upperclassmen sample. 相似文献
797.
ROBERT K. HEINRICH JOSEPH L. CORBINE KENNETH R. THOMAS 《Journal of counseling and development : JCD》1990,69(2):128-133
This article addresses the issues facing White counselors in providing services to Native Americans, whose values differ significantly from the dominant culture's. Native Americans have been consistently threatened with cultural assimilation. Previously published recommendations to counselors are reviewed and the relevance and possible uses of traditional Native American healing practices are discussed. One such practice, the vision quest, is described in detail. Counselors need to learn culturally relevant metaphors in order to promote healing and change and, in effect, must themselves undergo an acculturation process. 相似文献
798.
Previous training studies of fluid intellectual abilities have involved training on either figural relations or induction tasks. In the present study, young, middle-aged, and elderly adults were given training on another measure of fluid ability--Raven's Progressive Matrices. The training involved a strategy-modeling technique that lasted no more than a few minutes. The results indicated that (a) performance on the Raven decreased with increasing age, (b) training significantly improved performance, and (c) the effect of training did not differ as a function of the age or sex of the subjects. Thus, the results indicate that performance on the Raven can be significantly improved in a single, brief training session. 相似文献
799.
Systematic 24-hr behavioral observations of sleep and wakefulness in a skilled-care nursing facility
Sleep patterns of aged, infirm, demented, chronically institutionalized residents of a skilled-care nursing facility were studied. The purpose of this naturalistic study was to describe sleep and wakefulness (S/W) within the limits afforded by brief behavioral observations and to examine homeostasis and diurnal rhythmicity of S/W as a function of psychoactive drug intake. Observers noted S/W every 15 min, 24 hr a day for 10 days in 24 Ss. Results indicated substantial individual variation in daytime hours. Daily and weekly variation within Ss was minimal. Sleep was least likely near sunset. Ss on psychoactive drugs showed dampened diurnal variation in S/W rhythms. In Ss not on such drugs, there was a suggestion of homeostasis of S/W between sleep during the morning and evening hours. Results are discussed methodologically (viability of approach), theoretically (age-related change in sleep), and practically (potential treatments). 相似文献
800.
Teaching the Use of Cost-Benefit Reasoning in Everyday Life 总被引:1,自引:0,他引:1