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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
987.
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
988.
Tenacious goal pursuit and flexible goal adjustment: explication and age-related analysis of assimilative and accommodative strategies of coping 总被引:6,自引:0,他引:6
Crises and critical life transitions activate 2 distinct but complementary modes of coping, (a) transforming developmental circumstances in accordance with personal preferences (assimilative tendency) and (b) adjusting personal preferences to situational constraints (accommodative tendency). Assimilative and accommodative tendencies were measured by a questionnaire comprising 2 independent scales (Tenacious Goal Pursuit and Flexible Goal Adjustment). Both scales predict high life satisfaction and low depression and are positively related to generalized internal control beliefs. The scales evinced an opposite relation to age: Cross-sectional analyses on a sample of 890 Ss in the age range from 34 to 63 years revealed a gradual shift from an assimilative to an accommodative mode of coping. Implications for theories of depression and successful aging are discussed. 相似文献
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990.
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