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871.
The influence of contextual stimuli on the conditioning and performance of responding to a discrete stimulus was examined in the US preexposure paradigm using both context shift manipulations and a measure of context conditioning. Four groups of rats received both repeated exposure to an electric shock US in one context (Context 1), and repeated nonshocked exposure to a second context (Context 2). Two additional groups of rats received exposure to these contexts, but never received shock presentations. Rats exposed to shock learned to escape from the stimuli of Context 1, but did not escape from the stimuli provided by Context 2. Rats not exposed to shock failed to escape from either context. All rats then received a single CER conditioning session in which four pairings of a 3-min noise CS and shock US were presented. Half the rats received those CS-US pairings in the excitatory Context 1, while the remaining rats received those pairings in the neutral Context 2. Finally, half the rats in each of the CER conditioning treatments received extinction test trials of the noise CS in Context 1, while the remaining rats received those test trials in Context 2. Thus, this design factorially manipulated the presence of excitatory or neutral contextual stimuli during both conditioning and testing of a discrete CS. In comparison with the two groups of rats never preexposed to shock alone, attenuation in acquisition of conditioned suppression observed during test trials occurred only when CER conditioning had been administered in the excitatory Context 1, and this effect was manifested when testing occurred in either the excitatory Context 1 or the neutral Context 2. These results support the model of R. A. Rescorla and A. R. Wagner (1972) (in A. H. Black & W. F. Prokasy (Eds.) Classical Conditioning II, pp. 64–99, New York: Appleton-Century-Crofts) which asserts that contextual stimuli and sicrete CSs compete for limited associative strength supportable by a given US. 相似文献
872.
A representative nationwide survey of elderly in nursing home facilities was conducted by the Lutheran Council U.S.A. Visitation by family ministers and facility chaplains, a major study focus, was characterized by the elderly as not meeting their needs in terms of frequency and time available with clergy. Time constraints of the clergy are communicated to the elderly, who are understanding but nevertheless felt shortchanged. The elderly without visits from relatives or significant others are particularly vulnerable. Dominant themes within pastoral care visitation are highlighted.Dr. Uhlman is Director of Research and Evaluation and Reverend Steinke is Director of the Clinical Pastoral Education Program with Mental Health Services of the Roanoke Valley, 920 South Jefferson Street, Roanoke, Virginia 24016. The authors wish to acknowledge the Aid Association for the Lutheran Insurance Company and Concordia Teachers College (River Forest, Illinois), which assisted with financial costs and data analysis. Special recognition and appreciation should be noted for the elderly respondents whose participation made our experience both rewarding and enlightening. 相似文献
873.
Unlike earlier tests of an oversimplified version of this model, the validity of W. Mobley's (1977, Journal of Applied Psychology, 62, 237-240) original turnover model was fully investigated. Constructs that were neglected in prior studies were assessed and previously examined constructs were operationalized with more reliable measures. Measures of all constructs in Mobley's model were obtained from a survey of 192 hospital employees. Turnover data were collected a year following survey administration. Following the theoretical causal ordering of Mobley's constructs, each construct was regressed on all causally prior constructs. In general, each construct was accurately predicted by the linear combination of predictors representing its causal determinants. In the majority of instances, the best predictor of a model construct was the construct's immediate causal antecedent. Further, an alternative model was evaluated and compared with Mobley's model using path analysis. 相似文献
874.
875.
Kinetic subjective contours 总被引:2,自引:0,他引:2
876.
877.
Priming with and without awareness 总被引:6,自引:0,他引:6
878.
Motoric change subsequent to therapeutic intervention in infants and young children who have cerebral palsy: annotated listing of group studies 总被引:1,自引:0,他引:1
This annotated listing is of group reports pertaining to therapeutic strategies utilized with infants and young children who have cerebral palsy. The studies are organized by type of design used. 相似文献
879.
A longitudinal study of the development of hand preference in 152 adopted and 120 nonadopted (control) infants measured in natural behavioral situations at both 12 and 24 mo. of age is reported. Significant developmental trends were observed for both increasing strength and direction of handedness. Less than 10% of the infants exhibited a clear preference at 12 mo. of age, whereas about 30% were lateralized at 24 mo., with more boys than girls being left-handed. In contrast, over 90% of the parents of these children (both biological and adoptive parents of the adopted children and parents of the nonadopted children) were lateralized. Perhaps because so few infants were lateralized at either age, parent-offspring resemblances were inconsistent and the number of significant parent/child correlations was about that expected on the basis of chance alone. 相似文献
880.