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The author focuses on the trend in the family therapy field toward an expanded view of families in the context of their social environments. Within this broader eco-system perspective attention is given to individual-family-social network interrelations with implications for the family therapist.An earlier version of this paper was presented at the American Association for Marriage and Family Therapy, Dallas, Texas, October 29, 1982. Appreciation is expressed to Alice Lynn for her comments and suggestions on an earlier draft of this paper. The author has also benefitted from discussions with Douglas Sprenkle on paradigms and contexts.  相似文献   
903.
The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects.  相似文献   
904.
In two experiments, we assessed the ability of a feedback stimulus during helplessness training to reduce the performance deficits common to inescapable shock. In each experiment, four groups of rats were exposed to either escapable shock (E), inescapable shock with a feedback stimulus following shock termination (Y-FS), inescapable shock with no feedback stimulus (Y-NFS), or no shock (N). The feedback stimulus eliminated the interference effects of inescapable shock when tested with an FR-3 lever press escape task (Experiment 1) or on an FR-1 task with a 3-s delay between the response and shock termination (Experiment 2). These results suggest that stress-induced biochemical changes may mediate the interference effects seen in inescapably shocked rats.  相似文献   
905.
In two experiments, fear was conditioned to the situational cues in one compartment of a hurdle-jumping apparatus and was then extinguished. Subsequently, either one shock (Experiment 1) or three or nine shocks (Experiment 2) were given in a situation distinctively different from that in which conditioning and extinction had taken place. Although some associative strength between the situational cues and fear was shown to have remained after extinction, in neither experiment did the postextinction-shock treatment increase the fear elicited by these cues: Escape-from-fear performance was no better in the shocked groups than in control groups given no additional shock. Thus, the nonassociative hypothesis which postulates that inflating the value of the representation of the UCS with shock-alone presentations can reinstate the extinguished fear of a stimulus was not supported. Rather, the results showed that, after extinction, an increase in fear of a simulus depended on further conditioning to that stimulus. The data also indicated that the nonvisual components of the situational cues predominated over the visual component.  相似文献   
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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   
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