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41.
Food deprived, heterogeneous strain (HS/IBG) mice were trained on two different discrimination tasks for food reinforcement. In one experiment animals were trained to make spatial discriminations in a T maze. Immediately after training they were given subcutaneous injections of either substance P (1 ng/g) or vehicle. Twenty-four hours later the animals were given reversal training in the same maze. The results showed that substance P-treated animals took significantly longer to acquire the reversal habit than did control mice. In a second experiment, animals were trained to make visual discriminations in a T maze. Immediately after reaching acquisition criterion animals were injected with either substance P (1 ng/g) or vehicle. Different groups of mice were retrained on the same task either 1, 2, 3, or 7 days after original learning. Savings scores were calculated and, at every interval, substance P-treated mice retained the task better than control animals. One interpretation of these data is that substance P-treated mice remembered the original task significantly better than vehicle-injected control animals.  相似文献   
42.
Fixation point digits have been widely used in tachistoscopic laterality studies as a simple and convenient means of ensuring unihemispheric projection of stimulus materials to the hemispheres. Previous findings demonstrate that fixation digits do not influence asymmetries in recognition accuracy studies with adult Ss. Present results, comparing four conditions differing in their use of fixation digits, show that in the naming latency paradigm the requirement to remember and report fixation control digits significantly augments RVF superiority. Implications for other latency tasks are discussed.  相似文献   
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This study investigates the separate activation versus coactivation issue for redundant targets in a simple letter-detection paradigm with latency as the dependent variable. The results of a one-response visual-search task are reported. Since, on single-target trials, only the target was presented and no accompanying noise element, no “distraction decrement” caused by irrelevant noise elements (Grice et al., 1984) was to be expected. The data obtained showed a clear redundantsignal effect. Subsequent detailed analysis of the latency data using Miller’s (1982) procedure indicated that the results were consistent with a separate activation model and failed to provide convincing evidence in favor of coactivation models. A further analysis of the data indicated that, in the present study, the separate channels were negatively correlated for a range of fast RTs and positively correlated for intermediate and larger RTs. No evidence in favor of Grice et al.’s (1984) distraction-decrement hypothesis was found. The conclusions of this study are that (1) a separate activation model summarizes the essential features of information processing in this simple visual search task, and (2) no convincing evidence in favor of coactivation in visual search tasks has been reported in the literature up to now.  相似文献   
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Recent studies have demonstrated that positive verbal feedback enhances males' intrinsic motivation for a task, while decreasing that of females. This result has been attributed to differential socialization forces which make the controlling aspects of rewards more salient for females as opposed to males, for whom the informational aspects are prepotent. A weakness in this conclusion stems from the use of a masculine sex-linked task in prior experiments, producing a result which may be due to gender congruence/incongruence rather than to socialization differences. Two laboratory experiments were performed to examine the effects of verbal praise on intrinsic motivation, controlling for sex-typing of the experimental activity. Experiment I found that verbal praise increased females' and males' intrinsic motivation on both a feminine and masculine task, and intrinsic motivation was higher for sex-appropriate than sex-inappropriate tasks. The sexes did not show a differential pattern of response to praise. In Experiment 2, verbal praise also enhanced sex-role traditional females' intrinsic motivation on the same activity used in prior research. These results suggest that socialization content has changed sufficiently to make concerns about competence and self-determination equally salient for females and males.  相似文献   
47.
To evaluate a contingency interpretation of conditioned inhibition (CI), rats were given “explicity unpaired” training in which the locus and duration of a CS within the inter-US (shock) interval were systematically manipulated for different groups. Summation and retardation tests in Experiment 1 indicated that stronger CI resulted from both a backward and a trace CS than from a midlocus CS of equal or greater duration. Complementing these findings, the same tests in Experiment 2 showed that, by comparison with novel-stimulus controls, CI developed to a trace CS but not to a mid-locus CS, nor to a trace CS that was accompanied by an immediate signal for the US. These findings argue against a contingency interpretation of CI and favor a contiguity interpretation stressing the short-term rehearsal of stimulus events. Such rehearsal of the US allows a backward CS, but not a mid-locus CS with an extended US-CS interval, to be discriminated as a signal for nonreinforcement, and thus to develop as a conditioned inhibitor. Similarly, excitatory conditioning to the memory trace of a CS allows the nominal trace CS to develop as a signal for nonreinforcement, and thus as a conditioned inhibitor, but not when its memory trace is overshadowed by another CS that immediately precedes the US. In short, the development of CI is facilitated when excitation is mediated by the memorial processing of either the US or a discrete CS for the US rather than by contextual cues.  相似文献   
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The effectiveness of intense specialised multi-family therapy (ISMFT) for 111 multi-stressed families, and the therapeutic alliance as a possible predictor of outcome, were examined. A repeated measures design was used, where changes in all ISMFT phases (preparation, multi-family therapy and follow-up) were assessed and compared for both mothers and fathers. Evidence was found for improved family functioning after the therapy period, which was maintained at 3 months follow-up, although the multi-stressed families still functioned in the problematic range. The therapy did however not decrease parenting stress, or did so only temporarily. Observations of the therapeutic alliance with the System for Observing Family Therapy Alliances (SOFTA) scales indicated that high therapist engagement was related to positive therapy outcomes, both at the start of therapy and later. High family engagement also predicted therapy effectiveness, but only at the start of therapy. The present study shows that solution-focused multi-family therapy at least seems to provide the first step in alleviating problems in multi-stressed families.  相似文献   
50.
Research shows that parents have a strong influence on the party preferences of their children. Yet little is known about how such preferences are transmitted in multiparty systems with weak party identification and high electoral volatility. We propose a model of intergenerational transmission that includes both direct effects of parents' party preferences on those of their children, as well as indirect effects through left–right and issue positions. We test this model with original survey data of Dutch adolescents (14–20 years old) and their parents (N = 751 adolescent-parent pairs). We find two paths through which parents exert influence on the party preferences of their adolescent children. On the first path, parental party preferences function as a direct predictor of adolescent party preferences. On the second path, adolescent left–right and issue positions function as a mediator between parental left–right and issue positions and adolescent party preferences, with the effect of left–right positions being stronger than that of issue positions. The frequency with which adolescents discuss political topics with their parents moderates these effects.  相似文献   
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