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991.
A comparison between the reinforcement strength of self-administered and externally imposed brain stimulation was undertaken. Rats performed on a chain schedule in order to receive brain stimulation, either selfadministered or imposed, during the second component of the chain. Response rates during the first component of the chain schedule indicated that self-stimulation was more reinforcing than imposed stimulation. In addition, contrast, both positive and negative, seemed to be present. It was concluded that reinforcement strength may be enhanced when the subject controls the presentation of reinforcement.  相似文献   
992.
General activity subsequent to reward (R) and nonreward (N) was monitored at 5-sec intervals with a stabilimeter in the runway goal box. Activity of never-rewarded control Ss was also measured. In Expt 1 it was found that the frustration effect (difference between N- and R-trial activities) disappeared after about 40 sec of goal box confinement. This disappearance of the frustration effect was due to activity increase on R trials rather than activity decrease on N trials as a function of time. Comparison of N-trial activity with control group activity indicated that frustration does not dissipate within 60 sec. Expt 2 investigated activity following reward and nonreward as a function of reward magnitude. Evidence from these experiments suggests that the late R-trial activity increase results from frustration, possibly conditioned to apparatus cues on N trials.  相似文献   
993.
Continuous availability of a sand blocked tube elicited intense and persistent digging by laboratory rats. Neither training nor prior exposure to the apparatus were necessary for response initiation. Continuous presence of an open pile of sand would not elicit digging. No theoretical explanation is offered.  相似文献   
994.
The effects of the relationship between the presentation of a verbal stimulus (“right”) and an established reinforcer (M&Ms) on the reinforcement efficacy of the verbal stimulus was tested with three groups of retarded boys. Blocks of training and test trials alternated. During training of the Discriminative Group, “right” reliably preceded candy. For the Contiguous Group, “right” accompanied candy, and for the Random Group “right” and candy were programmed independently. “Right” promoted learning in the Discriminative Group but did not in the latter two groups. The results support Cairns' analysis of the often found failure of approval to be an effective reinforcer in laboratory tasks.  相似文献   
995.
996.
The purpose of this study was to investigate the affect, as measured by “Positive and Negative Affect Schedule” (PANAS), its influence on psychopathology, and to examine the effect of changing affect during cognitive behavioral therapy (CBT). The study was carried out at the psychotherapy training center, Karlstad University. The hypothesis was whether clients with mental disorders have a self‐destructive affective personality (low PA and high NA) and healthy individuals have a self‐actualizing personality (high PA and low NA). Thirty‐two healthy participants and 44 clients participated in the study. The clients were asked to fill in the PANAS once throughout CBT, either during evaluation, treatment or finishing phase, accordingly there were three different groups at different therapy phases. The healthy subjects were also asked to fill in the self‐report scale once. The comparison of the three phases of therapy and the four affective personality types showed a significant difference between the phases of therapy and the four affective personality types: totally 16 (of 22) and eight (of nine) clients measured at the evaluation and treatment phases, respectively, had a self‐destructive personality. However, at the end of therapy five (of 13) clients had a self‐actualizing personality characteristics, while only three of them were self‐destructive. Furthermore, the results indicate that affective personality does not seem to be a basic and stable personality trait, which could be altered by therapy. The affections measured by PANAS may be influenced by psychopathology and CBT, when conducted by candidate therapists it can be effective in terms of affect changes.  相似文献   
997.
The increasing emphasis on multicultural competence within psychotherapy continues to highlight the need for being sensitive to key differences between therapist and client. However, this attunement to the psychotherapeutic impact of therapist–client differences may obscure the equally critical need to evaluate ethical problems associated with therapist–client similarities. It will be argued that therapists treating clients who are demographically similar to themselves encounter a unique set of ethical challenges that warrant careful consideration and caution precisely because of therapist–client matching. The extant research on matching therapists and clients based on demographic similarities is discussed, with a particular emphasis on psychotherapeutic outcomes and client preferences. Attention then turns to the nonrational heuristics and biases that can often cloud therapists’ ethical decision making regarding the appropriate uses versus contraindications for demographically matching therapists and clients. Within the discussion of nonrational heuristics and biases, suggestions are offered for managing related challenges for ethical decision making.  相似文献   
998.
Background and Objectives: The negative impact of exposure to terror on mental health, as well as on the perceptions of each side of the conflict toward the other, is well-documented. However, the association between stereotyping, concomitant with perceived threat, and anxiety, was rarely investigated. The current study examined information processing attributes and exposure to terror as predictors of PTSD symptoms among youth at inter-group conflict, with stereotypical thinking toward a threatening out-group as a possible mediator. Design: Cross-sectional, with exposure to terror, need for cognitive structure (NCS), efficacy at fulfilling the need for closure (EFNC) and self-esteem, predicting stereotypical thinking and PTSD symptoms. Method: Ninth graders (N?=?263) from two residential areas in Israel, varying in their degree of exposure to terror, responded to a self-report questionnaire tapping the above variables. Results: Stereotypical thinking was found to mediate the association between exposure to terror and PTSD symptoms, but not the association between the NCS and EFNC interaction and PTSD symptoms. Conclusions: The findings support terror management theory, so that a negative and rigid perception makes it difficult to construct coherent world-view, thus contributing to aggregation of existential anxiety and PTSD symptoms.  相似文献   
999.
1000.
A number of countries allow bicyclists to perform a right turn on red (RTOR) at some specific intersections to promote cycling by reducing the required physical effort and trip time. Implementation of a rule that allows a RTOR for bicyclists at some intersections could lead not only to local effects at those intersections where the rule actually applies, but also to supralocal effects. Using an experimental survey approach, this study explores whether a so-called ‘spillover effect’ of the rule can be expected. This effect would imply that allowing bicyclists to turn right on red at some intersections causes them to also turn right on red more often at intersections where RTOR for bicyclists is not allowed.The answers from 768 respondents indicate that respondents with a high awareness of the existence of a RTOR rule for bicyclists (experimental group) turn right on red significantly more often at intersections where RTOR for bicyclists is not permitted than respondents with a low awareness of the rule (control group). This indicates that implementation of the RTOR rule for bicyclists can indeed lead to an increase in red light running at other intersections. This might lead to safety issues at intersections where RTOR for bicyclists is not permitted, since road authorities could have decided not to allow RTOR for bicyclists at these intersections for safety reasons.The study also finds that men, young people and people who generally perform more risky cycling behaviours have a higher tendency to perform non-permitted RTOR. These findings are in line with existing literature.  相似文献   
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