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921.
Studies of extinction of a target cue in compound with another excitor have produced evidence of both deepened and attenuated extinction relative to elemental extinction. The present experiments sought to resolve this discrepancy by assessing the effect of the extinction context-unconditioned stimulus (US) association on compound extinction. In an ABC renewal situation with rats, Experiment 1 replicated the observation that enhanced extinction (i.e., reduced conditioned suppression) occurs as a result of nonreinforcement in compound with a concurrent excitor. In Experiment 2, inflation of the extinction context-US association through unsignaled, intertrial US presentations reversed the effect of a concurrent excitor (i.e., extinction with a concurrent excitor was less effective than elemental extinction). Experiment 3 compared compound extinction and second-order conditioning with respect to the effect of context inflation, and produced results incompatible with the view that second-order conditioning contributed to the results of Experiment 2. In Experiment 4, a concurrent excitor enhanced extinction in ABC renewal and attenuated extinction in AAC renewal. The present results suggest that the effect of a concurrent excitor during extinction depends on the strength of the extinction context-US association, thereby confirming predictions of the sometimes -competing retrieval model of associative acquisition and extinction.  相似文献   
922.
Phonation is a fundamental feature of human communication. Control of phonation in the context of speech-language disturbances has traditionally been considered a characteristic of lesions to subcortical structures and pathways. Evidence suggests however, that cortical lesions may also implicate phonation. We carried out acoustic and perceptual analyses of the phonation of /a/ in 60 males with aphasia (20 Wernicke's, 20 Broca's, 20 subcortical aphasia) and 20 males matched in age with no neurological or speech-language disturbances. All groups with aphasia were significantly more impaired on the majority of acoustic and perceptual measures as compared with the control speakers. Within the subjects with aphasia, subjects with subcortical aphasia were more impaired on most measures compared to subjects with Broca's aphasia, and they, in turn, more impaired than those with Wernicke's aphasia. Lesions in regions involved in sound production-perception result in dysfunction of the entire neurocognitive system of articulation-phonological language processing.  相似文献   
923.
Although it is well known that under-referral of colon cancer patients to cancer genetics clinics is a chronic problem, no study has yet examined why physicians may be ordering testing independently rather than referring patients to cancer genetics clinics. The current study explored variables which may impact a physician’s preference for ordering testing independently or referring patients to outside cancer genetics experts. An online questionnaire, distributed to the membership of the American College of Gastroenterology and the American Society of Colorectal Surgeons, yielded responses from 298 physicians. Motivations to refer to cancer genetics clinics rather than order testing independently included fear of genetic discrimination and a belief that patients benefit from genetic counseling about the risks, benefits and consequences of testing. These results suggest that in order to increase referrals, genetic counselors must educate physicians about the unique benefits patients receive from participating in genetic counseling.  相似文献   
924.
The purpose of this study was to examine the effectiveness of evidence-based recruitment and retention strategies for a longitudinal, family-based HIV prevention intervention study targeting adolescents in psychiatric care by (1) determining consent rate (recruitment), rate of participation at the first intervention session (retention), and follow-up attendance rate (retention); and (2) examining socio-demographic factors, family-level processes, sexual risk-related indices, and intervention factors (i.e., treatment arm) associated with study retention. Only one-third of the families contacted ultimately enrolled in the study. 81% of those enrolled participated in the workshop and 72% attended the booster sessions with no significant differences between families on any variable based on attendance. Retention over 1?year was 85% and did not differ by treatment arm. Strategies employed were successful at retaining families once they were enrolled. Findings highlight barriers to enrollment for adolescents in psychiatric care and suggest that it may be critical to integrate HIV prevention programs within community-based mental health services in order to counteract recruitment challenges.  相似文献   
925.
This study investigated whether initial self-control exertion by dogs would affect behavioral approach toward an aggressive threat. Dogs were initially required to exert self-control (sit still for 10 min) or not (caged for 10 min) before they were walked into a room in which a barking, growling dog was caged. Subject dogs spent 4 min in this room but were free to choose where in the room they spent their time. Approaching the unfamiliar conspecific was the predisposed response, but it was also the riskier choice (Lindsay, 2005). We found that following the exertion of self-control (in comparison with the control condition), dogs spent greater time in proximity to the aggressor. This pattern of behavior suggests that initial self-control exertion results in riskier and more impulsive decision making by dogs.  相似文献   
926.
This article discusses the Stage Climbing model, a cognitive behavioral therapy based system designed to identify the beliefs and attitudes typical of different developmental life stages that may explain or identify obstacles to resolving present day relationship issues. We suggest that self-defeating beliefs and behaviors characteristic of dysfunctional couples give evidence of one or both partners operating from a stage of development or level of maturity in that aspect of the relationship that is different from what would be optimal given their presenting issues and therapeutic goals.  相似文献   
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929.
Two studies on the relations between various styles of defense and the power or validity of self-reports on objective personality questionnaires. The power of individual items on the Rotter Internal-External Locus of Control scale to discriminate between subjects defined as internals or externals by a median-cut procedure using the total score was not affected by the presence Or absence of a projective defensive style. However, the presence of repressive tendencies did appear to restrict item power. Prediction from two achievement scales taken from Gough's California Psychological Inventory was not influenced by level of repression, was affected somewhat adversely by a projective style, and was most clearly contaminated by a rationalizing defense. It was proposed that the differential effects of defensive styles upon the validity of personality tests depended upon the convergence or divergence of the cognitive operations involved in the type of defense and in the type of personality measure.  相似文献   
930.
Summary: Presented definitions for the construct of ambiguity tolerance. The measun: of ambiguity tolerance (MAT-50) had high internal reliability (r = .88) and high test-retest reliability (r = .86) over a 10-to-12 week period. A content analysis of the measure and a subjective imalysis by 20 graduate students indicated adequate content validity. A multivariate comparison with two other ambiguity measures, two rigidity measures, and a short dogmatism measure provided strong evidence for criteria-related validity. Finally, four independent empirical studies showed good construct validity.  相似文献   
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