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61.
Neuronal activity regulated pentraxin (Narp) is a secreted protein that regulates α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors (AMPAR) aggregation and synaptogenesis. Mapping of Narp-positive neurons in brain has revealed it is prominently expressed in several limbic system projection pathways. Consistent with this localization pattern, Narp knockout mice show deficits in using the current value of a reinforcer to guide behavior, a critical function of the limbic system. To help assess whether this behavioral deficit is due to impairment of synaptogenesis during development or in modulating synaptic signaling in the mature brain, we have used a dominant negative Narp viral construct which blocks trafficking of endogenous Narp to axons. Focal injection of this viral construct into the medial prefrontal cortex (mPFC) of adult mice, a region containing Narp-positive projection neurons, blocked reinforcer devaluation. Thus, these results indicate that Narp released from mPFC neurons plays a key role in mediating synaptic changes underlying instrumental reinforcer devaluation.  相似文献   
62.
The aim of the present experiment was to extend the literature on hostility and a cerebral systems based model of sympathetic arousal to a vestibular-based stress. Several authors have concluded that autonomic stress reactivity in high hostile individuals must be interpersonally based, whereas healthy vestibular system functioning does not depend on interpersonal features. Utilizing a vestibular activation paradigm, skin conductance levels of 15 high hostile and 15 low hostile men were recorded after brief passive rotation about the vertical neuroaxis. It was expected that hostile individuals would exhibit higher skin conductance levels after rotation compared with low hostile individuals. The results confirmed expectations of heightened sympathetic tone among high hostiles subsequent to vestibular stress. Overall, the findings are interpreted to support a cerebral model of frontal region capacity limitation for regulation of vestibular stress that is independent of psychosocial mechanisms.  相似文献   
63.
64.
Two experiments refined procedures to study Pavlovian influences on goal-directed behavior in mice and studied the effects of CS-US relations in Pavlovian-instrumental interactions. Independent groups of mice underwent Pavlovian training to associate either a 10-sec or 2-min auditory stimulus (CS) with reward. We next assessed the ability of the response-contingent CS presentations to reinforce novel instrumental responding (conditioned reinforcement; CRf) or the ability of noncontingent CS presentations to increase ongoing instrumental responding (Pavlovian-instrumental transfer; PIT). Whereas 10-sec training conditions produced strong CRf (and no PIT), 2-min training conditions produced robust PIT (but no CRf).  相似文献   
65.
Participants were pretrained and tested on mutually entailed trigonometric relations and combinatorially entailed relations as they pertained to positive and negative forms of sine, cosine, secant, and cosecant. Experiment 1 focused on training and testing transformations of these mathematical functions in terms of amplitude and frequency followed by tests of novel relations. Experiment 2 addressed training in accordance with frames of coordination (same as) and frames of opposition (reciprocal of) followed by more tests of novel relations. All assessments of derived and novel formula‐to‐graph relations, including reciprocal functions with diversified amplitude and frequency transformations, indicated that all 4 participants demonstrated substantial improvement in their ability to identify increasingly complex trigonometric formula‐to‐graph relations pertaining to same as and reciprocal of to establish mathematically complex repertoires.  相似文献   
66.
A theoretically based, culture-fair test of new learning ability is predictive of academic achievement. A sample of 633 adults, 121 of minority status, drawn from urban private universities, colleges, and community colleges were given information as to the meanings of previously unknown words, sayings, similarities, and analogies. They were also tested for their existing knowledge of vocabulary, opposites, and analogies with a brief version of the Scholastic Assessment Test (SAT). New learning ability proved to be culture-fair, reliable, and predictive of grades and of the brief version of the SAT.  相似文献   
67.
The number of individuals receiving genetic counseling for hereditary breast and ovarian cancer syndrome has steadily risen. To triage patients for genetic counseling and to help reduce the amount of time needed by a genetic counselor in direct patient contact, many clinics have implemented the use of family history questionnaires. Although such questionnaires are widely used, scant literature exists evaluating their effectiveness. This article explores the extent to which family history questionnaires are being used in Ontario and addresses the utility of such questionnaires in one familial cancer clinic. By comparing the pedigrees created from questionnaires to those updated during genetic counseling, the accuracy and effectiveness of the questionnaires was explored. Of 121 families recruited into the study, 12% acquired changes to their pedigree that led to a revised probability estimate for having a BRCA1 or BRCA2 mutation and 5% acquired changes that altered their eligibility for genetic testing. No statistically significant difference existed between the eligibility for genetic testing prior to and post counseling. This suggests that family history questionnaires can be effective at obtaining a family history and accurately assessing eligibility for genetic testing. Based on the variables that were significantly associated with a change in probability estimate, we further present recommendations for improving the clarity of such questionnaires and therefore the ease of use by patients.  相似文献   
68.
Pigeons were trained to match the number of responses made during a production phase to the number of keylight flashes (2, 4, or 6) in a previous sample phase. In Experiment 1, there were 2 conditions in which the flashes were programmed to occur at a constant rate or within a constant overall duration. For both conditions, although accuracy was relatively low, responding increased linearly with flash number and coefficients of variation decreased. Positive transfer to novel numbers was obtained only when test and baseline trials had the same temporal organization, but multiple regressions revealed significant control by number independently of temporal cues. In Experiment 2, flashes were programmed to occur pseudorandomly to degrade the validity of temporal cues. Results were similar to in Experiment 1. A prototype response class model accounted for the major features of the data. According to the model, responses during the production phase are shaped into higher order units that are associated with different stimulus numbers and function as a rough category scale of numerosity.  相似文献   
69.
Persistent symptoms of nausea, distress, and vomiting triggered by reminders of cancer treatment were examined among 273 Hodgkin's disease survivors, 1 to 20 years posttreatment. Prevalence rates were high for distress and nausea but low for vomiting. Retrospective report of anticipatory symptoms during treatment was the strongest predictor of persistent symptoms, suggesting that treatment-induced symptoms are less likely to persist if conditioning does not occur initially. Time since treatment was also a significant predictor, with patients more recently treated more likely to experience persistent symptoms. Thus, an explanatory model based on classical conditioning theory successfully predicted presence of persistent symptoms. Symptoms also were associated with ongoing psychological distress, suggesting that quality of life is diminished among survivors with persistent symptoms. Recommendations for prevention and treatment of symptoms are discussed.  相似文献   
70.
Robert A. Holland 《Synthese》1992,92(3):349-370
I argue that we need not accept Quine's holistic conception of mathematics and empirical science. Specifically, I argue that we should reject Quine's holism for two reasons. One, his argument for this position fails to appreciate that the revision of the mathematics employed in scientific theories is often related to an expansion of the possibilities of describing the empirical world, and that this reveals that mathematics serves as a kind of rational framework for empirical theorizing. Two, this holistic conception does not clearly demarcate pure mathematics from applied mathematics. In arguing against Quine, I present a formal account of applied mathematics in which the mathematics employed in an empirical theory plays a role that is analogous to the epistemological role Kant assigned synthetic a priori propositions. According to this account, it is possible to insulate pure mathematics from empirical falsification, and there is a sense in which applied mathematics can also be labeled as a priori.I am especially indebted to Michael Friedman for his valuable suggestions and criticisms of this paper. I would also like to thank Mark Wilson, Anil Gupta, and Arthur Fine for their comments and encouragement.  相似文献   
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