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71.
Typically, functional analyses of severe problem behavior have been conducted in two ways: (a) The target response is reinforced immediately after it occurs, or (b) the target response is reinforced on some schedule thought to mimic a naturally occurring schedule. We evaluated the effects of contingency strength in reducing levels of problem behavior with 2 participants who had been diagnosed with developmental disabilities. Results showed that under a neutral contingency, one in which the probability of reinforcement for aggression was equal to the probability of reinforcement for the nonoccurrence of aggression, rates of aggression were suppressed to low levels for both participants.  相似文献   
72.
This article describes an approach for assessing and comparing complex cognition in rhesus monkeys and pigeons by training them in a sequence of synergistic tasks, each yielding a whole function for enhanced comparisons. These species were trained in similar same/different tasks with expanding training sets (8, 16, 32, 64, 128 … 1024 pictures) followed by novel‐stimulus transfer eventually resulting in full abstract‐concept learning. Concept‐learning functions revealed better rhesus transfer throughout and full concept learning at the 128 set, versus pigeons at the 256 set. They were then tested in delayed same/different tasks for proactive interference by inserting occasional tests within trial‐unique sessions where the test stimulus matched a previous sample stimulus (1, 2, 4, 8, 16 trials prior). Proactive‐interference functions revealed time‐based interference for pigeons (1, 10 s delays), but event‐based interference for rhesus (no effect of 1, 10, 20 s delays). They were then tested in list‐memory tasks by expanding the sample to four samples in trial‐unique sessions (minimizing proactive interference). The four‐item, list‐memory functions revealed strong recency memory at short delays, gradually changing to strong primacy memory at long delays over 30 s for rhesus, and 10 s for pigeons. Other species comparisons and future directions are discussed.  相似文献   
73.
This paper explores patients’ views and experiences of undergoing treatment-focused BRCA1 and BRCA2 genetic testing (TFGT), either offered following triaging to clinical genetics (breast cancer) or as part of a mainstreamed care pathway in oncology (ovarian cancer). Drawing on 26 in-depth interviews with patients with breast or ovarian cancer who had undergone TFGT, this retrospective study examines patients’ views of genetic testing at this point in their care pathway, focusing on issues, such as initial response to the offer of testing, motivations for undergoing testing, and views on care pathways. Patients were amenable to the incorporation of TFGT at an early stage in their cancer care irrespective of (any) prior anticipation of having a genetic test or family history. While patients were glad to have been offered TFGT as part of their care, some questioned the logic of the test’s timing in relation to their cancer treatment. Crucially, patients appeared unable to disentangle the treatment role of TFGT from its preventative function for self and other family members, suggesting that some may undergo TFGT to obtain information for others rather than for self.  相似文献   
74.
The central question in Heidegger's philosophy, early and late, is that concerning the meaning of being. Recently, some have suggested that Heidegger himself interprets being to mean presence (Anwesen, Anwesenheit, Praesenz), citing as evidence lectures dating from the 1920s to the 1960s. I argue, on the contrary, that Heidegger regards the equation between being and presence as the hallmark of metaphysical thinking, and that it only ever appears in his texts as a gloss on the philosophical tradition, not as an expression of his own ontological commitments. In his early work Heidegger seeks to confront and even correct the traditional interpretation of being by challenging its narrow preoccupation with presence and the present. By the 1930s, however, he abandons the idea that there is anything to‐be intrinsically right or wrong about with regard to the meaning of being and turns his attention instead to what he calls ‘appropriation’ (Ereignis) or the truth of being, that is, the essentially ahistorical condition for the possibility of all historically contingent interpretations of being, including the metaphysical interpretation of being as presence.  相似文献   
75.
Blood-oxygenation-level-dependent signal was measured with functional magnetic resonance imaging in 24 healthy young subjects (12 men and 12 women) during viewing of angry, fearful, and neutral male and female face pictures. Exposure to angry male as opposed to angry female faces activated the visual cortex and the anterior cingulate gyrus significantly more in men than in women. A similar sex-differential brain activation pattern was present during exposure to fearful but not neutral faces. Previous behavioral studies indicate enhanced physiological arousal in men but not in women during exposure to angry male as opposed to female faces, and brain imaging studies have shown that the occipital cortex and the anterior cingulate gyrus are influenced by activity in the autonomic nervous system as well as by visual attention. Hence, we suggest that the elevated occipital and anterior cingulate activation in men during confrontation with other angry and fearful males may reflect enhanced vigilance in a potentially dangerous situation.  相似文献   
76.
Goals are central to current treatments of work motivation, and goal commitment is a critical construct in understanding the relationship between goals and performance. Inconsistency in the measurement of goal commitment hindered early research in this area but the nine-item, self-report scale developed by Hollenbeck, Williams, and Klein (1989b), and derivatives of that scale, have become the most commonly used measures of goal commitment. Despite this convergence, a few authors, based on small sample studies, have raised questions about the dimensionality of this measure. To address the conflicting recommendations in the literature regarding what items to use in assessing goal commitment, the current study combines the results of 17 independent samples and 2918 subjects to provide a more conclusive assessment by combining meta-analytic and multisample confirmatory factor analytic techniques. This effort reflects the first combined use of these techniques to test a measurement model and allowed for the creation of a database substantially larger than that of previously factor analyzed samples containing these scale items. By mitigating sampling error, the results clarified a number of debated issues that have arisen out of previous small sample factor analyses and revealed a five-item scale that is unidimensional and equivalent across measurement timing, goal origin, and task complexity. It is recommended that this five-item scale be used in future research assessing goal commitment. Copyright 2001 Academic Press.  相似文献   
77.
78.
A conditional approach to dispositions is developed in which dispositional constructs are viewed as clusters of if-then propositions. These propositions summarize contingencies between categories of conditions and categories of behavior rather than generalized response tendencies. A fundamental unit for investigating dispositions is therefore the conditional frequency of acts that are central to a given behavior category in circumscribed situations, not the overall frequency of behaviors. In an empirical application of the model, we examine how people's dispositional judgments are linked to extensive observations of targets' behavior in a range of natural social situations. We identify categories of these social situations in which targets' behavior may be best predicted from observers' dispositional judgements, focusing on the domains of aggression and withdrawal. One such category consists of subjectively demanding or stressful situations that tax people's performance competencies. As expected, children judged to be aggressive or withdrawn were variable across situations in dispositionally relevant behaviors, but they diverged into relatively predictable aggressive and withdrawn actions in situations that required the social, self-regulatory, and cognitive competencies they lacked. Implications of the conditional approach for personality assessment and person perception research are considered.  相似文献   
79.
Summary We have entered into a new era of medical achievement with the development of successful transplantation of human organs. The transplantation of the heart has aroused the greatest scientific interest and at the same time created serious new problems of an ethical and legal nature. It has been necessary to develop new criteria to determine the moment of death of the donor in order to ensure continued life for the recipient. The decision of the moment of death should be made by a small team of skilled physicians interested in furthering this important development, but not as emotionally involved as are the surgeons awaiting the chance to prolong their patient's life with a new heart. Available and suitable hearts will probably always be in very short supply, and the selection of recipients will therefore become critical if the procedure proves to be widely acceptable.New laws will be essential before this process can be adopted in many states and countries. The cost in terms of total resources is so large that careful evaluation of the long-term results must be undertaken after a reasonable number of patients have been operated on and observed, perhaps at the end of the second year following the first procedure. Since the cost of each operation of this type approximates that of the education of several young physicians who could care for thousands of patients during their life span, a good hard look at the potential benefits and ultimate values is in order. At this point in time it is extremely important that this type of surgery be encouraged but limited to those prepared to undertake it with maximum skill and minimal risk. At present it must be recognized as a great experiment rather than a therapeutic triumph for general application.  相似文献   
80.
Three experiments were conducted to study the effects of enactive imagery (EI) on associative learning. In Experiment I, groups of Ss rated 226 verbs on EI and frequency. In Experiments II and III, Ss learned a 24- and a 16-item list, respectively. The lists consisted of the four possible stimulus-response combinations of high (H) and low (L) EI verb pairs: H-H, H-L, L-H, L-L. In both experiments, EI was found to be a significant factor on the stimulus side, performance being superior when the stimulus was of high EI. In Experiment III, the response EI main effect and the Stimulus by Response EI interaction were also found to be significant. The results indicated that like the imagery evoked by nouns, the EI evoked by verbs facilitates learning.  相似文献   
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