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961.
A blind woman who is mentally retarded was employed (as peer care-giver) to promote and eventually share the occupational engagement of a deaf-blind adolescent (trainee) who was dependent on physical prompting. A computer-aided program was used to provide objects for the responses and facilitate orientation and mobility. The trainee was also exposed to the computer-aided program individually to assess the effects of the program per se. The results showed highly positive changes only in the condition involving the peer care-giver. In this condition, the trainee performed high frequencies of correct responses. Moreover, the care-giver managed to share responding with the trainee. Technical and practical aspects of the findings are discussed.  相似文献   
962.
963.
In this paper a case is used to demonstrate how ethical analysis enables health care professionals, patients and family members to make treatment decisions which ensure that medical technologies are used in the overall best interests of the patient. The claim is made and defended that ethical analysis can secure four beneficial outcomes when medical technologies are employed: (1) not allowing any medical technologies to be employed until the appropriate decision makers are identified and consulted; (2) insisting that medical technologies be employed not merely to promote the medical interests of the patient but rather on the basis of their ability to contribute to the overall well-being of the patient; (3) challenging caregivers to reflect on the dynamic interplay between their conscious and unconscious values and consequent determinations of what is in the patient's best interests; and (4) providing a justification for selected interventions which makes possible rational dialogue between caregivers espousing different viewpoints about treatment options.  相似文献   
964.
Phonetic segments are coarticulated in speech. Accordingly, the articulatory and acoustic properties of the speech signal during the time frame traditionally identified with a given phoneme are highly context-sensitive. For example, due to carryover coarticulation, the front tongue-tip position for HI results in more fronted tongue-body contact for a /g/ preceded by /l/ than for a /g/ preceded by /r/. Perception by mature listeners shows a complementary sensitivity—when a synthetic /da/-/ga/ continuum is preceded by either /al/ or /ar/, adults hear more /g/s following HI rather than Irl. That is, some of the fronting information in the temporal domain of the stop is perceptually attributed to /l/ (Mann, 1980). We replicated this finding and extended it to a signaldetection test of discrimination with adults, using triads of disyllables. Three equidistant items from a /da/-/ga/ continuum were used preceded by /al/ and /ar/. In the identification test, adults had identified item ga5 as “ga”, and dal as “da”, following both /al/ and /ar/, whereas they identified the crucial item d/ga3 predominantly as “ga” after /al/ but as “da” after /ar/. In the discrimination test, they discriminated d/ga3 from dal preceded by /al/ but not /ar/; compatibly, they discriminated d/ga3 readily from ga5 preceded by /ar/ but poorly preceded by /al/. We obtained similar results with 4-month-old infants. Following habituation to either ald/ga3 or ard/ga3, infants heard either the corresponding ga5 or dal disyllable. As predicted, the infants discrimi-nated d/ga3 from dal following /al/ but not /ar/; conversely, they discriminated d/ga3 from ga5 following /ar/ but not /al/. The results suggest that prelinguistic infants disentangle consonant-consonant coarticulatory influences in speech in an adult-like fashion.  相似文献   
965.
The orienting response (OR) is a specific behavioral act directed towards extraction of information from the environment. Head and eye movements represent only the tip of the iceberg of internal responses, which includes vascular modifications, EEG changes, and event-related potentials. Two mechanisms of the OR have to be differentiated: voluntary and involuntary. In the event-related potential, such a differentiation is expressed in mismatch negativity (involuntary effect) and processing negativity (voluntary effect). Single unit studies have shown that hippocampal neurones are simulating specific features of the OR as a response to novelty. Repeated presentation of stimuli results in a selective habituation of novelty detectors in hippocampus and of the OR. The trace of a standard stimulus formed at the level of hippocampal neurones matches the features of the standard stimulus and can be called a “neuronal model of the stimulus.” The OR is triggered by mismatch between the test stimulus and the elaborated neuronal model, and is activated by verbal instruction, by reinforcement during the initial stage of conditioned reflex elaboration, and by differentiation of signal and non-signal stimuli. A promising new area of practical application of the OR lies in the evaluation of a corridor of optimal functional state for efficient computer-based learning. Registration of the OR and defensive responses can be used for an objective evaluation of the functional state of the student, or, in a wider sense, of the industrial operator. New avenues of OR research are opened by recent techniques that isolate single-trial event related potentials, and their correlation with autonomic and behavioral manifestations of the OR. The combination of single unit recording with such isolated event related potentials can elucidate the neuronal basis of OR generation. Intracellular recording combined with dye injection can be used for analysis of the synaptic contacts involved in generation of the OR. Integration of macro and micro levels of OR organization can be achieved in a computerized model that can be used for simulation and planning of experiments. A step-by-step improvement of the model will accumulate knowledge about the OR as an important mechanism of information processing.  相似文献   
966.
OPTIMISM AND FUNDAMENTALISM   总被引:2,自引:0,他引:2  
  相似文献   
967.
Abstract— This article compares studies that use event-related brain potential (ERP) and eye movement data to examine changes in reading behavior when a text is read twice. Although the types of information provided by these methodologies are different, both indicate that rereading a text facilitates many aspects of processing. ERPs provide a method for measuring comprehension and memory processes separately, while eye movements provide a continuous record of performance and allow changes in reading behavior to be localized to specific words. The results from these studies are compatible. However, converging evidence is not always found when different paradigms are contrasted, and diverging results can provide important information. To facilitate comparison across experiments, we suggest using a common set of materials for both paradigms. We conclude that comparing the results of research based on more than one paradigm provides a more complete understanding of the processes involved in reading.  相似文献   
968.
STATED WILLINGNESS TO PAY FOR PUBLIC GOODS:   总被引:3,自引:0,他引:3  
Abstract— In the contingent valuation method for the valuation of public goods, survey respondents are asked to indicate the amount they are willing to pay (WTP) for the provision of a good. We contrast economic and psychological analyses of WTP and describe a study in which respondents indicated their WTP to prevent or to remedy threats to public health or to the environment, attributed either to human or to natural causes. WTP was significantly higher when the cause of a harm was human, though the effect was not large. The means of WTP for 16 issues were highly correlated with the means of other measures of attitude, including a simple rating of the importance of the threat. The responses are better described as expressions of attitudes than as indications of economic value, contrary to the assumptions of the contingent valuation method.  相似文献   
969.
We find three factors to be associated with use of cost-benefit rules in everyday decisions. These are effectiveness in achieving desirable life outcomes, intelligence, and training in economics. We argue that these empirical findings support the claim that cost-benefit reasoning is normative.  相似文献   
970.
Selected empirical research on consultative problem solving is reviewed. Although there is general support for the effectiveness of consultation in resolving a variety of presenting problems and in improving consultees' skills for solving future problems, there is a need for additional methods to facilitate the process. Direct training of consultees in behavior management, communication, and consultation process skills is advocated as one means of attaining this goal.  相似文献   
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