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61.
Tachistoscopic presentation of stimuli on IBM PC-compatible computers is limited by a number of factors, including video retrace rates, screen scrolling, and the shape and density of picture elements. A method is presented for overcoming these difficulties through the use of enhanced graphic adapters or video graphic arrays. A C-language program demonstrates (1) synchronous scroll-free displays achieved by writing alternating images to “hidden” pages of video memory, (2) alternative techniques for erasing images, and (3) use of an empirically derived aspect ratio to produce symmetrical figures.  相似文献   
62.
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   
63.
Subjects had to make a “remove” or “do not remove” life-sustaining measures decision in three right to die cases where the patients differed in competence; for half the subjects, a living will was present in all the cases, whereas, for the other half, it was not. Subjects also gave their determinative reasons for their decisions. Support for the right to die varied by case, but not by competency, or by the presence of a living will. The subjects' reasons were highly predictive of their decisions, and related to the way case-specific facts were construed, revealing a number of disparities between the way courts and citizens construe whether the patient's condition is “terminal,” “irreversible,” and “painful,” or not. Beyond construing facts differently, the results also revealed a disparity between evolving case law and the community's “common sense justice” over a fundamental belief: whether dying is seen as private matter, outside the bounds of State intervention, or not.  相似文献   
64.
A recent stimulus-response compatibility model was used to provide a performance evaluation of an experimental notation for the keyboard in which pitch varies horizontally in visual space. One hundred and twenty subjects performed a choice reaction time task using either the horizontal notation or a more traditional vertical notation. Half the subjects in each notation group received white noise and half received pitch-varying feedback with responses. A horizontal display advantage was revealed when rules of the model were applied to data analyses. Further, the horizontal display advantage was not dependent on the nature of the feedback. In a second experiment, performance of musicians and non-musicians was compared using the horizontal and vertical notations. Musicians' performance was uniformly better than that of non-musicians, and did not differ with notation orientation. The findings support the use of non-traditional horizontal notations for novice performance on a keyboard instrument.  相似文献   
65.
The current study tests for the presence of differential order effects in evaluation tasks with consistent and inconsistent evidence as predicted by the Hogarth and Einhorn (1992) belief-adjustment model. The results, based on both between-subjects and within-subjects experiments, demonstrate that there were significant recency effects with inconsistent evidence as predicted, larger recency effects when the inconsistent evidence was farther apart in subjective value as predicted, and significant recency effects even when subjects were given training designed to both help them understand the task as completely as possible and to be better able to assess the pieces of evidence. By including a within-subjects design, we were able to demonstrate that the difference in subjective value between two pieces of evidence is the primary factor influencing the magnitude of the recency effect, regardless of whether the evidence is consistent or inconsistent. This latter finding is unique and contrary to previous research and theory.  相似文献   
66.
In a randomized clinical trial, multisystemic family preservation was shown to significantly reduce rates of criminal activity and incarceration in a sample of 84 serious juvenile offenders and their multi-need families. In the current study, archival records were searched for re-arrest an average of 2.4 years post-referral. Survival analysis showed that youths who received multisystemic family preservation were less likely to be re-arrested than were youths who had received usual services. Such results represent the first controlled demonstration that family preservation, when delivered via a clearly specified treatment model, has lasting effects with serious juvenile offenders. Implications for family preservation and juvenile justice research are discussed.  相似文献   
67.
This study explored one mechanism through which acute disaster stress (injury, life threat, property damage, loss) may produce lasting psychological distress (depression, anxiety, somatization, hostility). More specifically, the study examined the mediating roles of seven domains of chronic stress (marital, parental, filial, financial, occupational, ecological, physical) within a sample of 930 disaster victims and controls. The results provided strong support for the hypothesis that chronic stress mediates the long-term effects of acute disaster stress on psychological distress. The main effects of loss, though limited in strength, were completely explained by victims’ higher financial, marital, filial, and physical stress. The effects of injury, though quite strong, were largely mediated by these same domains of chronic stress. Likewise, the effects of life threat were largely mediated by all these domains plus ecological stress. A mediational model was not appropriate for understanding the consequences of property damage because it did not exhibit a main effect on psychological distress.  相似文献   
68.
A study was conducted with 225 college students to examine the effects of three organizational and policy variables on the perceived fairness and invasiveness of drug-testing practices. Specifically, the effects of warning type (no warning vs. advance warning), consequence of a positive drug test (termination vs. rehabilitation), and safety sensitivity of the job (safety sensitive vs. safety nonsensitive) were examined. Results suggested that specific features of the policy, as well as type of job under consideration, affected perceived invasiveness and fairness of drug testing. In general, testing was seen as more appropriate for safety-sensitive jobs, that is, those in which drug-impaired performance presented a high degree of danger for individuals. Although rehabilitation was perceived as more fair than termination, when safety was an issue, termination was viewed as a justifiable response by the company. Implications for organizational drug-testing policies are discussed.  相似文献   
69.
Three individuals with developmental disabilities were exposed to a series of assessment conditions to identify the source of reinforcement for their self-injurious behavior. In each case, self-injury occurred most often in instructional (demand) situations containing a brief time-out from the task contingent on self-injury, indicating that the behavior was an escape response (i.e., maintained by negative reinforcement). Treatment was implemented in a multiple baseline across subjects design and consisted of extinction (prevention of escape) plus instructional fading (initial elimination of instructions followed by their gradual reintroduction). Results showed that the combined treatment produced immediate and large reductions in self-injury that were maintained as the frequency of instructions was increased across sessions to match the original baseline rate of presentation. Results of a component analysis conducted with 1 subject suggested that stimulus fading accelerated the behavior-reducing effects of extinction.  相似文献   
70.
In this paper, we study the ability of a non-fluent aphasic patient, BN, to comprehend morphologically complex words when they appear in utterance contexts. We first establish that he is insensitive to the contextual appropriateness of both derived and inflected words. In a further experiment we show that he has no difficulty processing the stems of complex words and conclude that his problem is with the bound morphemes themselves. We then ask whether this problem is due to his inability to access either the phonological form of a morphologically complex word or its semantic and/or syntactic content. We find that only the access of semantic and syntactic content is impaired. We conclude from these six studies that: (a) BN presents a counter-example to the claim that non-fluent patients have particular difficulty with those aspects of morphology which have a syntactic function; (b) BN processes both derived and inflected words by mapping the sensory input onto the entire full-form of a complex word, but the semantic and syntactic content of the stem alone is accessed and integrated into the context. The semantic and syntactic implications of the suffix are never evaluated. This implies separate representation of the stems and suffixes of some types of morphologically complex words.  相似文献   
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