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51.
The authors explored the effect of Parkinson's disease (PD) on the generation and maintenance of response readiness in a simple reaction time task. They compared performance of idiopathic PD patients without dementia, age-matched controls, and younger controls over short (1-, 3-, and 6-s) and long (12- and 18-s) foreperiod intervals. After each trial, the authors probed memory for visual information that also had to be maintained during the trial interval. Patients and controls did not differ overall in their ability to maintain readiness over long delays. However, within the PD group only, errors in maintaining visual information were correlated with difficulty in maintaining readiness, suggesting that systems impaired in PD may facilitate the maintenance of processing in both motor and cognitive domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
Psychoanalysis today is largely a psychology of consciousness: Post- and neo-Freudians form a marginalized community within North America in comparison to contemporary relational and intersubjective theorists, who emphasize the phenomenology of lived conscious experience, dyadic attachments, affective attunement, social construction, and mutual recognition over the role of insight and interpretation. Despite the rich historical terrain of theoretical variation and advance, many contemporary approaches have displaced the primacy of the unconscious. Notwithstanding the theoretical hairsplitting that historically occurs across the psychoanalytic domain, one is beginning to see with increasing force and clarity what S. Mitchell and L. Aron (1999) referred to as the emergence of a new tradition, namely, relational psychoanalysis. Having its edifice in early object relations theory, the British middle school and American interpersonal traditions, and self psychology, relationality is billed as "a distinctly new tradition" (Mitchell & Aron, 1999, p. x). What is being labeled as the American middle group of psychoanalysis (C. Spezzano, 1997), relational and intersubjective theory have taken center stage. It may be argued, however, that contemporary relational and intersubjective perspectives have failed to be properly critiqued from within their own school of discourse. The scope of this article is largely preoccupied with tracing (a) the philosophical underpinnings of contemporary relational theory, (b) its theoretical relation to traditional psychoanalytic thought, (c) clinical implications for therapeutic practice, and (d) its intersection with points of consilience that emerge from these traditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
Results from 2 experimental studies suggest that self-protection and mate-search goals lead to the perception of functionally relevant emotional expressions in goal-relevant social targets. Activating a self-protection goal led participants to perceive greater anger in Black male faces (Study 1) and Arab faces (Study 2), both out-groups heuristically associated with physical threat. In Study 2, participants' level of implicit Arab-threat associations moderated this bias. Activating a mate-search goal led male, but not female, participants to perceive more sexual arousal in attractive opposite-sex targets (Study 1). Activating these goals did not influence perceptions of goal-irrelevant targets. Additionally, participants with chronic self-protective and mate-search goals exhibited similar biases. Findings are consistent with a functionalist, motivation-based account of interpersonal perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
This article had 2 aims: (a) to comprehensively review and synthesize the literature on predictors of health service utilization in survivors of traumatic events and posttraumatic stress disorder (PTSD) patients and (b) to discuss methodological issues in examining service utilization in this population. PsycINFO was searched for relevant articles published through April 2004. Included studies had to primarily sample trauma survivors or PTSD patients and statistically explore health service use determinants. Although some findings conflicted across studies, increased mental health service use was generally related to being female, having a previous trauma history, and having a PTSD diagnosis. Increased medical service use was found among those with a PTSD diagnosis. Methodological recommendations are made for future health service use studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
Creating and Rendering Convolution Surfaces   总被引:6,自引:0,他引:6  
Implicit surfaces obtained by convolution of multi-dimensional primitives with some potential function, are a generalisation of popular implicit surface models: blobs, metaballs and soft objects. These models differ in their choice of potential function but agree upon the use of underlying modelling primitives, namely, points. In this paper a method is described for modelling and rendering implicit surfaces built upon an expanded set of skeletal primitives: points, line segments, polygons, arcs and planes. An analytical solution to the convolution is described. This solution offers a more accurate and robust representation of the resultant implicit surface than previous methods. An algorithm for ray-tracing the surfaces formed through convolution of any combination of these primitives is also outlined.  相似文献   
56.
Building Large,Complex, Distributed Safety-Critical Operating Systems   总被引:4,自引:0,他引:4  
Wedde  Horst F.  Lind  Jon A. 《Real-Time Systems》1997,13(3):277-302
Safety-critical systems typically operate in unpredictable environments. Requirements for safety and reliability are in conflict with those for real-time responsiveness. Due to unpredictable environmental needs there is no static trade-off between measures to accommodate the conflicting objectives. Instead every feature or operating system service has to be adaptive. Finally, for any design problem, there cannot be any closed-form (formal) approach taking care at the same time of (external) time constraints or deadlines, and synchronization requirements in distributed design. The reason is that these two aspects are causally independent. - In this situation we worked out a heuristic experimental, performance-driven and performance-based methodology that allows in an educated way to start with a coarse system model, with accurate logical expectations regarding its behavior. Through experiments these expectations are validated. If they are found to successfully stand the tests extended expectations and model features are generated for refining the previous design as well as its performance criteria. The refinement is done in such a way that the previous experimental configurations are extreme model cases or data profiles which both logically and experimentally are to reproduce the behavior of the previous modeling step. Thus the novel performance aspects or tendencies could then unambiguously be attributed to the influences of the refined model features. We termed this methodology Incremental Experimentation. As a general methodology it relies on a principle of comparative performance studies rather than on realistic data for narrow application ranges. The paper describes how we applied a 5-step design and refinement procedure for developing, analyzing, and evaluating our distributed operating system MELODY that exhibits novel services for supporting real-time and safety-critical applications in unpredictable environments. Experimental set-ups and theme-related findings are discussed in particular.  相似文献   
57.
National traumatic events can produce extremely vivid memories. Using a questionnaire administered during telephone interviews, the authors investigated emotional responses to, and memory for. the September 11, 2001, terrorist attacks in patients with Alzheimer's disease (AD), patients with mild cognitive impairment (MCI), and healthy older adults in the initial weeks following the event and again 3-4 months later. There were several notable findings. First, patients with AD showed less memory than patients with MCI and older adults. Second, patients with AD, but not patients with MCI or older adults, appeared to retain more memory for personal versus factual information. Third, patients with AD and older adults did not differ in the intensity of their reported emotional responses to the attacks, whereas patients with MCI reported relatively less intense emotional responses. Last, distortions of memory for personal information were frequent for all participants but were more common in patients with AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
Williamson  Jon 《Minds and Machines》2004,14(4):539-549
The relationship between machine learning and the philosophy of science can be classed as a dynamic interaction: a mutually beneficial connection between two autonomous fields that changes direction over time. I discuss the nature of this interaction and give a case study highlighting interactions between research on Bayesian networks in machine learning and research on causality and probability in the philosophy of science.  相似文献   
59.
Conventional two-dimensional imaging of the trabecular meshwork (TM) provides limited information about the size, shape, and interconnection of the aqueous channels within the meshwork. Understanding the three-dimensional (3-D) relationships of the channels within this tissue may give insight into its normal function and possible changes present in the eye disease glaucoma. The purpose of our study was to compare laser scanning confocal microscopy with standard 1 μm Araldite-embeddedhistologic sections for 3-D analysis of the trabecular meshwork. In addition, the study was done to determine whether computerized 3-D reconstruction could isolate the fluid spaces of the trabecular meshwork and determine the size of interconnections between the fluid spaces. Confocal microscopy appears comparable to 1 μm Araldite-embedded tissue sections and has the advantage of inherent registration of the serial tissue sections. Three-dimensional reconstruction allowed the isolation of the fluid spaces within the trabecular meshwork and revealed the presence of numerous interconnections between larger fluid spaces. The distribution of these interconnections was randomly arranged, with no predilection for specific regions within the trabecular meshwork. This distribution of constrictions and “expansion chambers” may provide a clue to the mechanism by which subtle histologic changes are associated with increased ocular pressure in glaucoma.  相似文献   
60.
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