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171.
The relation of symptoms to cognitive dysfunction in schizophrenia is still controversial. This study was aimed (i) at verifying if a homogeneous sample of 10 young treated outpatients in remission from psychotic symptoms displays a characteristic pattern of cognitive dysfunction and (ii) at testing the issue of a general cognitive impairment. The neuropsychological performance of the patients was confronted with a large control group by means of Equivalent Scores, a normative method widely used in Italy, which allows direct, reliable comparison between tests and between patients. We found that our patients, as a group, were affected by a basic activation deficit in attention and by a semantic impairment. These deficits in symptom-free patients could indicate that their brains are in some ways working differently from those of normal controls and that this pattern is not necessarily linked to psychotic symptoms: their neuropsychological impairment might reflect a basic difference in the way of processing information that is always present and is independent of general intellectual decay.  相似文献   
172.
173.
The highly influential Baddeley and Hitch model of working memory (Baddeley & Hitch, 1974; see also Baddeley, 1986) posited analogical forms of representation that can be broadly characterized as sensorimotor, both for verbal and for visuospatial material. However, difficulties with the model of verbal working memory in particular have led investigators to develop alternative models that avoid appealing either to sensory coding or to motoric coding, or to both. This paper examines the evidence for sensorimotor coding in working memory, including evidence from neuropsychology and from sign language research, as well as from standard working memory paradigms, and concludes that only a sensorimotor model can accommodate the broad range of effects that characterize verbal working memory. In addition, several findings that have been considered to speak against sensorimotor involvement are reexamined and are argued to be in fact compatible with sensorimotor coding. These conclusions have broad implications, in that they support the emerging theoretical viewpoint of embodied cognition.  相似文献   
174.
Our current understanding into the role of stress in unexplained recurrent miscarriages comes from two different research strategies. The majority of research has examined the role of psychological support within this patient population. This support has been provided in a number of ways ranging from weekly interviews with a psychiatrist or gynaecologist and or visual re-assurance in the form of ultrasound scans. A comparison of psychological support with an absence of such intervention has found differences in successful pregnancy outcome varying from as great as 84 versus 26%, respectively. It has been assumed that psychological support reduces the miscarriage rate by reducing “stress”within this patient population. In addition it provides indirect support for a role of stress in the aetiology of unexplained recurrent miscarriage. Other studies have attempted to directly assess the effect of personality characteristics on miscarriage rate; these studies have yielded conflicting results.The mechanism by which stress may be causal in the aetiology of unexplained recurrent miscarriage has not been examined in humans. Animal studies, however, have found that psychological distress can alter immune parameters that may be intricately involved with implantation. These parameters include an elevation of the “abortive” cytokine TNF-a and a reduction in the “anti-abortive” cytokine TGF-P2. Cells that are involved in the release of TNF-a at the feto-maternal interface include T cells, macrophages and mast cells.Mechanisms through which stress may act on these cells are explored and an integrated model is postulated.  相似文献   
175.
M.亨利分析了经典现象学的意向性概念的理论内涵和问题,特别指出意向性在以"出离"的方式理解显现的自我显现时所遇到的悖谬。同时,他指出,由于胡塞尔的意向性现象学以"出离"的、可见的意向性方式理解生命,从而生命在他那里被遗忘和隐匿。生命的自我显现,以一种不同于可见的、分离的意向性方式来实现,这是一种生命的现象学。这是未来的非意向性现象学的任务。  相似文献   
176.
论复合平等   总被引:1,自引:0,他引:1  
分配的正义是一个宽广的观念。它把整个物品(goods)的世界都置于哲学反思的领域之内。没有什么会被忽略;我们公共生活的每一个特征都会被考察到。人类社会就是一个进行分配的社群。人类社会不全是分配的社会,但却主要是一个分配的社会:我们在一起共有(share)、划分(divide)和交换(exchange)。我们同样在一起制造那些我们所共有、划分和交换的事物;而制造——也就是工作——是通过劳动的划分而在我们中间分配的。我在经济中的处境,我在政治秩序中的地位,我在同侪中的声誉,我的物质的所有物:所有这些都自他人而来,到我这里。说我是正确地还是错误地、正义地还是不正义地拥有我所拥有的事物是可能的;但是给定分配的范围和参与者的人数,要作出这样的判断决不是轻易的。  相似文献   
177.
Pigeons were trained on a multiple schedule in which each component consisted of concurrent variable-interval (VI) 30-s VI 60-s schedules. The two components of the multiple schedule differed only in terms of the changeover delays (COD): For one component short CODs were employed, and in the second component long CODs were used. After approximate matching was obtained in each component, probe tests involving new combinations of stimuli were presented (e.g., the VI 30-s schedule from each component) to determine how the different CODs affected preference. Despite shorter CODs producing higher changeover rates, the COD value had no systematic effect on preference on the probe trials. However, differences in reinforcement rate always produced preference for the schedule with the higher reinforcement rate. The results thus show that the the pattern of changeover behavior per se is not a critical determinant of choice in the probe-trial procedure.  相似文献   
178.
To investigate the nature of the frames of reference used to control an arm movement aimed at a visual target, we studied the accuracy of movements differing by the initial arm and eye positions. The results support the assumption that in darkness target location is internally represented in an egocentric frame of reference. Furthermore, when movements carried out with and without eye saccade are compared, it appears that foveating the target changes the reference used to generate the reaching arm movements, that is, the oculocentric reference is replaced by a head-trunk reference. An explanation for this phenomenon could be that a steady body-related landmark is needed to insure stable registering of the target location in the surrounding space, despite displacement of the body segments with respect to one another.  相似文献   
179.
维特根斯坦在第一次世界大战的战壕中写完他的第一本书——《逻辑哲学论》,当时他在奥地利军队中服役.一系列精雕细刻的格言由一个复杂的排列体系联结起来,并且一切都按照从形而上学到形式逻辑的方向排列.此书被罗素誉为是一部杰作.人们很快就广泛认识到这本书的重要性,特别是通过石里克、卡纳普和魏斯曼,维也纳学派认识到了它的重要性.《逻辑哲学论》立刻使维特根斯坦在哲学家的神殿中占有了一席之地.《逻辑哲学论》是维特根斯坦自己出版的唯一的一本书.有一段时间他放弃哲学去当了一名小学教师,后来又在奥地利做一名建筑师,1929年他回到剑桥,在那里断断续续地工作一直到他1951年去世.他的思想交流实际上仅局限于课堂,他在由学生和同事组成的非常亲密的  相似文献   
180.
We examined the semantic impairment for natural kinds in patients with probable Alzheimer's disease (AD) and semantic dementia (SD) using an inductive reasoning paradigm. To learn about the relationships between natural kind exemplars and how these are distinguished from manufactured artifacts, subjects judged the strength of arguments such as "Humans have a chemical called sebum. Therefore, frogs have a chemical called sebum." These judgments depend on subjects' perception of the similarity between the familiar objects named in the premise and the conclusion. Controls rated arguments generalizing from a natural kind to an artifact as significantly weaker than arguments generalizing from one natural kind to another natural kind. SD patients demonstrated a graded profile of generalization without evidence of a categorical distinction between natural kinds and artifacts. AD patients' judgments also suggested more difficulty than controls at distinguishing between natural kinds and artifacts. Both SD patients and AD patients resembled controls in their judgments of arguments where both objects are from the natural kinds category. Semantic knowledge thus appears to be sufficiently preserved in both AD and SD to support within-category similarity judgments. We suggest that SD patients may be impaired in part at identifying the features critical to diagnosing membership in a semantic category, while AD patients' performance is consistent with their semantic categorization deficit.  相似文献   
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