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1.
Visual motion and the human brain: what has neuroimaging told us?   总被引:8,自引:0,他引:8  
Recently, neuroimaging techniques have been applied to the study of human motion perception, complementing established techniques such as psychophysics, neurophysiology and neuropsychology. Because vision, particularly motion perception, has been studied relatively extensively, it provides an interesting case study to examine the contributions and limitations of neuroimaging to cognitive neuroscience. We suggest that in the domain of motion perception neuroimaging has: (1) revealed an extensive network of motion areas throughout the human brain, in addition to the well-studied motion complex (MT+); (2) verified and extended findings from other techniques; (3) suggested extensive top-down influences on motion perception; and (4) allowed experimenters to examine the neural correlates of awareness. We discuss these contributions, along with limitations and future directions for the neuroimaging of motion.  相似文献   

2.
The "Global Precedence Effect" (GPE) is a well-established phenomenon characterised by a global advantage (global response times that are faster than local response times) and an interference effect from global distractors during identification of local targets but not vice versa. In the present study, two experiments were carried out to examine how the GPE is affected by the meaningfulness of the stimuli. Using global/local compound stimuli based on either meaningful or meaningless stimuli, we found, on the one hand, that the global level was always processed faster than the local level, irrespective of the meaningfulness of the material. On the other hand, results show that the interference effect occurred only with meaningful stimuli. We propose that automatic identification of meaningful stimuli plays a role in the interference effect. These results suggest that the GPE involves both "sensory mechanisms" (responsible for the global advantage) and "cognitive mechanisms" (responsible for the interference effect).  相似文献   

3.
In Vytal and Hamann (2010) we reported a neuroimaging meta-analysis that found that basic emotions can be distinguished by their brain activation correlates, in marked contrast to Lindquist et al.'s conclusions in the target article. Here, I discuss implications of these findings for understanding emotion, outline limitations of using meta-analyses and neuroimaging as the sole basis for deciding between emotion views, and suggest that these views are essentially compatible and could be adapted and combined into an integrated emotion framework.  相似文献   

4.
Although the majority of research in visual word recognition has targeted single-syllable words, most words are polysyllabic. These words engender special challenges, one of which concerns their analysis into smaller units. According to a recent hypothesis, the organization of letters into groups of successive consonants (C) and vowels (V) constrains the orthographic structure of printed words. So far, evidence has been reported only in French with factorial studies of relatively small sets of items. In the present study, we performed regression analyses on corpora of megastudies (English and British Lexicon Project databases) to examine the influence of the CV pattern in English. We compared hiatus words, which present a mismatch between the number of syllables and the number of groups of adjacent vowel letters (e.g., client), to other words, controlling for standard lexical variables. In speeded pronunciation, hiatus words were processed more slowly than control words, and the effect was stronger in low-frequency words. In the lexical decision task, the interference effect of hiatus in low-frequency words was balanced by a facilitatory effect in high-frequency words. Taken together, the results support the hypothesis that the configuration of consonant and vowel letters influences the processing of polysyllabic words in English.  相似文献   

5.
This article discusses the relation between features of empirical data and structures in the world. I defend the following claims. Any empirical data set exhibits all possible patterns, each with a certain noise term. The magnitude and other properties of this noise term are irrelevant to the evidential status of a pattern: all patterns exhibited in empirical data constitute evidence of structures in the world. Furthermore, distinct patterns constitute evidence of distinct structures in the world. It follows that the world must be regarded as containing all possible structures. The remainder of the article is devoted to elucidating the meaning and implications of the latter claim.  相似文献   

6.
Results of five studies show that during the second half of the twentieth century there were increases in the Development Quotients (DQs) of infants in the first two years of life. These gains were obtained for the Bayley Scales in the United States and Australia, and for the Griffiths Test in Britain. The average of 19 data points is a DQ gain of approximately 3.7 DQ points per decade. Similar gains of approximately 3.9 IQ points per decade have been present among preschool children aged 4–6 years. These gains are about the same as the IQ gains of school age students and adults on the Wechsler and Binet tests. This suggests that the same factor has been responsible for all these secular gains. This rules out improvements in education, greater test sophistication, etc. and most of the other factors that have been proposed to explain the Flynn effect. It is proposed that the most probable factor has been improvements in pre-natal and early post-natal nutrition.  相似文献   

7.
Contextual therapy is a heuristic approach to intergenerational family dynamics. This article sets forth the main tenets of that approach and explores the contribution that it makes to the pastoral care and counseling of families. The concept of relational justice, which is a focal point in contextual therapy, is brought into dialogue with the biblical concept of righteousness and the theological concept of justification by faith.  相似文献   

8.
What does the occluding contour tell us about solid shape?   总被引:5,自引:0,他引:5  
J J Koenderink 《Perception》1984,13(3):321-330
A new theorem is discussed that relates the apparent curvature of the occluding contour of a visual shape to the intrinsic curvature of the surface and the radial curvature. This theorem allows the formulation of general laws for the apparent curvature, independent of viewing distance and regardless of the fact that the rim (the boundary between the visible and invisible parts of the object) is a general, thus twisted, space curve. Consequently convexities, concavities, or inflextions of contours in the retinal image allow the observer to draw inferences about local surface geometry with certainty. These results appear to be counterintuitive, witness to the treatment of the problem by recent authors. It is demonstrated how well-known examples, used to show how concavities and convexities of the contour have no obvious relation to solid shape, are actually good illustrations of the fact that convexities are due to local ovoid shapes, concavities to local saddle shapes.  相似文献   

9.
A reassessment of category-specific semantic deficits in light of their contribution to a theory of the representation of lexical concepts is proposed. Two theories are examined: one, held by the majority of researchers in the field, claims that concepts are represented by sets of features; another, in contrast, claims that concepts are atomic representations. An analysis of category-specific semantic deficits in terms of inferential relations (of the meaning-postulates type) between atomic concepts is elaborated. It is argued that this theory can better account for the pattern of performance exhibited by patients with semantic deficits.  相似文献   

10.
Robert Nozick’s experience machine thought experiment is often considered a decisive refutation of hedonism. I argue that the conclusions we draw from Nozick’s thought experiment ought to be informed by considerations concerning the operation of our intuitions about value. First, I argue that, in order to show that practical hedonistic reasons are not causing our negative reaction to the experience machine, we must not merely stipulate their irrelevance (since our intuitions are not always responsive to stipulation) but fill in the concrete details that would make them irrelevant. If we do this, we may see our feelings about the experience machine becoming less negative. Second, I argue that, even if our feelings about the experience machine do not perfectly track hedonistic reasons, there are various reasons to doubt the reliability of our anti-hedonistic intuitions. And finally, I argue that, since in the actual world seeing certain things besides pleasure as ends in themselves may best serve hedonistic ends, hedonism may justify our taking these other things to be intrinsically valuable, thus again making the existence of our seemingly anti-hedonistic intuitions far from straightforward evidence for the falsity of hedonism.  相似文献   

11.
12.
We examined the development of magnitude representations in children (Exp 1: kindergartners, first-, second- and sixth graders, Exp 2: kindergartners, first-, second- and third graders) using a numerical same-different task with symbolic (i.e. digits) and non-symbolic (i.e. arrays of dots) stimuli. We investigated whether judgments in a same-different task with digits are based upon the numerical value or upon the physical similarity of the digits. In addition, we investigated whether the numerical distance effect decreases with increasing age. Finally, we examined whether the performance in this task is related to general mathematics achievement. Our results reveal that a same-different task with digits is not an appropriate task to study magnitude representations, because already late kindergarteners base their responses on the physical similarity instead of the numerical value of the digits. When decisions cannot be made on the basis of physical similarity, a similar numerical distance effect is present over all age groups. This suggests that the magnitude representation is stable from late kindergarten onwards. The size of the numerical distance effect was not related to mathematical achievement. However, children with a poorer mathematics achievement score seemed to have more difficulties to link a symbol with its corresponding magnitude.  相似文献   

13.
The article begins with a summary of eight well-substantiated conclusions drawn from research on perception in infants that have implications for theories of perception. The following section examines several traditional and modern theories of perception in the light of these conclusions. Finally, some "big issues" that have divided perceptual and cognitive theories are discussed, with the suggestion that research on infants can help reconcile the divided camps. Research on perception in young infants not only flourishes but also presents a challenge to all theories of perception.  相似文献   

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16.
This article explores the significance of the Fresh Expressions movement in the UK since the ground‐breaking Mission‐Shaped Church report was published by the Church of England in 2004. After reviewing the background to this report, the article explores some of the report's central themes and examines some of the more recent research on the movement's impact in the UK. It then highlights six ways in which fresh expressions continue to be significant as a missionary response in a post‐Christian context. These include the movement's theological underpinnings, its reassessment of key questions in ecclesiology, its commitment to local and contextual mission, and the emergence of a predominantly lay leadership. In recognizing that the movement is still in a state of evolution, the article concludes by suggesting some areas of continuing debate and challenge for the future.  相似文献   

17.
18.
Evaluative conditioning (EC) refers to the effect that pairings of a conditioned stimulus (CS) with a valenced unconditioned stimulus (US) lead to changes in the evaluation of the CS. There have been recurring debates about whether EC requires awareness of the contingency between CSs and USs during learning. We argue that the memory performance data obtained in the standard paradigm remain ambiguous about the role of contingency awareness during the encoding of CS–US pairings. First, memory performance data are unable to distinguish between encoding-related versus retrieval-related effects. Second, the relation between memory performance and evaluation is correlational, which limits conclusions about causal relations between memory performance and EC effects. These ambiguities imply that any possible data pattern can be interpreted in at least two different ways. It is concluded that a resolution of the current debate requires alternative approaches in which contingency awareness is experimentally manipulated during the encoding of CS–US pairings.  相似文献   

19.
The purpose of this article is to show how schizophrenia, understood as a distortion of the most intimate structures of subjectivity, illustrates the nature of subjectivity as such, while at the same time how philosophical considerations may help to understand schizophrenia. More precisely, schizophrenic experiences of self-alienation seem to reflect a congealing or concretization of a form of differentiation or potential alterity implicit in the dynamic nature of subjectivity. In other words, we propose that the structure of subjectivity includes potential divisions and fissures that condition the experiences of radical self-alienation seen in schizophrenia. In order to elucidate how this alterity emerges within the self in schizophrenia and in order to consider its conditions of possibility we examine the disorders of the self as described in phenomenological psychopathology. We especially use the work of the Japanese psychiatrists Mari Nagai, her teacher Bin Kimura, and the French psychiatrist Henry Ey, supplemented with clinical material from our own research. Finally, we shed light on the development of the psychotic symptoms such as hallucinations and delusions, which are understood as the expressions of a radical alterization (i.e., becoming other) of the self.  相似文献   

20.
This paper argues that understanding developmental disorders requires developing theories and models that explicitly represent the role of general intelligence in the cognitive phenotype of the disorder. In the case of autism it is argued that the low-IQ scores of people with autism are not likely to be due to a deficit in the cognitive process that is arguably the major cause of mental retardation - namely, speed of processing - but rather low IQ reflects the pervasive and cascading effects of the deficit in the information-processing module that causes autism. In the case of dyslexia, two radically different models of reading disorder (ability = disability and a modular deficit model) are likely to be influenced by the effect of general intelligence on reading performance in ways that will remain unclear without an explicit model of how general intelligence influences reading.  相似文献   

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