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Throughout the past century, assimilation has been the hegemonic theory of ethnic group relations in sociology, and Robert E. Park is generally considered to be the key figure associated with the articulation of assimilation's canonical formulation. Based on a careful reading of Park's main essays on assimilation, this article argues that those who associate his position with the melting pot (with its assumption of the eradication of ethnic traits and ties), the race-relations cycle, or a straight-line process of incorporation misconstrue his views. This article is in part corrective and in part revisionist insofar as it is intended to indicate aspects of Park's theory that have particular relevance to current sociological efforts to understand the implications of assimilation in multiethnic liberal democracies.  相似文献   

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Object substitution masking (OSM) is said to occur when a perceptual object is hypothesized that is mismatched by subsequent sensory evidence, leading to a new hypothesized object being substituted for the first. For example, when a brief target is accompanied by a longer lasting display of nonoverlapping mask elements, reporting of target features may be impaired. J. T. Enns and V. Di Lollo (2000) considered it an outstanding question whether OSM masks some or all aspects of a target. The authors report three experiments demonstrating that OSM can selectively affect target features. Participants may be able to detect a target while being unable to report other aspects of it or to report the color but not the orientation of a target (or vice versa). We discuss these findings in relation to two other visual phenomena.  相似文献   

4.
Categorization studies have focused on the importance of a variety of perceptual properties (shape, size, weight). The present study explored whether the softness or hardness of an object might influence the way we categorize and consider category members. Of additional interest was whether information on consistence is automatically activated and whether it is modulated by the kind of task and of response modality. Three experiments demonstrated that information on consistence is automatically activated, and it helps us to distinguish between artefacts and natural objects. Interestingly, the results are in agreement with the simulation hypothesis; namely, when we consider artefacts, we simulate using them and information on their consistence is activated; this simulation is modulated by the task. The way we differently process artefacts and natural objects across the experiments confirms the simulation hypothesis and our sensitivity to the response modality.  相似文献   

5.
Scholl BJ  Pylyshyn ZW  Feldman J 《Cognition》2001,80(1-2):159-177
The notion that visual attention can operate over visual objects in addition to spatial locations has recently received much empirical support, but there has been relatively little empirical consideration of what can count as an 'object' in the first place. We have investigated this question in the context of the multiple object tracking paradigm, in which subjects must track a number of independently and unpredictably moving identical items in a field of identical distractors. What types of feature clusters can be tracked in this manner? In other words, what counts as an 'object' in this task? We investigated this question with a technique we call target merging: we alter tracking displays so that distinct target and distractor locations appear perceptually to be parts of the same object by merging pairs of items (one target with one distractor) in various ways - for example, by connecting item locations with a simple line segment, by drawing the convex hull of the two items, and so forth. The data show that target merging makes the tracking task far more difficult to varying degrees depending on exactly how the items are merged. The effect is perceptually salient, involving in some conditions a total destruction of subjects' capacity to track multiple items. These studies provide strong evidence for the object-based nature of tracking, confirming that in some contexts attention must be allocated to objects rather than arbitrary collections of features. In addition, the results begin to reveal the types of spatially organized scene components that can be independently attended as a function of properties such as connectedness, part structure, and other types of perceptual grouping.  相似文献   

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Various forms of category-specificity have been described at both the cognitive and neural levels, inviting the inference that different semantic domains are processed by distinct, dedicated mechanisms. In this paper, we argue for an extension of a domain-specific interpretation to these phenomena that is based on network-level analyses of functional coupling among brain regions. On this view, domain-specificity in one region of the brain emerges because of innate connectivity with a network of regions that also process information about that domain. Recent findings are reviewed that converge with this framework, and a new direction is outlined for understanding the neural principles that shape the organization of conceptual knowledge.  相似文献   

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Six experiments were conducted to investigate the nature of the contents of object files, temporary representations that store information about objects. Experiment 1 used a lexical priming paradigm with a lexical decision task, in which the prime and target could appear in either the same or different locations. The results indicated a greater priming effect when the prime and target appeared in the same location than when they appeared in different locations (object- or location-specific priming). Experiment 2 replicated these findings for objects that changed position during the display. Experiment 3 demonstrated that these findings reflected the inclusion of abstract identity information, rather than physical form, in object files. Three additional experiments tested for the presence of three types of semantic information (related concepts, semantic features, and category membership) in object files. No object-specific priming effects were found. Taken together, these experiments suggest that an object file includes identity information, but not semantic information. Implications of the results for object file theory are discussed.  相似文献   

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A new paradigm is proposed that involves a simple judgment on an object’s perceptual feature that is independent of object identity. Subjects were required to categorize as vertical or horizontal the main axis of elongation of an object picture. Both fake and real-world objects were presented, and a graphical manipulation was applied to their shapes so that the canonical elongation of the real-world objects was incongruent with the elongation of their shapes after the manipulation. The results showed an influence of the identity of the objects on the perceptual task in the form of a cost in judging the elongation of the incongruent real-world objects. The results are taken as evidence for automatic activation of objects’ stored representations. A “horse-race” model of the influence of these representations on the perceptual task is proposed in the final section of the article.  相似文献   

9.
Infants have a bandwidth-limited object working memory (WM) that can both individuate and identify objects in a scene, (answering ‘how many?’ or ‘what?’, respectively). Studies of infants’ WM for objects have typically looked for limits on either ‘how many’ or ‘what’, yielding different estimates of infant capacity. Infants can keep track of about three individuals (regardless of identity), but appear to be much more limited in the number of specific identities they can recall. Why are the limits on ‘how many’ and ‘what’ different? Are the limits entirely separate, do they interact, or are they simply two different aspects of the same underlying limit?We sought to unravel these limits in a series of experiments which tested 9- and 12-month-olds’ WM for object identities under varying degrees of difficulty. In a violation-of-expectation looking-time task, we hid objects one at a time behind separate screens, and then probed infants’ WM for the shape identity of the penultimate object in the sequence. We manipulated the difficulty of the task by varying both the number of objects in hiding locations and the number of means by which infants could detect a shape change to the probed object. We found that 9-month-olds’ WM for identities was limited by the number of hiding locations: when the probed object was one of two objects hidden (one in each of two locations), 9-month-olds succeeded, and they did so even though they were given only one means to detect the change. However, when the probed object was one of three objects hidden (one in each of three locations), they failed, even when they were given two means to detect the shape change. Twelve-month-olds, by contrast, succeeded at the most difficult task level.Results show that WM for ‘how many’ and for ‘what’ are not entirely separate. Individuated objects are tracked relatively cheaply. Maintaining bindings between indexed objects and identifying featural information incurs a greater attentional/memory cost. This cost reduces with development. We conclude that infant WM supports a small number of featureless object representations that index the current locations of objects. These can have featural information bound to them, but only at substantial cost.  相似文献   

10.
According to a common view of human agency, desires determine at least some of the ends that agents set for themselves. In this paper, I argue that this view is false. I show that without reason’s ability to determine the means to an end it is impossible to determine ends. Furthermore, even when an end is determined in light of a desire, only reason can make sense of the distinction between an end and merely a means to that end. In fact, in many cases the end which is determined in light of desires is to remove these desires, rather than to “serve and obey” them. Hence, reason is necessary for determining our ends, and thus explaining the teleological aspect of agency.  相似文献   

11.
Sleep onset is associated with marked changes in behavioral, physiological, and subjective phenomena. In daily life though subjective experience is the main criterion in terms of which we identify it. But very few studies have focused on these experiences. This study seeks to identify the subjective variables that reflect sleep onset. Twenty young subjects took an afternoon nap in the laboratory while polysomnographic recordings were made. They were awakened four times in order to assess subjective experiences that correlate with the (1) appearance of slow eye movement, (2) initiation of stage 1 sleep, (3) initiation of stage 2 sleep, and (4) 5 min after the start of stage 2 sleep. A logistic regression identified control over and logic of thought as the two variables that predict the perception of having fallen asleep. For sleep perception, these two variables accurately classified 91.7% of the cases; for the waking state, 84.1%.  相似文献   

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Six experiments using habituation of exploratory behavior tested whether disoriented rats foraging in a large arena encode the shapes of arrays of objects. Rats did not respond to changes in position of a single object, but they responded to a change in object color and to a change in position of 1 object in a square array, as in previous research (e.g., C. Thinus-Blanc et al., 1987). Rats also responded to an expansion of a square array, suggesting that they encoded sets of interobject distances rather than overall shape. In Experiments 4-6, rats did not respond to changes in sense of a triangular array that maintained interobject distances and angles. Shapes of object arrays are encoded differently from shapes of enclosures.  相似文献   

13.
The particular problem of recognition from unusual viewpoints, may well involve a substantial problem-solving component and employ frontal/central executive resources. The present study investigates this question using a dual-task technique. In Experiment 1, the reliability of an unusual views effect was demonstrated. Experiment 2 showed that a central executive secondary task selectively disrupts unusual views recognition. These results are discussed in the context of existing lesion and functional imaging findings.  相似文献   

14.
Diagnostic reasoning, defined as the ability to infer unobserved causes based on the observation of their effects, is a central cognitive competency of humans. Yet, little is known about diagnostic reasoning in non-human primates, and what we know is largely restricted to the Great Apes. To track the evolutionary history of these skills within primates, we investigated long-tailed macaques’ understanding of the significance of inclinations of covers of hidden food as diagnostic indicators for the presence of an object located underneath. Subjects were confronted with choices between different objects that might cover food items. Based on their physical characteristics, the shape and orientation of the covers did or did not reveal the location of a hidden reward. For instance, hiding the reward under a solid board led to its inclination, whereas a hollow cup remained unaltered. Thus, the type of cover and the occurrence or absence of a change in their appearance could potentially be used to reason diagnostically about the location of the reward. In several experiments, the macaques were confronted with a varying number of covers and their performance was dependent on the level of complexity and on the type of change of the covers’ orientation. The macaques could use a board’s inclination to detect the reward, but failed to do so if the lack of inclination was indicative of an alternative hiding place. We suggest that the monkeys’ performance is based on a rudimentary understanding of causality, but find no good evidence for sophisticated diagnostic reasoning in this particular domain.  相似文献   

15.
The authors studied 2 patients, S.M. and R.N., to examine perceptual organization and its relationship to object recognition. Both patients had normal, low-level vision and performed simple grouping operations normally but were unable to apprehend a multielement stimulus as a whole. R.N. failed to derive global structure even under optimal stimulus conditions, was less sensitive to grouping by closure, and was more impaired in object recognition than S.M. These findings suggest that perceptual organization involves a multiplicity of processes, some of which are simpler and are instantiated in lower order areas of visual cortex (e.g., collinearity). Other processes are more complex and rely on higher order visual areas (e.g., closure and shape formation). The failure to exploit these latter configural processes adversely affects object recognition.  相似文献   

16.
Decades of research and debate on the origins of object permanence in infancy have contrasted various types of learning with possible innate contributions. A recent paper by Johnson et al. adds a new perspective to this debate by reporting that even very brief training periods can dramatically influence infants' persisting object representations. Such training studies have the potential to constrain 'nature versus nurture' debates in novel ways, although important challenges remain.  相似文献   

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Abstract

The concept of countertransference as a robust cornerstone of psychoanalytic work has gained momentum over the last five decades. It is a prime example of elastic concepts covering the range from microprocesses to global clinical phenomena. Empirical research on the treatment process has for a long time – and for good reasons – avoided even trying to measure countertransference. We report here on various efforts for approaching a methodology for measuring it. The paper organizes the various approaches in terms of stages of research.  相似文献   

19.
Previous research has shown that 5-month-old infants visually anticipate a moving object's appearance after it disappears behind a screen. This experiment assesses the underlying basis for such anticipatory tracking. Three tracking tasks were presented to 5- and 9-month-old infants. In the Permanence task, the object's continuous existence was apparently violated while it was behind a screen. In the Feature and Trajectory tasks, the object's features or trajectory changed while behind the screen. Disruptions in the infant's smooth visual pursuit of the object were recorded. Five-mont-olds showed disruptions of visual tracking in the Feature and Trajectory tasks, but not in the Permanence task. The tracking of the 9-month-olds was disrupted in all three tasks. We conclude that both 5- and 9-month-olds possess rules specifying the identity of a moving object which is occluded. For 5-month-olds these rules are based upon the object's features and trajectory, but not upon a concept of object permanence. For 9-month-olds all three rules—feature, trajectory, and permanence—are utilized in visual tracking.  相似文献   

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