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Voluntary shifts of attention are often motivated in experimental contexts by using well-known symbols that accurately predict the direction of targets. The authors report 3 experiments, which showed that the presentation of predictive spatial information does not provide sufficient incentive to elicit voluntary shifts of attention. For instance, when allowed to spontaneously choose between using a 100%-valid spatial word cue versus searching without the aid of the cue, observers consistently searched for a unique target without the aid of the cue. Another experiment showed that observers' choice to use spatial word cues could be biased by providing dedicated time to process the cue before the target display appeared (i.e., nonzero, cue-target SOAs). Although this dedicated processing time has routinely been included in spatial cuing experiments, its incentive-inducing role has never been acknowledged. Implications for theories of both voluntary and involuntary control are discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   

3.
Nonspatial attentional shifts between audition and vision   总被引:2,自引:0,他引:2  
This study investigated nonspatial shifts of attention between visual and auditory modalities. The authors provide evidence that the modality of a stimulus (S1) affected the processing of a subsequent stimulus (S2) depending on whether they shared the same modality. For both vision and audition, the onset of S1 summoned attention exogenously to its modality, causing a delay in processing S2 in a different modality. That undermines the notion that auditory stimuli have a stronger and more automatic alerting effect than visual stimuli (M. I. Posner, M. J. Nissen, & R. M. Klein, 1976). The results are consistent with other recent studies showing cross-modal attentional limitation. The authors suggest that such cross-modal limitation can be produced by simply presenting S1 and S2 in different modalities and that central processing mechanisms are also, at least partially, modality dependent.  相似文献   

4.
Animals trained on 2 discriminations learn the 2nd rapidly if the relevant stimuli are from the same dimension as the 1st (an intradimensional or ID shift) but slowly if the relevant stimuli for the 2 problems are from different dimensions (an extradimensional or ED shift). Four experiments examined ID and ED shifts in spatial learning. Rats trained on 2 spatial problems learned the 2nd more rapidly than rats whose 1st problem had been nonspatial. But this difference between ID and ED shifts depended on the spatial relationship between rewarded (S+) and unrewarded (S-) alternatives in the 2 spatial problems. The results imply that rats trained on a spatial discrimination do not learn to attend to all spatial landmarks but only to those that serve to differentiate S+ and S-.  相似文献   

5.
The original impulse for using computers in a laboratory dedicated to spatial vision research and the current role of computers in experiments are detailed. Although computers are used widely for modeling spatial vision, there is some doubt about whether conventional serial computers are the most appropriate tools for this task.  相似文献   

6.
This study examined factors related to mental illness in children and adolescents. A survey of all 362 files of child and adolescent patients discharged from a single residential treatment facility in 1961-1962, 1971-1972, and 1978 revealed several major diagnostic trends. The proportion of cases diagnosed as schizophrenic decreased by one-third, those diagnosed as neurotic increased over ten-fold, and significant increases occurred in the proportion of children diagnosed as autistic, personality disorder, and behavior disorder of childhood and adolescence. There was a decrease in cases between 6 and 12 years of age and a significant increase in 13- to 18-year-olds. The relative importance of symptoms appeared to be interpreted differently at various times. Significant changes were also found In treatment length, in medications used, and in a number of factors related to the characteristics of the family.  相似文献   

7.
Previous research on reasoning about spatial arrangements has revealed two major strategies used by adults: Series Formation and Elimination. It was hypothesized that all adults have both strategies available. An experiment was carried out in which subjects who showed no spontaneous tendency to shift strategy were induced to do so. The strategy shifts by the subjects are simulated by a computer program in the form of a homogeneous production system. The conditions under which homogeneous and hierarchical production system models will yield the same predictions are discussed.  相似文献   

8.
Near-death studies can be viewed within a theoretical framework of paradigms and paradigm shifts as explicated by Thomas Kuhn (1962). Assuming the validity of Kuhn's model, I hypothesize that the paradigm of today's normal science is shifting to a new paradigm to accommodate data from near-death studies.  相似文献   

9.
Neurologically normal observers misperceive the midpoint of horizontal lines as systematically leftward of veridical center, a phenomenon known as pseudoneglect. Pseudoneglect is attributed to a tonic asymmetry of visuospatial attention favoring left hemispace. Whereas visuospatial attention is biased toward left hemispace, some evidence suggests that audiospatial attention may possess a right hemispatial bias. If spatial attention is supramodal, then the leftward bias observed in visual line bisection should also be expressed in auditory bisection tasks. If spatial attention is modality specific then bisection errors in visual and auditory spatial judgments are potentially dissociable. Subjects performed a bisection task for spatial intervals defined by auditory stimuli, as well as a tachistoscopic visual line bisection task. Subjects showed a significant leftward bias in the visual line bisection task and a significant rightward bias in the auditory interval bisection task. Performance across both tasks was, however, significantly positively correlated. These results imply the existence of both modality specific and supramodal attentional mechanisms where visuospatial attention has a prepotent leftward vector and audiospatial attention has a prepotent rightward vector of attention. In addition, the biases of both visuospatial and audiospatial attention are correlated.  相似文献   

10.
Perception of spatial order in central and extrafoveal vision was investigated by means of a task in which observers judged the relative position of a target line segment in a briefly flashed array of six line segments. The line arrays were size-scaled in extrafoveal vision according to the cortical magnification factor derived from the cone and ganglion cell distributions across the human retina, i.e. the stimulus representations in the striate cortex were of equal size in central and eccentric vision. In central vision, observers could judge the relative position of the target with high accuracy but in extrafoveal vision the task was more difficult, especially with short interline distances. However, performance was well above chance level also in extrafoveal vision.  相似文献   

11.
Performance was examined in a task requiring the reconstruction of spatial locations. Previous research suggests that it may be necessary to differentiate between memory for smaller and larger numbers of locations (Postma & DeHaan, 1996), at least when locations are presented simultaneously (Igel & Harvey, 1991). Detailed analyses of the characteristics of performance showed that such a differentiation might also be required for sequential presentation. Furthermore the slope of the function relating each successive response to accuracy was greater with 3 than with 6, 8, or 10 locations that did not differ. Participants also reconstructed the arrays as being more proximal than in fact they were; sequential presentation eliminated this distortion when there were three but not when there were more than three locations. These results support the idea that very small numbers of locations are remembered using a specific form of representation, which is unavailable to larger numbers of locations.  相似文献   

12.
Aging and shifts of visual spatial attention.   总被引:2,自引:0,他引:2  
Three experiments examined adult age differences in the efficiency of endogenous (voluntary) and exogenous (involuntary) attention shifts. Younger and older subjects performed a spatial cuing task in which abruptly onset peripheral cues (Experiment 1) or central, symbolic cues (Experiments 2 and 3) were presented before a target stimulus at intervals ranging from 50 to 250 ms. With peripheral cues, the magnitude of cuing effects was at least as great for older as for younger adults and followed a similar time course. Similar results were obtained with symbolic cues, although cuing effects for older adults varied with cue difficulty. The results suggest that cue encoding may decline with advancing age but that the efficiency of the shift process is preserved.  相似文献   

13.
Orientation specificity and spatial selectivity in human vision   总被引:1,自引:0,他引:1  
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14.
Attention, Perception, & Psychophysics - In previous studies of selective attention using the Sperling partial-report paradigm, the selection criterion has been confounded with the spatial...  相似文献   

15.
A developmental cascade model linking competence and symptoms was tested in a study of a normative, urban school sample of 205 children (initially 8 to 12 years old). Internalizing and externalizing symptoms and academic competence were assessed by multiple methods at the study outset and after 7, 10, and 20 years. A series of nested cascade models was tested through structural equation modeling. The final model indicated 2 hypothesized cascade effects: Externalizing problems evident in childhood appeared to undermine academic competence by adolescence, which subsequently showed a negative effect on internalizing problems in young adulthood. A significant exploratory effect was consistent with internalizing symptoms containing or lowering the net risk for externalizing problems under some conditions. These 3 cascade effects did not differ by gender and were not attributable to effects of IQ, parenting quality, or socioeconomic differences. Implications are discussed for developmental models of cascades, progressions, and preventive interventions.  相似文献   

16.
Playing action video games enhances several different aspects of visual processing; however, the mechanisms underlying this improvement remain unclear. Here we show that playing action video games can alter fundamental characteristics of the visual system, such as the spatial resolution of visual processing across the visual field. To determine the spatial resolution of visual processing, we measured the smallest distance a distractor could be from a target without compromising target identification. This approach exploits the fact that visual processing is hindered as distractors are brought close to the target, a phenomenon known as crowding. Compared with nonplayers, action-video-game players could tolerate smaller target-distractor distances. Thus, the spatial resolution of visual processing is enhanced in this population. Critically, similar effects were observed in non-video-game players who were trained on an action video game; this result verifies a causative relationship between video-game play and augmented spatial resolution.  相似文献   

17.
18.
Three experiments investigated whether spatial information acquired from vision and language is maintained in distinct spatial representations on the basis of the input modality. Participants studied a visual and a verbal layout of objects at different times from either the same (Experiments 1 and 2) or different learning perspectives (Experiment 3) and then carried out a series of pointing judgments involving objects from the same or different layouts. Results from Experiments 1 and 2 indicated that participants pointed equally fast on within- and between-layout trials; coupled with verbal reports from participants, this result suggests that they integrated all locations in a single spatial representation during encoding. However, when learning took place from different perspectives in Experiment 3, participants were faster to respond to within- than between-layout trials and indicated that they kept separate representations during learning. Results are compared to those from similar studies that involved layouts learned from perception only.  相似文献   

19.
A sampling theoretical and experimental framework for the study of spatial vision is introduced. It is suggested that spatial Gestalt perception can be fruitfully analyzed by applying the concepts and methods of modern spatial filtering theory as they are known in the theory of image sampling and reconstruction. Demonstrations of the sampling processes in spatial vision are given and an experimental method for estimating the spatial reconstruction power of the human visual system is described. The experimental results presented suggest that high spatial frequency information has a special significance for human vision. Evidently, high frequency information is transmitted more easily through the visual system than has been generally assumed on the basis of contrast sensitivity studies.  相似文献   

20.
Unconscious stimuli can influence participants’ motor behavior but also more complex mental processes. Recent research has gradually extended the limits of effects of unconscious stimuli. One field of research where such limits have been proposed is spatial cueing, where exogenous automatic shifts of attention have been distinguished from endogenous controlled processes which govern voluntary shifts of attention. Previous evidence suggests unconscious effects on mechanisms of exogenous shifts of attention. Here, we applied a cue-priming paradigm to a spatial cueing task with arbitrary cues by centrally presenting a masked symmetrical prime before every cue stimulus. We found priming effects on response times in target discrimination tasks with the typical dynamic of cue-priming effects (Experiments 1 and 2) indicating that central symmetrical stimuli which have been associated with endogenous orienting can modulate shifts of spatial attention even when they are masked. Prime–Cue Congruency effects of perceptual dissimilar prime and cue stimuli (Experiment 3) suggest that these effects cannot be entirely reduced to perceptual repetition priming of cue processing. In addition, priming effects did not differ between participants with good and poor prime recognition performance consistent with the view that unconscious stimulus features have access to processes of endogenous shifts of attention.  相似文献   

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