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1.
Cognitive studies of map interpretation, for both paper‐based and digital maps (e.g. in geographic information systems), have generally assumed awareness of the map's geographic representational characteristics. However, many tasks using a digital map do not require visualization of the geographic environment it represents, but a conflicting focus on the geometric properties of the visual array. An experimental study demonstrated that the tasks performed and linguistic terms used with a digital map influenced the user's mental representation, as reflected by ease of orientation within the actual geographic environment (as measured by an unexpected photograph interpretation task). The map was still present during this task, since the concern was with interpretation rather than recall. No gender, age or expertise effects were found. Results are discussed with regard to the concept of reference frames and other spatial distinctions. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

2.
In binocular brightness perception a phenomenon called Fechner's paradox can be observed. This paradox implies non-monotonicities in the psychometric functions of binocular brightness. Lehky (1983) proposed a model that describes such non-monotonicities. He suggested that Fechner's paradox also exists in binaural loudness perception. However, until now no sufficient data have been collected to test this hypothesis. Therefore, an experiment was conducted in which 36 psychometric functions were obtained using binaural stimuli in the range of intensities in which Fechner's paradox supposedly occurs. As a result, no significant non-monotonicities were found. However, it is shown that jnds derived from the psychometric functions contradict predictions derived from the limited binaural additivity model of Gigerenzer and Strube (1983).  相似文献   

3.
Impaired tool related action in ideomotor apraxia is normally ascribed to loss of sensorimotor memories for habitual actions (engrams), but this account has not been tested against a hypothesis of a general deficit in representation of hand-object spatial relationships. Rapid reaching for familiar tools was compared with reaching for abstract objects in apraxic patients (N = 9) and in a control group with right hemisphere posterior stroke. The apraxic patients alone showed an impairment in rotating the wrist to correctly grasp an inverted tool but not when inverting the hand to avoid a barrier and grasp an abstract object, and the severity of the impairment in tool reaching correlated with pantomime of tool-use. A second experiment with two apraxic patients tested whether barrier avoidance was simply less spatially demanding than reaching for a tool. However, the patient with damage limited to the inferior parietal lobe still showed a selective problem for tools. These results demonstrate that some apraxic patients are selectively impaired in their interaction with familiar tools, and this cannot be explained by the demands of the task on postural or spatial representation. However, traditional engram theory cannot account for associated problems with imitation of novel actions nor the absence of any correlated deficit in recognition of the methods of grasp of common tools. A revised theory is presented which follows the dorsal and ventral streams model ( Milner & Goodale, 2008) and proposes preservation of motor control by the dorsal stream but impaired modulating input to it from the conceptual systems of the left temporal lobe.  相似文献   

4.
The integrity of Web-delivered experiments: can you trust the data?   总被引:3,自引:0,他引:3  
Data from Web-delivered experiments conducted in browsers by remote users of PsychExperiments, a public on-line psychology laboratory, reveal experiment effects that mirror lab-based findings, even for experiments that require nearly millisecond accuracy of displays and responses. Textbook results are obtained not just for within-subjects effects, but for between-subjects effects as well. These results suggest that existing technology is adequate to permit Web delivery of many cognitive and social psychological experiments and that the added noise created by having participants in different settings using different computers is easily compensated for by the sample sizes achievable with Web delivery.  相似文献   

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6.
De Bruyn B  Orban GA 《Perception》1999,28(6):703-709
To compare transparent motion and kinetic boundaries with unidirectional motion, in many studies the relative motion is generated by superimposing or adjoining unidirectional motions oriented in opposite directions. The presumption, tacitly underlying this comparison, is that the two oppositely directed velocities are independent of one another as far as their speed is concerned, i.e. the speed of the relative motion is presumed to be equivalent to the speed of the unidirectional components. Here we report that the relative motion between dots moving in opposite directions augments perceived speed. A constant-stimuli procedure was used to pair transparent-motion or kinetic-boundary displays with unidirectional motion, and human observers were asked to match the speed of the relative and unidirectional motions. The results show that transparency and kinetic boundaries increase the perceived visual speed by about 50%, compared with the speed of the individual components.  相似文献   

7.
The aim of this paper is to demonstrate that empirically delimited structures of mind are also differentiable by means of systematic logical analysis. For the sake of this aim, the paper first summarizes Demetriou’s theory of cognitive organization and growth. This theory assumes that the mind is a multistructural entity that develops across three fronts: the processing system that constrains processing potentials, a set of specialized structural systems (SSSs) that guide processing within different reality and knowledge domains, and a hypercognitive system that monitors and controls the functioning of all other systems. The second part of the paper focuses on the SSSs, which are the target of our logical analysis, and it summarizes a series of empirical studies demonstrating their autonomous operation. The third part develops the logical proof showing that each SSS involves a kernel element that cannot be reduced to standard logic or to any other SSS. The implications of this analysis for the general theory of knowledge and cognitive development are discussed.  相似文献   

8.
We examined how a highly familiar environmental space--one's city of residence--is represented in memory. Twenty-six participants faced a photo-realistic virtual model of their hometown and completed a task in which they pointed to familiar target locations from various orientations. Each participant's performance was most accurate when he or she was facing north, and errors increased as participants' deviation from a north-facing orientation increased. Pointing errors and latencies were not related to the distance between participants' initial locations and the target locations. Our results are inconsistent with accounts of orientation-free memory and with theories assuming that the storage of spatial knowledge depends on local reference frames. Although participants recognized familiar local views in their initial locations, their strategy for pointing relied on a single, north-oriented reference frame that was likely acquired from maps rather than experience from daily exploration. Even though participants had spent significantly more time navigating the city than looking at maps, their pointing behavior seemed to rely on a north-oriented mental map.  相似文献   

9.
Music provides a useful domain in which to study how the different attributes of complex multidimensional stimuli are processed both separately and in combination. Much research has been devoted to addressing how the dimension of pitch and time are co-processed in music listening tasks. Neuropsychological studies have provided evidence for a certain degree of independence between pitch and temporal processing, although there are also many experimental reports favouring interactive models of pitch and temporal processing. Here we extended these investigations by examining the processing of pitch and temporal structures when music is presented in the visual modality (i.e. in the form of music notation). In two experiments, musician subjects were presented with visual musical stimuli containing both pitch and temporal information for a brief amount of time, and they were subsequently required to recall both the pitch and temporal information. In Experiment 1, we documented that concurrent, unattended, pitch and rhythmic auditory interference stimuli disrupted the recall of pitch, but not time. In Experiment 2, we showed that manipulating the tonal structure of the visual presentation stimuli affected the recall of pitch, but not time. On the other hand, manipulating the metrical properties of the visual stimuli affected recall of time, and pitch to a certain extent. Taken together, these results suggest that the processing of pitch is constrained by the processing of time, but the processing of time is not affected by the processing of pitch. These results do not support either strong independence or interactive models of pitch and temporal processing, but they suggest that the processing of time can occur independently from the processing of pitch when performing a written recall task.  相似文献   

10.
The present study investigated whether infants learn the effects of other persons' actions like they do for their own actions, and whether infants transfer observed action-effect relations to their own actions. Nine-, 12-, 15- and 18-month-olds explored an object that allowed two actions, and that produced a certain salient effect after each action. In a self-exploration group, infants explored the object directly, whereas in two observation groups, infants first watched an adult model acting on the object and obtaining a certain effect with each action before exploring the objects by themselves. In one observation group, the infants' actions were followed by the same effects as the model's actions, but in the other group, the action-effect mapping for the infant was reversed to that of the model. The results showed that the observation of the model had an impact on the infants' exploration behavior from 12 months, but not earlier, and that the specific relations between observed actions and effects were acquired by 15 months. Thus, around their first birthday infants learn the effects of other persons' actions by observation, and they transfer the observed action-effect relations to their own actions in the second year of life.  相似文献   

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12.
A pure tone changing continuously in intensity shows sweep-induced fading (SIF) of loudness as intensity sweeps down and may show a lesser degree of sweep-induced enhancement (SIE) as intensity sweeps up (Canévet & Scharf, 1990); the former effect has been calleddecruitment, the latterupcruitment. An opposite effect—upsweeps being judged to show more loudness change than downsweeps—has been reported by Neuhoff (1998). These disparate results might stem from several procedural differences. We found that differences in the sweep’s duration and intensity level did not account for the disparity, nor did the presence of a steady tone preceding the sweep. In a second experiment, direct judgments of sweep size, such as those Neuhoff’s (1998) listeners made, were affected not only by sweep size itself, but also by the intensity at the end of the sweep. The latter effect was especially marked for upsweeps. Neuhoff’s (1998) proposed “bias for rising intensities” was found only with a method for judging sweep size that is more sensitive to end level than to sweep size.  相似文献   

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In this article we discuss five requirements that theoretically must be fulfilled for transnatal chemosensory learning to occur in three placental species, the rat, the sheep, and the human, viz. (1) minimum or partial maturity of nasal chemoreceptor systems, (2) efficient odorivector compounds in the fetal environment, (3) the ability to memorize chemosensory information across birth, (4) perinatal continuity in chemical signals, (5) neonatal ability to detect air-borne odorants previously experienced in the aquatic environment. A substantial body of data is reviewed for the rat, in which fetal chemosensation is now firmly established. The less studied ovine perinate also shows preliminary evidence of nasal chemoreception and of postnatal retention of prenatally experienced odorants. Concerning the human species, we discuss extensive anatomical data supporting nasochemoreception in utero, but as yet no direct or indirect functional demonstration is provided. Furthermore, the strongest evidence of odorivector compounds in amniotic fluid is from human data. The results presented allow generalization of chemosensory functioning in utero in the species considered.  相似文献   

15.
Event-related potentials (ERPs) offer unique insights into processes related to involuntary attention changes triggered by rare, unpredictably occurring sensory events, that is, distraction. Contrasting ERPs elicited by distracters and frequent standard stimuli in oddball paradigms allowed the formulation of a three-stage model describing distraction-related processing: first, the distracting event is highlighted by a sensory filter. Second, attention is oriented towards the event, and finally, the task-optimal attention set is restored, or task priorities are changed. Although this model summarizes how distracting stimulus information is processed, not much is known about the cost of taking this exceptional route of processing. The present study demonstrates the impact of distraction on sensory processing. Participants performed a Go/NoGo tone-duration discrimination task, with infrequent pitch distracters. In the two parts of the experiment the duration-response mapping was reversed. Contrasts of distracter and standard ERPs revealed higher P3a- and reorienting negativity amplitudes for short than for long tones, independently from response type. To understand the cause of these asymmetries, short vs. long ERP contrasts were calculated. The ERP pattern showed that short standards elicited an attention-dependent offset response, which was abolished for short distracters. That is, the apparent P3a- and RON enhancements were caused by the removal of a task-related attentional sensory enhancement. This shows that the disruption of task-optimal attention set precedes the elicitation of the P3a, which suggests that P3a does not reflect a process driving the initial distraction-related attention change.  相似文献   

16.
17.
In spite of recent political setbacks for the movement toward universal health insurance, considerable support remains for the idea. Among those supporting such plans, most assume that a universal insurance system, especially if it is a single-payer system, would offer a single list of basic covered services. This paper challenges that assumption and argues for the availability of multiple lists of services in a universal insurance system. The claim is made that multiple lists will be both more efficient and more fair. Any single list will fund some services that are quite attractive to some people, but only marginally attractive to others. Thus any single-list plan will fund some services that produce only marginal benefit for the resources used. Moreover, since some people will hold values quite compatible with the single list and others will hold values leading to preferences for unfunded services, some people will get much more benefit from any single list than other people will. Fairness and efficiency require providing an entitlement to universal access to health insurance that could be purchased by typical consumers for a fixed price of perhaps $3500. By permitting everyone to pick their preferred list of services available at that price, each person will efficiently use his or her entitlement while getting more equal opportunity for benefits.  相似文献   

18.
Two experiments tested humans on a memory for duration task based on the method of Wearden and Ferrara (1993) Wearden, J. H. and Ferrara, A. 1993. Subjective shortening in humans' memory for stimulus duration. Quarterly Journal of Experimental Psychology, 46B: 163186.  [Google Scholar], which had previously provided evidence for subjective shortening in memory for stimulus duration. Auditory stimuli were tones (filled) or click-defined intervals (unfilled). Filled visual stimuli were either squares or lines, with the unfilled interval being the time between two line presentations. In Experiment 1, good evidence for subjective shortening was found when filled and unfilled visual stimuli, or filled auditory stimuli, were used, but evidence for subjective shortening with unfilled auditory stimuli was more ambiguous. Experiment 2 used a simplified variant of the Wearden and Ferrara task, and evidence for subjective shortening was obtained from all four stimulus types.  相似文献   

19.
Two experiments tested humans on a memory for duration task based on the method of Wearden and Ferrara (1993), which had previously provided evidence for subjective shortening in memory for stimulus duration. Auditory stimuli were tones (filled) or click-defined intervals (unfilled). Filled visual stimuli were either squares or lines, with the unfilled interval being the time between two line presentations. In Experiment 1, good evidence for subjective shortening was found when filled and unfilled visual stimuli, or filled auditory stimuli, were used, but evidence for subjective shortening with unfilled auditory stimuli was more ambiguous. Experiment 2 used a simplified variant of the Wearden and Ferrara task, and evidence for subjective shortening was obtained from all four stimulus types.  相似文献   

20.
Juvenile homicide remains a serious problem in the U.S., despite recent decreases in the juvenile arresr rate for murder. Reflecting on her clinical experiences evaluating 90 adolescent murderers, the author identifies 15 factors that appear to have contributed to the escalation in juvenile homicide beginning in the mid-198os. These factors can be grouped into five categories: situational factors (child abuse and neglect, and the absence of positive male role models), societal influences (the crisis in leadership and lack of heroes, and witnessing violence), resource availability (access to guns, involvement in alcohol and drugs, and poverty and lack of resources), personality characteristics (low self-esteem, the inability to deal with strong feelings, boredom, poor judgement, and prejuduce and hatred), and their cumulative effects (little or nothing to lose and the biological connection). Strategies to reduce juvenile violence are addressing using parents, schools, communities, government leaders, the media and individuals. ©1997 John Wiley & Sons, Ltd.  相似文献   

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