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1.
The effects of subunit formation on adult listeners' ability to notice changes in a continuous spectral gradient of sound were studied. Results of this experiment support the idea that the auditory system processes information differently within a unit, and that this processing does not occur unless the perceptual system detects unit boundaries. In this experiment, silences were inserted into a continuously changing sound to cause the formation of short units. Listeners noticed the change earlier in conditions with silences inserted than in to conditions where the transition was either unbroken or broken by loud noise bursts. Results are discussed in terms of two processes, one that accentuates stimulus properties present at moments of onset and offset, and a second that uses onsets and offsets to signal the beginnings and ends of units and reduces the change perceived within units.  相似文献   

2.
Cognitive models of reading all assume some division of labor among processing pathways in mapping among print, sound and meaning. Many studies of the neural basis of reading have used task manipulations such as rhyme or synonym judgment to tap these processes independently. Here we take advantage of specific properties of the Chinese writing system to test how differential availability of sublexical information about sound and meaning, as well as the orthographic structure of characters, pseudo-characters and “artificial” control stimuli influence brain activation in the context of the same one-back task. Analyses combine a data-driven approach that identifies temporally coherent patterns of activity over the course of the entire experiment with hypothesis-testing based on the correlation of these patterns with predictors for different stimulus classes. The results reveal a large network of task-related activity. Both the extent of this network and activity in regions commonly observed in studies of Chinese reading are apparently related to task difficulty. Other regions, including temporo-parietal cortex, were sensitive to particular sublexical functional units in mapping among print, sound, and meaning.  相似文献   

3.
Organic and behavioral evolution both involve variation, selection, and replication with retention; but the individuals involved in these processes differ in the two kinds of evolution. In this paper, biological units of evolution, selection, and retention are compared with analogous units at the behavioral level. In organic evolution, natural selection operates on variations among organisms within a species, with the result of preserving in future generations of organisms those heritable characteristics that contributed to the organism's survival and reproduction. Species evolve as characteristics of the population change as a result of past selection. Continuity in a lineage in the biosphere is maintained by replication of genes with retention of organismic characteristics across successive generations of organisms. In behavioral evolution, reinforcement operates on variations among responses within an operant, with the result of preserving in future responses those characteristics that resulted in reinforcement. Continuity in a behavioral lineage, within the repertoire of a given organism, appears to involve retention and replication, but the unit of retention and replication is unknown. We suggest that the locus of retention and replication is the nervous system of the behaving organism.  相似文献   

4.
We report an experiment designed to investigate 6-to-7-year-old children's ability to acquire knowledge of sublexical correspondences between print and sound from their reading experience. A computer database containing the printed word vocabulary of children taking part in the experiment was compiled and used to devise stimuli controlled for grapheme-phoneme correspondence (GPC) frequency and rime neighbourhood consistency according to the children's reading experience. Knowledge of GPC rules and rime units was compared by asking children to read aloud three types of nonword varying in regularity of GPC and consistency of rime pronunciation. Results supported the view that children can acquire knowledge of both GPC rules and rime units from their reading experience. GPC rule strength affects the likelihood of a GPC response; rime consistency affects the likelihood of a rime response.  相似文献   

5.
The psychodynamic literature has associated clients' silences in psychotherapy sessions with a variety of processes. These processes include wishes to merge with the therapist, to gain control in session, to communicate the unsayable, to express helplessness and, most frequently, the intertwined processes of resistance and regression. Experiences of obstructive silence—that is, moments in which clients detached from the process of therapeutic inquiry—were examined in this study. A grounded theory analysis was used to explore clients' experiences of silences in psychotherapy across psychotherapeutic modalities. Two types of obstructive pausing processes, Disengaged pauses and Interactional pauses, were identified. The implications of delineating conscious aspects of these complex experiences are stressed and techniques are suggested for therapeutic intervention in moments of experienced threat.  相似文献   

6.
A technique for implementing real-time experiments utilizing several separate and independent programs is discussed. The technique can be employed when the experimental procedure is divided into real-time and nonreal-time program units. These program units are executed in the most appropriate computing environment, and the resulting output is directed to a sequential file. The nonreal-time program issues commands to the real-time program by means of keywords that are inserted in the sequential file output at those points where real-time operations are required. These commands are interpreted by the real-time program which processes the sequential file. While the nonreal-time program is experiment-specific, the real-time program is independent of the particular experiment performed. The applications of this multiprogram approach to real-time experimentation are considered.  相似文献   

7.
Rethinking perceptual organization: The role of uniform connectedness   总被引:1,自引:0,他引:1  
A principle of perceptual organization, calleduniform connectedness (UC), is described, and a theoretical approach to perceptual organization is proposed in which this principle plays a fundamental role. The principle of UC states that closed regions of homogeneous properties—such as lightness, chromatic color, texture, and so forth—tend to be perceived initially as single units. We demonstrate its effects and show that they occur even when opposed by powerful grouping principles such as proximity and similarity. We argue that UC cannot be reduced to such grouping principles, because it is not a form of grouping at all. We then propose a theoretical framework within which UC accounts for the initial (orentry level) organization of the visual field into primitive units. Classical principles of grouping operate after UC, creating superordinate units consisting of two or more basic-level units. Parsing processes also operate after UC, dividing basic-level units into subordinate parts. UC in the retinal image is proposed to be a necessary, but not a sufficient, condition for unit formation, since connected elements on the retina that are perceived to lie in separate depth planes fail to be perceived as units. This fact, together with other evidence that the Gestalt principles of grouping are based onperceived (rather than retinal) relations, suggests that the organization of visual stimulation into UC objects is ultimately achieved within a relatively late, postconstancy representation of environmental surfaces. The implications of this possibility are discussed in light of present theories of visual perception.  相似文献   

8.
9.
Humans have remarkable statistical learning abilities for verbal speech-like materials and for nonverbal music-like materials. Statistical learning has been shown with artificial languages (AL) that consist of the concatenation of nonsense word-like units into a continuous stream. These ALs contain no cues to unit boundaries other than the transitional probabilities between events, which are high within a unit and low between units. Most AL studies have used units of regular lengths. In the present study, the ALs were based on the same statistical structures but differed in unit length regularity (i.e., whether they were made out of units of regular vs. irregular lengths) and in materials (i.e., syllables vs. musical timbres), to allow us to investigate the influence of unit length regularity on domain-general statistical learning. In addition to better performance for verbal than for nonverbal materials, the findings revealed an effect of unit length regularity, with better performance for languages with regular- (vs. irregular-) length units. This unit length regularity effect suggests the influence of dynamic attentional processes (as proposed by the dynamic attending theory; Large & Jones (Psychological Review 106: 119–159, 1999)) on domain-general statistical learning.  相似文献   

10.
According to feature integration theory, conjunction search is conducted via a serial self-terminating search. However, effects attributed to search processes operating on the entire display may actually reflect search restricted to elements defined by a single feature. In experiment 1 this question is addressed in a reaction-time (RT) paradigm by varying distractor ratios within an array of fixed size. For trials in which the target was present in the array, RT functions were roughly symmetric, the shortest RTs being for extreme distractor ratios, and the longest RTs being for arrays in which there were an equal number of each distractor type. This result is superficially consistent with Zohary and Hochstein's interpretation that subjects search for only one distractor type and are able to switch search strategy from trial to trial. However, negative-trial data from experiment 1 case doubt on this interpretation. In experiment 2 the possible role of 'pop out' and of distractor grouping in visual conjunction search is investigated. Results of experiment 2 suggest that grouping may play a more important role than does distractor ratio, and point to the importance of the spatial layout of the target and of the distractor elements in visual conjunction search. Results of experiment 2 also provide clear evidence that groups of spatially adjacent homogeneous elements may be processed as a unit.  相似文献   

11.
Structuring of early reaching movements: a longitudinal study   总被引:1,自引:0,他引:1  
Reaches, performed by 5 infants, recorded at 19 weeks of age and every third week thereafter until 31 weeks of age, were studied quantitatively. Earlier findings about action units were confirmed. At all ages studied, movements were structured into phases of acceleration and deceleration. Reaching trajectories were found to be relatively straight within these units and to change direction between them. It was also found that at all ages, there was generally one dominating transport unit in each reach. The structuring of reaching movements changed in four important ways during the period studied. First, the sequential structuring became more systematic with age, with the dominating transport unit beginning the movement. Second, the duration of the transport unit became longer and covered a larger proportion of the approach. Third, the number of action units decreased with age, approaching the two-phase structure of adult reaching. Finally, reaching trajectories became straighter with age.  相似文献   

12.
Reaches, performed by 5 infants, recorded at 19 weeks of age and every third week thereafter until 31 weeks of age, were studied quantitatively. Earlier findings about action units were confirmed. At all ages studied, movements were structured into phases of acceleration and deceleration. Reaching trajectories were found to be relatively straight within these units and to change direction between them. It was also found that at all ages, there was generally one dominating transport unit in each reach. The structuring of reaching movements changed in four important ways during the period studied. First, the sequential structuring became more systematic with age, with the dominating transport unit beginning the movement. Second, the duration of the transport unit became longer and covered a larger proportion of the approach. Third, the number of action units decreased with age, approaching the two-phase structure of adult reaching. Finally, reaching trajectories became straighter with age.  相似文献   

13.
The mechanisms of perceptual learning are analyzed theoretically, probed in an orientation-discrimination experiment involving a novel nonstationary context manipulation, and instantiated in a detailed computational model. Two hypotheses are examined: modification of early cortical representations versus task-specific selective reweighting. Representation modification seems neither functionally necessary nor implied by the available psychophysical and physiological evidence. Computer simulations and mathematical analyses demonstrate the functional and empirical adequacy of selective reweighting as a perceptual learning mechanism. The stimulus images are processed by standard orientation- and frequency-tuned representational units, divisively normalized. Learning occurs only in the "read-out" connections to a decision unit; the stimulus representations never change. An incremental Hebbian rule tracks the task-dependent predictive value of each unit, thereby improving the signal-to-noise ratio of their weighted combination. Each abrupt change in the environmental statistics induces a switch cost in the learning curves as the system temporarily works with suboptimal weights.  相似文献   

14.
采用单探测变化检测范式,通过两个实验探讨了三维双特征图形在视空间工作记忆中的存储方式。实验一的记忆材料为由颜色和形状两种基本特征组成的三维图形,实验二的材料为由基本特征和细节特征组成的三维图形。被试为60名大学本科生(实验1、2各30名,年龄在19~24岁之间,平均21.25岁和21.71岁)。两个实验的结果均显示:特征交换变化条件下的记忆成绩与单一特征变化条件下最小的平均检测正确率无显著差异。这表明,由两种异质特征组成的三维图形在视觉客体和视觉空间工作记忆中均能以整合的单元进行存储。  相似文献   

15.
Prolonged listening to unidirectional change of sound level in a tone can cause a steady tone afterwards to change in apparent loudness in the opposite direction. Subjectively the present aftereffect appears strong immediately after removal of the adaptor, becoming much weaker within a second or so. To confirm this, the aftereffect was measured by nulling with different durations of test stimulus changing steadily in sound level. As predicted, rate of change of sound level was greater for the shorter test stimuli. This suggests that aftereffect measurement by nulling may be best achieved with short test stimuli. However, responses to shorter test stimuli were generally more scattered.  相似文献   

16.
Five experiments are described. Experiments 1 to 3 used a case-change methodology to test the hypothesis that orthographic onsets serve as units of visual word recognition. It was assumed that presenting words in mixed case would disrupt processing more strongly when the case change occurred within a subunit of word recognition than when the case change occurred between subunits of word recognition. The orthographic onset hypothesis was supported in two of three experiments. The sensitivity of the case-change methodology as a means of testing the orthographic onset hypothesis was examined in two further experiments using case change to disrupt orthographic rimes. Again, mixed results were observed. Given the abundance of evidence that, for skilled readers, ortho-graphic rimes serve as functional units of print and independent arguments that the case-change methodology represents an inherently conservative test of hypotheses concerning multiletter units of print, the current results provide preliminary evidence for the ortho-graphic onset as a functional unit of print.This research was funded by the Australian Research Council. I would like to thank Julie Hansen, Mataji Kennedy, and Anne O'Brien for their assistance with testing. The writing of this paper was completed at Haskins Laboratories, New Haven, Connecticut.  相似文献   

17.
In the introduction to this special issue of Organizational Behavior and Human Decision Processes on the psychological foundations of knowledge transfer in organizations, we argue that knowledge transfer is becoming increasingly important in organizations. Organizations that are able to transfer knowledge effectively from one unit to another are more productive and more likely to survive than those that are less adept at knowledge transfer. Although organizations are able to realize remarkable increases in performance through knowledge transfer, successful knowledge transfer is difficult to achieve. The articles in this special issue identify factors affecting knowledge transfer in organizations. These articles provide empirical evidence about effective mechanisms for transferring knowledge as well as about barriers to and facilitators of knowledge transfer. By focusing on the psychological processes that underlie knowledge transfer within a unit and between units within a firm, this special issue complements work in cognitive psychology on knowledge transfer at the individual level of analysis as well as work in strategy and organizational theory on knowledge transfer at the firm or industry levels of analysis. This special issue opens up the “black box” of knowledge transfer in organizations by providing new theory and empirical evidence on the psychological processes that are the foundations for knowledge transfer in organizations.  相似文献   

18.
Audiovisual phenomenal causality   总被引:1,自引:0,他引:1  
We report three experiments in which visual or audiovisual displays depicted a surface (target) set into motion shortly after one or more events occurred. A visual motion was used as an initial event, followed directly either by the target motion or by one of three marker events: a collision sound, a blink of the target stimulus, or the blink together with the sound. The delay between the initial event and the onset of the target motion was varied systematically. The subjects had to rate the degree of perceived causality between these events. The results of the first experiment showed a systematic decline of causality judgments with an increasing time delay. Causality judgments increased when additional auditory or visual information marked the onset of the target motion. Visual blinks of the target and auditory clacks produced similar causality judgments. The second experiment tested several models of audiovisual causal processing by varying the position of the sound within the visual delay period. No systematic effect of the sound position occurred. The third experiment showed a subjective shortening of delays filled by a clack sound, as compared with unfilled delays. However, this shortening cannot fully explain the increased tolerance for delays containing the clack sound. Taken together, the results are consistent with the interpretation that the main source of the causality judgments in our experiments is the impression of a plausible unitary event and that perfect synchrony is not necessary in this case.  相似文献   

19.
Involvement has long been theoretically specified as a crucial factor determining the persuasive impact of messages. In social judgment theory, ego‐involvement makes people more resistant to persuasion, whereas in dual‐process models, high‐involvement people are susceptible to persuasion when argument quality is high. It is argued that these disparate predictions might be reconciled by either different involvement types (i.e., value relevant vs. outcome relevant) or different attitude modification processes (i.e., attitude change vs. attitude formation). An experiment (N = 684) varying topic, position advocated, outcome relevance, and argument quality tested these moderators. The data were consistent with existence of two different types of involvement, but none of the theoretical predictions were consistent with the data. Instead, a main effect for argument quality had the largest impact on attitude change. Regardless of value‐relevant involvement, outcome‐relevant involvement, and attitude modification process, participants were more persuaded by high‐ rather than low‐quality arguments, with boomerang effects observed for low‐quality arguments. These findings highlight the importance of sound message design in persuasion.  相似文献   

20.
Insofar as counting is directed toward a definite quantification goal, only items that qualify as valid instances of what is being quantified should be included in the count. Thus, the choice of what to treat as a unit to be counted depends upon one's quantification goals. The present research examined developmental changes in the way children define units for counting. In the first experiment, children were shown arrays of toy animals and asked to count either the number of families or the number of individuals within a family. In the second and third experiments, the stimuli were objects that came apart into two pieces. Children were shown arrays composed of some intact objects and some objects that were separated into their parts, and they were asked either to count the number of wholes or the number of pieces in the entire array. Virtually all the counts children generated were based on some type of common unit, even if it was only defined by physical discreteness. However, marked age differences emerged in children's adaptation of their counting units to what they were asked to count.  相似文献   

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