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91.
Responses to unimodal and multimodal attributes of a compound auditory/visual stimulus were investigated in 4-, 6-, 8-, and 10-month-old infants. First, infants were habituated to a compound stimulus consisting of a visual stimulus that moved up and down on a video monitor and a sound that occurred each time the visual stimulus reversed direction at the bottom. Once each infant met a habituation criterion, a series of test trials was administered to assess responsiveness to the components of the compound stimulus. Response was defined as the total duration of visual fixation in each trial. In the two unimodal test trials, the rate at which the component was presented was changed while the rate of the other component remained the same, whereas in the bimodal test trial the rate of both components was changed simultaneously. Results indicated that infants at each age successfully discriminated the bimodal and the two unimodal changes and that regression to the mean did not account for the results. Results also showed that disruption of the temporal relationship that accompanied the change in rate in the two unimodal test trials was also discriminable, but rate changes appeared to play a greater role in responsiveness than did synchrony changes. Considered together with results from similar prior studies, the current results are consistent with the modality appropriateness hypothesis in showing that discrimination of temporal changes in the auditory and visual modalities is dependent on the specialization of the sensory modalities.  相似文献   
92.
A variant of Ponzo's pattern was devised by drawing converging oblique lines at the ends of each of two horizontal lines that were located directly one above the other. Pairs of converging or diverging fins (either between or outside the horizontal shafts) were systematically removed. The results showed that, as predicted by integrative field theory, oblique lines between the shafts produced more distortion than did oblique lines outside the shafts. Also, it was shown that the attentive field construct in integrative field theory was crucial for predicting patterns of means and variances in this experiment. The modified Ponzo effect was shown to have much in common with the classical Müller-Lyer illusion. The subtle differences between the two were explained by proposing that the size of the optimum attentive field was larger in the Ponzo tasks than in the Müller-Lyer tasks because expansion fins are found on both shafts in the Ponzo-like figure.  相似文献   
93.
Thresholds for auditory motion detectability were measured in a darkened anechoic chamber while subjects were adapted to horizontally moving sound sources of various velocities. All stimuli were 500-Hz lowpass noises presented at a level of 55 dBA. The threshold measure employed was the minimum audible movement angle (MAMA)--that is, the minimum angle a horizontally moving sound must traverse to be just discriminable from a stationary sound. In an adaptive, two-interval forced-choice procedure, trials occurred every 2-5 sec (Experiment 1) or every 10-12 sec (Experiment 2). Intertrial time was "filled" with exposure to the adaptor--a stimulus that repeatedly traversed the subject's front hemifield at ear level (distance: 1.7 m) at a constant velocity (-150 degrees/sec to +150 degrees/sec) during a run. Average MAMAs in the control condition, in which the adaptor was stationary (0 degrees/sec,) were 2.4 degrees (Experiment 1) and 3.0 degrees (Experiment 2). Three out of 4 subjects in each experiment showed significantly elevated MAMAs (by up to 60%), with some adaptors relative to the control condition. However, there were large intersubject differences in the shape of the MAMA versus adaptor velocity functions. This loss of sensitivity to motion that most subjects show after exposure to moving signals is probably one component underlying the auditory motion aftereffect (Grantham, 1989), in which judgments of the direction of moving sounds are biased in the direction opposite to that of a previously presented adaptor.  相似文献   
94.
Pairs of vibrotactile patterns were presented to subjects' left middle and index fingerpads (unilateral presentation) or left and right index fingerpads (bilateral presentation), using two Optacon arrays. A set of simple (one-line) patterns and a set of complex (two-line) patterns were constructed so that they were equally identifiable when presented individually. In Experiment 1, discrimination performance was lower for two-line patterns than it was for one-line patterns, and it was lower for unilateral presentation than it was for bilateral presentation. Communality, the number of lines that two patterns share in common, was a major factor in reducing discrimination performance for two-line patterns. Subjects' abilities to identify one member of the pair of patterns were measured in Experiment 2. There were no significant differences in performance between pattern sets or type of presentation when subjects attended to a single pattern. However, when subjects were required to attend to both patterns, identification performance was lower for two-line patterns than it was for one-line patterns, and it was lower for unilateral presentation than it was for bilateral presentation. The results suggest that there are limited attentional resources for processing vibrotactile patterns and that more resources are available bilaterally than are available unilaterally.  相似文献   
95.
The concept of sin seems to have virtually disappeared from the pastoral counseling literature, and this likely reflects the possibility that it has virtually disappeared from the practice of pastoral counseling. This article presents a case for returning the concept of sin to pastoral counseling and does so by discussing the psychospiritual importance of addressing sin, defining sin in a pastorally useful way, discussing four capital sins in light of a contemporary understanding of sin, and drawing some pastoral implications.  相似文献   
96.
A previous report on the effect of the day of the full moon on the acting-out behavior of 20 developmentally delayed, institutionalized women showed that on the day of the full moon there were significantly more misbehaviors than on any other day during the lunar period. The records were re-evaluated to assess the frequency of acting-out behaviors on weekends and holidays as contrasted with the balance of the month. This re-evaluation indicated there was no significant difference between the weekends and holidays and the balance of the month (t = 1.14). The results were taken as support of the previous findings that on the day of the full moon there were significantly more misbehaviors than on any other day of the lunar period.  相似文献   
97.
The research was intended to identify the dimensions underlying self-perceived information needs and concerns of an elderly population. The spontaneously mentioned needs and concerns expressed in 271 letters from a sample of the population were extracted and a multidimensional scaling procedure was used to represent the 58 most frequently mentioned items in configurations of varying dimensionality. To interpret the multidimensional spaces, another sample of 176 elderly subjects was asked to rate the 58 concerns on eight properties. These ratings were then regressed onto the multidimensional configurations. The results indicate that the most frequently mentioned information needs and concerns of elderly persons can be parsimoniously understood in terms of three underlying dimensions: (1) Improving the Quality of Life vs Securing the Necessities of Life, (2) Health-related vs Not Health-related, and (3) Individual vs Societal Responsibility.  相似文献   
98.
The extraction of three-dimensional shape from shading is one of the most perceptually compelling, yet poorly understood, aspects of visual perception. In this paper, we report several new experiments on the manner in which the perception of shape from shading interacts with other visual processes such as perceptual grouping, preattentive search ("pop-out"), and motion perception. Our specific findings are as follows: (1) The extraction of shape from shading information incorporates at least two "assumptions" or constraints--first, that there is a single light source illuminating the whole scene, and second, that the light is shining from "above" in relation to retinal coordinates. (2) Tokens defined by shading can serve as a basis for perceptual grouping and segregation. (3) Reaction time for detecting a single convex shape does not increase with the number of items in the display. This "pop-out" effect must be based on shading rather than on differences in luminance polarity, since neither left-right differences nor step changes in luminance resulted in pop-out. (4) When the subjects were experienced, there were no search asymmetries for convex as opposed to concave tokens, but when the subjects were naive, cavities were much easier to detect than convex shapes. (5) The extraction of shape from shading can also provide an input to motion perception. And finally, (6) the assumption of "overhead illumination" that leads to perceptual grouping depends primarily on retinal rather than on "phenomenal" or gravitational coordinates. Taken collectively, these findings imply that the extraction of shape from shading is an "early" visual process that occurs prior to perceptual grouping, motion perception, and vestibular (as well as "cognitive") correction for head tilt. Hence, there may be neural elements very early in visual processing that are specialized for the extraction of shape from shading.  相似文献   
99.
Binary programming models are presented to generate parallel tests from an itembank. The parallel tests are created to match item for item an existing seed test and match user supplied taxonomic specifications. The taxonomic specifications may be either obtained from the seed test or from some other user requirement. An algorithm is presented along with computational results to indicate the overall efficiency of the process. Empirical findings based on an itembank for the Arithmetic Reasoning section of the Armed Services Vocational Aptitude Battery are given.The Office of Naval Research, Program in Cognitive Science, N00014-87-C-0696 partially supported the work of Douglas H. Jones. The Rutgers Research Resource Committee of the Graduate School of Management partially supported the work of Douglas H. Jones and Ing-Long Wu. A Thomas and Betts research fellowship partially supported the work of Ing-Long Wu. The Human Resources Laboratory, United States Air Force, partially supported the work of Ronald Armstrong. The authors benefited from conversations with Dr. Wayne Shore, Operational Technologies, San Antonio, Texas. The order of authors' names is alphabetical and denotes equal authorship.  相似文献   
100.
In keeping with Lakoff's (1975) notion that the use of women's language (WL) conveys uncertainty on the part of the speaker, the influence of communication apprehension, familiarity of partner, and topic on the use of selected WL forms was investigated. In dyadic conversation with a female friend or stranger, 71 female university students, who had completed the Personal Report of Communication Apprehension—Long, discussed a familiar or an unfamiliar topic. Multiple-regression analyses revealed that (1) communication apprehension was positively related to the use of question intonation, (2) familiarity of topic and partner were negatively related to the use of hedges, and (3) familiarity of topic was positively related to the use of intensifiers. There were no intercorrelations of the linguistic forms. These results challenge the notion that WL forms actually cohere to form a kind of language and suggest that the influence of social and psychological variables on the use of WL is much more complex and multifaceted than Lakoff believed.This article is based on portions of an Honour's thesis completed by the second author, and was presented at the Annual Convention of the Canadian Psychological Association held in Ottawa, Ontario, June 1990.  相似文献   
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