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161.
The classical visual latency explanation of the Pulfrich phenomenon is generalized to allow for the possibility that the visual system uses velocity information from motion detectors to compensate for spatial lag due to time lag, in identifying the instantaneous position of a moving object. The results of the reported experiment verify one consequence of the generalized version: the elliptical apparent path is skewed away from the filtered eye. The results suggest also that the extrapolation factor increases with visual latency and that there is a different extrapolation factor for each eye when the eyes are illuminated unequally. 相似文献
162.
R A Jones G D Morrow B R Morris J B Ries D R Wekstein 《Perceptual and motor skills》1992,74(1):227-238
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
163.
R B?sel 《Zeitschrift für experimentelle und angewandte Psychologie》1992,39(3):372-395
Based on previous findings (B?sel et al., 1990) it was assumed that in concept learning tasks generating on hypotheses on a concept which has to be developed is accompanied by increases of the Alpha 1 power (7.5-10 Hz) in the spontaneous EEG activity. In this study 16 subjects performed five problem solving tasks with similar processing requirements. EEG data were analyzed by means of post hoc comparisons of subjects differing in performance quality. Additionally, four control tasks were employed in which, based on previous studies, variations in the Theta frequency range were expected. An effect in the Alpha 1 frequency band was observed in tasks requiring reconstructive recall or testing the usefulness of an mathematical algorithm. The creation of a rank order or mental map is accompanied by power increases in the lower portions of the Alpha 1 frequency band (7.5-8.5 Hz). Moreover a high amount of controlled variance (eta2 up to 34%) was obtained for this effect. Increases in EEG Theta power, which presumably indicate subjects' component analysis, were found before the subjects recognized parts of geometric figures or before relevant features in the "buddhist monk problem" were discriminated. The dynamics of EEG power over time is in examples of frequency/time plots in a figure, illustrated. 相似文献
164.
B Gsellhofer P Montoya A Müller C Piesbergen R Schandry 《Zeitschrift für experimentelle und angewandte Psychologie》1992,39(3):419-433
This study explored the relationship between individual strategies of coping and blood pressure responses during and after mental stress. Blood pressure behavior was measured noninvasively and continuously before, during and after a mental stress situation in 27 normotensive subjects. Coping strategies were assessed with the Stressverarbeitungsfragebogen (SVF; coping with stress inventory). Two extreme groups were formed on the basis of the scores in the SVF. Results were: (a) Individuals who used coping strategies characterized by controlling the situation directly and constructively, in contrast to probands not using these strategies, exhibited lower blood pressure during the stress situation and a faster return to baseline levels after cessation of stress. (b) Subjects using a coping behavior characterized by the use of defense mechanisms such as suppression and denial, also showed lower blood pressure during stress but a significantly delayed return to baseline levels of blood pressure after stress was concluded. 相似文献
165.
30 subjects participated in a discrimination experiment learning face-letter associations under four rotation conditions (45 degrees, 90 degrees, 135 degrees, 180 degrees). Under each condition two thirds of the faces were presented twice, upright and rotated away from the vertical; the remaining faces were presented once, upright or rotated. Learning is described by a joint Markov model: For faces that are presented twice it assumes a separate association and encoding process (two-stage-model), for faces that are presented once it assumes an association process (all-or-none-model). The Markov model fits the data for all four rotation conditions. The angle of rotation does not affect learning for faces that are presented once. For faces that are presented twice it influences both the association and the encoding process. For the angles employed, the effect of rotation can be approximated linearly. The results suggest that the encoding of a rotated face differs increasingly from an upright face as a function of these angles of rotation. This confirms analogous conclusions from mental rotation experiments. 相似文献
166.
167.
Three experiments are reported that represent a reexamination of the missing-number method (Buschke, 1963b) of estimating short-term memory span. The missing-number task involved presenting a random sequence of all but one of the numbers of a known reference set and asking subjects to identify the missing number. Experiment 1 introduced a modified missing-number task that included two missing items and two choices made by the subject. With a large decline in performance for the second choice relative to the first, it is possible that only the second choice was subject to output or retrieval interference. An alternative explanation is that subjects output the number with the weakest memory representation as their first response. By postcuing subjects to report their two choices in a forward or backward sequence, Experiment 2 provided evidence against the importance of output interference and support either for the importance of retrieval interference or for the "weakest-first" hypothesis. However, with a paradigm that replaced only correctly identified missing numbers, a prediction that subjects would select the number with the weakest memory representation as their first response was not confirmed in Experiment 3. Instead, retrieval interference was implicated to explain the first-choice superiority found in Experiments 1 and 3. The results were interpreted in terms of the TODAM model of Murdock (1982, 1987, in press). 相似文献
168.
B P McCloskey R L Klatzky J W Pellegrino 《Journal of experimental psychology. Human perception and performance》1992,18(4):948-961
Previous research (Klatzky et al., 1989) shows that the time required to make sensible/nonsensible judgments about an action-object phrase (e.g., "rub your stomach") is reliably faster when the phrase is preceded by a cure representing a specific prototypical hand shape (vs. a neutral cue). The current experiments investigated the effects of preparing for an alternate task (finger tapping vs. syllable vocalization) on facilitatory priming of sensibility judgments. Preparation for finger tapping reduced the magnitude of the priming effect more than preparation for vocalization, suggesting that resources accessed during semantic processing of action-object phrases are also used during manual response preparation. The results support the existence of a system representing manual actions that is limited in the number of activities that can be represented at one time and that is not so general that it represents manual and vocal tract movements. 相似文献
169.
Arthur J. Reynolds Roger P. Weissberg Wesley J. Kasprow 《American journal of community psychology》1992,20(5):599-624
Investigated predictors of five measures of early school adjustment for an ethnically diverse cohort of 683 inner-city kindergartners and first graders. Data from 2 consecutive years were collected from teachers, school records, and children. A multiple-regression preduction model significantly explained children's competence behavior, problem behavior, reading achievement, mathematics achievement, and school absences. Prior adjustment and sociodemographic factors explained a majority of the variance in adjustment. Perceived quality of parent involvement was signifcantly related (in the expected direction) to all five outcomes. Exposure to life events was significantly associated in the expected direction with competence behavior, problem behavior, and school absences but not with reading and mathematics achievement. Together, parent involvement and life-event variables explained as much as 12% of the variance in adjustment independent of sociodemographic and prior adjustment factors. The role of family and school factors in the adjustment of children at risk is discussed [corrected]. 相似文献
170.
S B Chapman K A Culhane H S Levin H Harward D Mendelsohn L Ewing-Cobbs J M Fletcher D Bruce 《Brain and language》1992,43(1):42-65
This study examined narrative discourse in 20 children and adolescents at least 1 year after sustaining a head injury. Narratives were analyzed along the dimensions of language structure, information structure, and flow of information. Severity of impaired consciousness was associated with a significant reduction in the amount of language and information. The most important finding which emerged was the disruption in information structure. This pattern confirms the impression of disorganized discourse in severely injured children. Explanations for the disruption in information structure are explored in terms of the role of vocabulary, memory, and localization of lesion according to magnetic resonance imaging. In view of recent evidence that frontal lobe damage is associated with discourse formulation deficits in adults and is the most common site of focal lesion in closed head injury, we examined discourse patterns in individual patients with frontal lobe lesions. Preliminary data from our single-case studies suggest discourse patterns similar to those reported for adults with frontal lobe injuries. 相似文献