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181.
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   
182.
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   
183.
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   
184.
In its early stages, Parkinson's disease (P.D.) may be difficult to distinguish from major depression (M.D.) leading to inappropriate management. Both illnesses are characterized by psychomotor retardation. The neurovegetative symptoms used to diagnose M.D. are not specific and in P.D. may be due to the physical illness itself. Currently, differentiation of the two disorders relies on subjective clinical observation. Improved diagnostic accuracy based on more objective data is needed. To this end, this study used computerized acoustic analysis to contrast speech patterns in P.D. and M.D. The sample consisted of 30 P.D. patients without depression or dementia, 30 patients with uncomplicated M.D., and 31 normal controls, each 60 years of age or over. Of the acoustic variables studied, M.D. patients had significantly reduced rates of speech compared with P.D. patients. The data suggest that this temporal measure of speech may be useful in the differentiation of P.D. and M.D.  相似文献   
185.
186.
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   
187.
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   
188.
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   
189.
Observers classified sine-wave and square-wave gratings on the basis of fundamental frequency (Are the bars wide or narrow?) or on the basis of higher harmonic frequencies (Are the bars sharp or fuzzy?). Stimuli were presented in either the left (LVF) or right (RVF) visual field. When the classification was made on the basis of the fundamental frequencies (1 or 3 c/deg), there was a LVF/right hemisphere advantage. However, when the classification was on the basis of a sharp/fuzzy distinction which involved searching for the higher harmonic frequencies, then a RVF/left hemisphere advantage was found.  相似文献   
190.
Gender differences in children's play activities, preferred school subjects, and occupational goals were examined in relation to such parental variables as toy-giving and chore assignment. Subjects were 245 children in grades K, 3, 6, and 8. Subjects completed questionnaires before and after Christmas asking what gifts they wanted, asked for, received, and liked best. They also were asked to name their friends and play activities, favorite and least-liked school subjects, occupational aspirations, and chores at home. Children generally wanted, asked for, received, and most-liked gender-typical toys. They were less likely to receive requested gender-atypical toys. Children's preferred activities, job aspirations and assigned chores were along gender-typical lines. Girls preferred masculine toys and jobs more than boys preferred feminine ones. With increasing age, both girls and boys increasingly preferred masculine toys and male friends. No gender differences in favorite or least-liked school subjects were found. School subject preference was related to gender-typing of occupational choice for girls but not boys.An earlier version of this paper was presented at the annual meeting of the American Psychological Association, Anaheim, California, 1983.  相似文献   
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