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201.
Effects of experience on fetal voice recognition   总被引:1,自引:0,他引:1  
Abstract - The ability of human fetuses to recognize their own mother's voice was examined. Sixty term fetuses were assigned to one of two conditions during which they were exposed to a tape recording of their mother or a female stranger reading a passage. Voice stimuli were delivered through a loudspeaker held approximately 10 cm above the maternal abdomen and played at an average of 95 dB SPL. Each condition consisted of three 2-min periods: no stimulus, voice (mother or stranger), and no stimulus. Fetal heart rate increased in response to the mother's voice and decreased in response to the stranger's; both responses were sustained for 4 min. The finding of differential behavior in response to a familiar versus a novel voice provides evidence that experience influences fetal voice processing. It supports an epigenetic model of speech perception, presuming an interaction between genetic expression of neural development and species-specific experience.  相似文献   
202.
The authors examined the level and structure of the Inventory of Interpersonal Problems-Circumplex version (IIP-C; L. M. Horowitz, L. E. Alden, J. S. Wiggins, & A. L. Pincus, 2000) before and after 20 sessions of acute-phase cognitive therapy for depression (N = 118), as well as associations with the Schedule for Nonadaptive and Adaptive Personality (L. A. Clark, 1993b) and the Social Adjustment Scale--Self-Report version (M. M. Weissman & S. Bothwell, 1976). Interpersonal problems had a 3-factor structure (Interpersonal Distress, Love, and Dominance), with the latter 2 factors approximating a circumplex, both before and after therapy. Interpersonal Distress decreased and social adjustment increased with therapy, but the Love and Dominance dimensions were relatively stable, similar to personality constructs. Social adjustment related negatively to Interpersonal Distress but not to Love or Dominance. Personality pathology related broadly to Interpersonal Distress and discriminantly to Love and Dominance. These findings support the reliability and validity of the IIP-C and are discussed in the context of personality theory and measurement.  相似文献   
203.
We previously reported that a total methanolic extract of the underground part of Angelica gigas Nakai (Umbelliferae) (here-in-after abbreviated AG) significantly inhibited acetylcholinesterase (AChE) activity. We characterized 12 coumarin derivatives including both decursin and decursinol from extracts of AG. In this study, we evaluated the anti-amnestic activity of decursin, a major coumarin constituent isolated from AG, in vivo using ICR mice with amnesia induced by scopolamine (1 mg/kg body weight, s.c.). Decursin, when administered to mice at 1 and 5 mg/kg body weight i.p., significantly ameliorated scopolamine-induced amnesia as measured in both the passive avoidance test and the Morris water maze test. Moreover, decursin significantly inhibited AChE activity by 34% in the hippocampus of treated mice. These results indicate that decursin may exert anti-amnestic activity in vivo through inhibition of AChE activity in the hippocampus.  相似文献   
204.
205.
A 15-year-old girl's daily life is a vivid testimony to the hardships the Korean high school student is faced with. She leaves home for school at 7 A. M., taking two lunch bags, one for supper, with her. After regular classes end at 5 P.M., she attends the "autonomous study classes" studying by herself until 10 P.M. The exhausted young girl returns home at about 10:30 P.M. and gets to bed around midnight at the earliest. Under the current system, this will be her life for three years. Of course, there is no guarantee she will be able to enter the university she wants. She has no family life, except for Sundays, and they hardly ever see each other, let alone get together at the dining table for dinner. People call this "ipsi chiok," entrance examination hell. ["High School Students Deprived of Spring," 1996, p. 13].  相似文献   
206.
A novel, neuropsychologically informed paradigm (extended retrieval of events in response to a cue word) was used to investigate the neural basis of autobiographical and semantic memory. Contrasting retrieval of autobiographical memories with retrieval of semantic facts (ABM-SEM) in 24 subjects across three PET studies revealed bilateral involvement of the middle temporal gyrus (BA 21) and medial frontal cortex (BA 9/10). The opposite contrast, SEM-ABM, resulted in increased regional cerebral blood flow in left posterior temporal regions (BA 37) and left prefrontal cortex (BA 45/46). Laterality maps suggest that the bilateral pattern seen in our studies, but not often in other neuroimaging investigations, reflects the use of a task stressing retrieval of specific personal events. Further comparisons revealed that the activation in the right anterior temporal lobe during autobiographical recall was virtually identical to that seen during retrieval of information about famous people or events in contrast with retrieval of general semantic facts. These findings suggest that the retrieval of an autobiographical event requires participation from conceptual knowledge, and that this type of knowledge is bilaterally distributed in the temporal lobes.  相似文献   
207.
Lukatela G  Eaton T  Lee C  Turvey MT 《Cognition》2001,78(3):B41-B52
The phonological codes activated in visual word recognition can be thought of minimally as strings of discrete and unstructured phoneme-like units. We asked whether these codes might additionally express a letter string's phonological form at a featural or gestural level. Specifically, we asked whether the priming of a word (e.g. sea, film, basic) by a rhyming non-word would depend on the non-word's phonemic-feature similarity to the word. The question was asked within a mask--prime--target--mask sequence with both brief (57 ms in Experiments 1 and 2) and long (486 ms in Experiment 1) prime durations. Non-word primes that differed from their targets by a single phonemic feature (initial voicing as in ZEA, VILM, PASIC) led to faster target lexical decisions than non-word primes that differed by more than a single phonemic feature (e.g. VEA, JILM, SASIC). Visual word recognition seems to involve a sub-phonemic level of processing.  相似文献   
208.
Little research has been carried out on human performance in optimization problems, such as the Traveling Salesman problem (TSP). Studies by Polivanova (1974, Voprosy Psikhologii, 4, 41–51) and by MacGregor and Ormerod (1996, Perception & Psychophysics, 58, 527–539) suggest that: (1) the complexity of solutions to visually presented TSPs depends on the number of points on the convex hull; and (2) the perception of optimal structure is an innate tendency of the visual system, not subject to individual differences. Results are reported from two experiments. In the first, measures of the total length and completion speed of pathways, and a measure of path uncertainty were compared with optimal solutions produced by an elastic net algorithm and by several heuristic methods. Performance was also compared under instructions to draw the shortest or the most attractive pathway. In the second, various measures of performance were compared with scores on Raven's advanced progressive matrices (APM). The number of points on the convex hull did not determine the relative optimality of solutions, although both this factor and the total number of points influenced solution speed and path uncertainty. Subjects' solutions showed appreciable individual differences, which had a strong correlation with APM scores. The relation between perceptual organization and the process of solving visually presented TSPs is briefly discussed, as is the potential of optimization for providing a conceptual framework for the study of intelligence. Received: 28 December 1998 / Accepted: 20 January 2000  相似文献   
209.
Theoretical Medicine and Bioethics -  相似文献   
210.
In modern digital applications, users often interact with virtual representations of themselves or others, called avatars. We examined how these avatars and their perspectives influence stimulus–response compatibility in a Simon task. Participants responded to light/dark blue stimuli with left/right key presses in the presence of a task-irrelevant avatar. Changes in stimulus–response compatibility were used to quantify changes in the mental representation of the task and perspective taking toward this avatar. Experiments 1 and 2 showed that perspective taking for an avatar occurred in orthogonal stimulus–response mappings, causing a compatibility effect from the avatar’s point of view. In the following two experiments we introduced a larger variety of angular disparities between the participant and avatar. In Experiment 3, the Simon effect with lateralized stimulus positions remained largely unaffected by the avatar, pointing toward an absence of perspective taking. In Experiment 4, after avatar hand movements were added in order to strengthen the participants’ sense of agency over the avatar, a spatial compatibility effect from the avatar’s perspective was observed again, and hints of the selective use of perspective taking on a trial-by-trial basis were found. Overall, the results indicate that users can incorporate the perspective of an avatar into their mental representation of a situation, even when this perspective is unnecessary to complete a task, but that certain contextual requirements have to be met.  相似文献   
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