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141.
Much of cognitive aging research concerns whether age-associated differences in various cognitive performances can be accounted for by general explanatory constructs or whether several specific processes are involved. Structural equation models have been proposed to disentangle general and specific age-associated differences in cognitive performance. This article demonstrates that existing methods that employ stepwise procedures run the risk of biasing results toward general resource accounts. An alternative model representation (i.e., the nested factor model) is proposed that affords simultaneous estimation of general and specific effects and is applied to data from the Berlin Aging Study. Using the nested factor model allowed the authors to detect that specific group factors explained 25% of the age-associated variance in addition to the general factor. 相似文献
142.
The authors explored the temporal mechanism of attention deficit in children with attention-deficit/hyperactivity disorder (ADHD). In rapid serial visual presentation tasks in which two targets (T-sub-1 and T-sub-2) were presented in close temporal proximity among distractors, participants tried to identify T-sub-1 and detect T-sub-2 in one (dual-task) experiment and only to detect T-sub-2 in a second control (single-task) experiment. The sensitivity of T-sub-2 detection was analyzed using signal detection theory. The attentional blink--the impairment in T-sub-2 detection following the identification of T-sub-1--was increased in magnitude and protracted in the patients. Moreover, some ADHD children appeared to have a blink largely normal in magnitude but temporally displaced toward a later time. The authors hypothesize that a slower closing of the attention gate may mediate this specific attention impairment in ADHD children. 相似文献
143.
The purpose of this study was to explore adolescents' perceptions and attitudes regarding the Internet, by gender. Data were collected from 636 high school students in Taiwan. It was found that male adolescents perceived the Internet more as a "toy," while female adolescents perceived the Internet more as a "technology," "tool" or "tour." Results indicated that females held more pragmatic views of the Internet, whereas males believed they could obtain more enjoyment from the Internet. In addition, males expressed significantly more positive attitudes than did females on two aspects of the Internet: usefulness and perceived control. However, no significant gender differences were found in terms of the affection and behavior aspects of using the Internet. More importantly, females tended to show higher Internet self-efficacy than did males. It is suggested that gender differences regarding the Internet might be narrowing because female adolescents are acquiring more experience with it. 相似文献
144.
A problem with interpretations of differences in mathematic achievement between students from Asian countries and those from the United States is the seemingly implicit assumption of the cultural homogeneity of Asian societies. Researchers rarely measure the effects of variables within cultures that are hypothesized to be related to differences across cultures. In the present study, the authors examined the effects of socioeconomic status (SES) and quality of instruction on Chinese students' (1st, 3rd, and 5th grades) understanding of distance, time, and speed. The results indicated that (a) low SES in China can impede the development of children's mathematical cognition and (b) higher SES does not guarantee better performance. The implication is that the gap in mathematical performance between socioeconomically advantaged and disadvantaged children can be narrowed or even eliminated through instructional practices that focus on the systematic training of children's mathematical thinking. 相似文献
145.
Selective age-related differences in source memory relative to item memory, and individual differences in memory performance in relation to anxiety were explored with high- and low-anxious subjects screened from normal young and elderly adults. They were read false facts about the locations of well-known and unknown sights in a male or female voice. Intentional and incidental learning instructions were administered for source memory. Selective age-related deficits in source memory were observed under both encoding conditions. Higher level of anxiety was related to lower memory performance only in the old group; this relation was stronger in source recall. The findings suggest that the presence of such selectivity is unrelated to the tradeoff between item encoding and source encoding. Anxiety affects the variability, and mediates the selectivity of age effects on episodic memory. 相似文献
146.
Li J 《The American psychologist》2003,58(2):146-7; discussion 148-9
147.
Limits on theory of mind use in adults 总被引:10,自引:0,他引:10
148.
Temporal integration of speech prosody is shaped by language experience: an fMRI study 总被引:5,自引:0,他引:5
Gandour J Dzemidzic M Wong D Lowe M Tong Y Hsieh L Satthamnuwong N Lurito J 《Brain and language》2003,84(3):318-336
Differences in hemispheric functions underlying speech perception may be related to the size of temporal integration windows over which prosodic features (e.g., pitch) span in the speech signal. Chinese tone and intonation, both signaled by variations in pitch contours, span over shorter (local) and longer (global) temporal domains, respectively. This cross-linguistic (Chinese and English) study uses functional magnetic resonance imaging to show that pitch contours associated with tones are processed in the left hemisphere by Chinese listeners only, whereas pitch contours associated with intonation are processed predominantly in the right hemisphere. These findings argue against the view that all aspects of speech prosody are lateralized to the right hemisphere, and promote the idea that varying-sized temporal integration windows reflect a neurobiological adaptation to meet the 'prosodic needs' of a particular language. 相似文献
149.
This study tested Annett's right-shift theory on spatial ability with two samples from China. The Vandenberg Mental Rotation Test (MRT), Edinburgh Handedness Inventory, and Family Handedness Questionnaire were administered to 266 high school students and 297 undergraduates. We found very few r++ or r-- among Chinese students. Most Chinese are either moderately right-handed or ambidextrous. Consistent with Casey's finding, we found using different methods to classify handedness leads to different conclusions. However, we did not find the effect of familial handedness that Casey found. Visual strategy is related to success on the MRT but handedness is not. 相似文献
150.
S Li 《Perceptual and motor skills》2001,93(1):124-126
Cultural and ethnic influence on proxemic behavior and invasions of personal space were investigated. 173 Chinese Singaporean undergraduates rated minimum interpersonal distance for perceived male intruders from four ethnic groups in Singapore--Malay, Indian, Chinese, and Caucasian. Rated distance scores ranked from "most distant" Indian Chinese dyads decreasing (in order of minimum distance) through Malay-Chinese. Caucasian-Chinese, and Chinese-Chinese dyads, independent of sex. 相似文献