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81.
82.
Although many nonlinear models of cognition have been proposed in the past 50 years, there has been little consideration of
corresponding statistical techniques for their analysis. In analyses with nonlinear models, unmodeled variability from the
selection of items or participants may lead to asymptotically biased estimation. This asymptotic bias, in turn, renders inference
problematic. We show, for example, that a signal detection analysis of recognition memory data leads to asymptotic underestimation
of sensitivity. To eliminate asymptotic bias, we advocate hierarchical models in which participant variability, item variability,
and measurement error are modeled simultaneously. By accounting for multiple sources of variability, hierarchical models yield
consistent and accurate estimates of participant and item effects in recognition memory. This article is written in tutorial
format; we provide an introduction to Bayesian statistics, hierarchical modeling, and Markov chain Monte Carlo computational
techniques. 相似文献
83.
Fos protein expression in olfactory-related brain areas after learning and after reactivation of a slowly acquired olfactory discrimination task in the rat 下载免费PDF全文
Roullet F Liénard F Datiche F Cattarelli M 《Learning & memory (Cold Spring Harbor, N.Y.)》2005,12(3):307-317
Fos protein immunodetection was used to investigate the neuronal activation elicited in some olfactory-related areas after either learning of an olfactory discrimination task or its reactivation 10 d later. Trained rats (T) progressively acquired the association between one odor of a pair and water-reward in a four-arm maze. Two groups of pseudotrained rats were used: PO rats were not water restricted and were submitted to the olfactory stimuli in the maze without any reinforcement, whereas PW rats were water-deprived and systematically received water in the maze without any odorous stimulation. When the discrimination task was well mastered, a significantly lower Fos immunoreactivity was observed in T rats compared to PW and PO rats in most of the analyzed brain areas, which could reflect the post-acquisition consolidation process. Following memory reactivation, differences in Fos immunoreactivity between trained and some pseudotrained rats were found in the anterior part of piriform cortex, CA3, and orbitofrontal cortex. We also observed that Fos labeling was significantly higher in trained rats after memory reactivation than after acquisition of the olfactory task in most of the brain areas examined. Our results support the assumption of a differential involvement of neuronal networks after either learning or reactivation of an olfactory discrimination task. 相似文献
84.
The development of the 42-item Asian American Values Scale-Multidimensional (AAVS-M) is presented. In Study 1, data from 163 Asian American respondents were subjected to a principal components analysis, which reduced the initial set of 180 items to 42 items divided into 5 components: collectivism, conformity to norms, emotional self-control, family recognition through achievement, and humility. The data also revealed initial evidence of the AAVS-M total and subscale scores' reliability and validity. In Study 2, data from 189 Asian American respondents were subjected to a confirmatory factor analysis, which supported a hierarchical factor structure underlying the AAVS-M. Additional reliability and validity evidence of AAVS-M total and subscale scores were found. In Study 3, data from 38 Asian American respondents yielded evidence of AAVS-M total and subscale scores' test-retest reliability. 相似文献
85.
In order to investigate the body image self-perception and the prevalence of body dissatisfaction among Chinese children and adolescents, 9100 children aged 3-15 years living in four cities completed a questionnaire assessing body image self-percepts and ideals by figural stimuli. The results indicate that (1) children's body ratings started to be significantly related to their BMIs at age 5 and correlations increased with age; (2) a wide range of current body sizes was chosen by Chinese boys and girls; (3) the ideal body sizes of boys and girls selected by boys and girls, respectively, were "boys by boys">"boys by girls">"girls by boys">"girls by girls" and (4) the satisfaction, mild dissatisfaction, and moderate dissatisfaction rates were 40.1%, 36.4% and 23.5%, respectively. Differences as a function of gender and age were identified. It was concluded that the prevalence of body dissatisfaction among children and adolescents of urban China was striking, and that the Chinese boys were not immune to body dissatisfaction. 相似文献
86.
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
87.
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
88.
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
89.
Li J 《The American psychologist》2003,58(2):146-7; discussion 148-9
90.
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