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221.
Fos protein expression in olfactory-related brain areas after learning and after reactivation of a slowly acquired olfactory discrimination task in the rat
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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
222.
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
223.
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
224.
Darlene L. Witte‐Townsend Emily DiGiulio 《International Journal of Children's Spirituality》2004,9(2):127-142
Witte‐Townsend and DiGiulio explore some of the dimensions of knowing that children, teachers and parents may engage together during story‐time. They reflect on some of their own long‐term relationships with children and children's books, especially Phoebe Gilman's Something from nothing (published in 1992) and Simms Taback's Joseph had a little overcoat, published in 1999. The authors probe issues such as why children ask to hear a favourite story over and over and why they suddenly abandon all interest and move on to a new book. They explore the meaning of the silences that sometimes arise during story‐time, pooling around the young listeners as the last words of the book are read. Witte‐Townsend and DiGiulio remind us of the value of literature in the lives of children and they affirm that the reading and re‐reading of favourite stories enables the understanding of complex human issues and contributes significantly to social, emotional and spiritual growth. 相似文献
225.
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
226.
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
227.
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
228.
By regarding the latent random vectors as hypothetical missing data and based on the conditional expectation of the complete-data
log-likelihood function in the EM algorithm, we investigate assessment of local influence of various perturbation schemes
in a nonlinear structural equation model. The basic building blocks of local influence analysis are computed via observations
of the latent variables generated by the Metropolis-Hastings algorithm, while the diagnostic measures are obtained via the
conformal normal curvature. Seven perturbation schemes, including some perturbation schemes on latent vectors, are investigated.
The proposed procedure is illustrated by a simulation study and a real example.
Acknowledgment: This research is fully supported by a grant (CUHK 4243/02H) from the Research Grant Council of the Hong Kong
Special Administration Region. The authors are indebted to ICPSR and the relevant funding agency for allowing use of their
data, and to the Editor and reviewers for their valuable comments for improving the paper. 相似文献
229.
When determining how much to rely on olfactory information, accurate estimates of olfactory ability are important. Nevertheless, metacognitive errors regarding olfactory ability are common in the normal population. Are older adults less accurate at estimating olfactory ability, or do they simply tend to make a particular type of estimation error? We examined data from 203 patients, all of whom self-rated olfactory ability and then were tested with the Odorant Confusion Matrix. The patients' self-reports did not match the objective measure of olfactory ability in 42% of the cases, thus demonstrating a high level of impairment in metacognitive knowledge. Neither the cause of loss nor the patient's age was related to the inability to accurately estimate olfactory loss, but both contributed to the type of metacognitive errors patients made. Younger patients tended to underestimate their olfactory ability, thus behaving similarly to patients with "blindsight" who demonstrate residual visual function in the absence of awareness. Older patients tended to overestimate their olfactory ability, thus making the metacognitive error of deficit unawareness that is observed in a number of other clinical syndromes. These findings indicate that older patients are not necessarily more likely to make errors in estimating their olfactory ability; rather, they are more prone to a particular type of metacognitive error than are younger patients. 相似文献
230.
Li J 《The American psychologist》2003,58(2):146-7; discussion 148-9