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841.
Using a Visual Recognition Memory (VRM) procedure, we examined the effect of encoding time on retention by 1- and 4-year olds. Irrespective of age, shorter familiarization time reduced retention, and longer familiarization time prolonged retention. The amount of familiarization that yielded retention after a given delay decreased as a function of age. 相似文献
842.
Rudd MD Berman AL Joiner TE Nock MK Silverman MM Mandrusiak M Van Orden K Witte T 《Suicide & life-threatening behavior》2006,36(3):255-262
The current article addresses the issue of warning signs for suicide, attempting to differentiate the construct from risk factors. In accordance with the characteristic features discussed, a consensus set of warning signs identified by the American Association of Suicidology working group are presented, along with a discussion of relevant clinical and research applications. 相似文献
843.
Gould MS Greenberg T Munfakh JL Kleinman M Lubell K 《Suicide & life-threatening behavior》2006,36(6):601-613
The purpose of this study was to examine the attitudes toward the use of telephone crisis services (hotlines) among 519 adolescents in 9th through 12th grade mandatory health courses in six high schools in New York State. Few adolescents (2.1%) used hotlines and negative attitudes were stronger toward hotlines than they were toward other formal sources of help. The most common reasons for hotline nonuse related to feelings of self-reliance and shame. Objections to hotlines were strongest among students most in need of help by virtue of impaired functioning or feelings of hopelessness. The results underscore needed outreach efforts to youth. 相似文献
844.
As engineers gain experience and become experts in their domain, the structure and content of their knowledge changes. Two studies are presented that examine differences in knowledge representation among freshman and senior engineering students. The first study examines recall of mechanical devices and chunking of components, and the second examines whether seniors represent devices in a more abstract functional manner than do freshmen. The most prominent differences between these 2 groups involve their representation of the functioning of groups of electromechanical components and how these groups of components interact to produce device behavior. Seniors are better able to construct coherent representations of devices by focusing on the function of sets of components in the device. The findings from these studies highlight some ways in which the structure and content of mental representations of design knowledge differ during the early stages of expertise acquisition. 相似文献
845.
846.
The prepared mind: neural activity prior to problem presentation predicts subsequent solution by sudden insight 总被引:3,自引:0,他引:3
Kounios J Frymiare JL Bowden EM Fleck JI Subramaniam K Parrish TB Jung-Beeman M 《Psychological science》2006,17(10):882-890
Insight occurs when problem solutions arise suddenly and seem obviously correct, and is associated with an "Aha!" experience. Prior theorizing concerning preparation that facilitates insight focused on solvers' problem-specific knowledge. We hypothesized that a distinct type of mental preparation, manifested in a distinct brain state, would facilitate insight problem solving independently of problem-specific knowledge. Consistent with this hypothesis, neural activity during a preparatory interval before subjects saw verbal problems predicted which problems they would subsequently solve with, versus without, self-reported insight. Specifically, electroencephalographic topography and frequency (Experiment 1) and functional magnetic resonance imaging signal (Experiment 2) both suggest that mental preparation leading to insight involves heightened activity in medial frontal areas associated with cognitive control and in temporal areas associated with semantic processing. The results for electroencephalographic topography suggest that noninsight preparation, in contrast, involves increased occipital activity consistent with an increase in externally directed visual attention. Thus, general preparatory mechanisms modulate problem-solving strategy. 相似文献
847.
Young children experience considerable difficulty in learning their first few color terms. One explanation for this difficulty is that initially they lack a conceptual representation of color sufficiently abstract to support word meaning. This hypothesis, that prior to learning color terms children do not represent color as an abstraction, was tested in two experiments using samples of 25- to 39-month-olds and 20- to 32-month-olds. Children's ability to conceptually represent color and their knowledge of color terms were assessed, and a strong association was found between the ability to make inferences based on color and the comprehension of color words. Children who did not comprehend color terms were unsuccessful at a conceptual task that required them to represent color as a property independent of the particular objects that displayed it. The results suggest that the initial absence of an abstract representation of color contributes to the difficulty that young children encounter when first learning color words. 相似文献
848.
The frontal hypothesis of cognitive aging: factor structure and age effects on four frontal tests among healthy individuals 总被引:1,自引:0,他引:1
With 101 healthy aging adult participants, the authors investigated whether executive functions are a unitary concept. The authors established the factor structure of the Wisconsin Card Sorting Test (WCST; E. A. Berg, 1948), the Stroop color and word test (C. J. Golden, 1978), verbal fluency using the Controlled Oral Word Association Test (COWAT; Benton, 1967), and the Digits Backwards subtest of the Wechsler Adult Intelligence Scale-Revised (WAIS-R; D. Wechsler, 1981). The authors also evaluated the extent to which age and other demographic variables predicted common underlying properties of these frontal tests. Results revealed an age-related decline in executive abilities differentially reflected by the selected tasks. These data suggest caution using the COWAT to evaluate executive abilities in older people. The authors interpret findings to support the unitary view of executive abilities and the executive decline proposed by the frontal hypothesis. 相似文献
849.
Heinonen K Räikkönen K Matthews KA Scheier MF Raitakari OT Pulkki L Keltikangas-Järvinen L 《Journal of personality》2006,74(4):1111-1126
We examined whether dispositional optimism and pessimism (overall LOT-R and optimism and pessimism component scores) of 694 adults aged 24 and 27 were associated with socioeconomic status (SES) measured concurrently and in childhood at ages 3 and 6. SES measures included education, occupational status and unemployment, and income. Concurrent adulthood SES was associated with the overall LOT-R and optimism and the pessimism component scores. Childhood family SES predicted overall LOT-R and pessimism component scores, even after controlling statistically for the adulthood SES. Social mobility between SES of family of origin and current SES also influenced the scores. The current findings suggest that the foundation of dispositional optimism and pessimism is related to early SES of the family. 相似文献
850.