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991.
Gabriel A. Radvansky Laura A. Carlson-Radvansky David E. Irwin 《Memory & cognition》1995,23(5):596-606
Magnitude estimations involving spatial characteristics, such as distance, typically show a compressive function when estimates are made from memory. In particular, as the magnitude of a property grows larger and larger, estimates become more and more inaccurate, with increasing underestimates of the actual magnitude. Previous theories have attempted to explain this difference by supposing that magnitude estimation was accomplished through a reperceptual process, in which the errors of perception are magnified, or a transformation process, in which the memory trace undergoes a consistent alteration toward a more schematic form. The present experiments present evidence in support of an uncertainty hypothesis. When subjects are uncertain of the actual value of a distance, they are forced to guess on the basis of the mean distance they encountered, because they are unable to retrieve the information accurately. When they can retrieve the information, they are more certain and their estimates are more accurate. This hypothesis was also extended to integrative conditions in which the subjects were presented with the stimulus display in a piecemeal fashion. In these cases, distance estimates were derived by combining spatial representations. This method of presentation caused distance estimates to become less accurate. 相似文献
992.
Janice E. Murray 《Memory & cognition》1995,23(1):49-58
In two experiments, the naming of rotated line drawings of natural objects was examined after a training phase in which the objects were either attended or ignored. In the training phase of Experiment 1, subjects were presented with objects in a number of orientations over five repeated blocks of trials. In the center of each object, seven letters (Xs and Ts, colored red or blue) were presented in rapid succession. Half the subjects named aloud the rotated object and ignored the changing letter display (object-attend). The other half ignored the object and counted the number of red Ts, and then used this number to perform a simple multiplication (object-ignore). In the test phase, all subjects named the rotated objects. The results showed that in the first block of trials in the training phase, mean naming time in the object-attend condition increased the further an object was rotated from the upright. This effect of orientation for attended objects was much reduced in the later presentations of the test phase. In contrast, there was no such benefit of prior presentation observed for the naming of objects that had previously been ignored. Instead, a substantial orientation effect was shown for the naming of previously ignored objects, which was similar to the orientation effect observed for attended objects named in the first block. Similar results were found in Experiment 2, in which object-attend subjects in training covertly named the objects and then performed a letter count and multiplication task. In both experiments, performance on the letter count and multiplication task varied with the angle of the ignored object. The results suggest that full attentional resources must be allocated in order for orientation-invariant representations to be formed and used in the identification of rotated objects. 相似文献
993.
Michelle Bidaut-Russell Wendy Reich Linda B. Cottler Lee N. Robins Wilson M. Compton Richard E. Mattison 《Journal of abnormal child psychology》1995,23(5):641-659
To identify reasons for discrepancies between parent and child reports of child/adolescents's psychiatric symptoms, parents and adolescents (51 pairs) were asked to guess what the other would answer to questions from the PC-DISC about the adolescent's psychiatric symptoms, and to explain why they expected disagreement when the answer they provided for the other was different from their own. Adolescents' explanations for expecting (1) parental denial of symptoms the adolescent reported were: the parent was unaware of, forgot about, assumed the adolescent could not have, or trivialized the symptom; and (2) parental report of symptoms the adolescent denied were: the parent misread or exaggerated the adolescent's symptom, had too high expectations for the adolescent's behavior, put a negative label on or did not trust the adolescent. Parents' reasons for expecting their children to (1) deny symptoms the parents reported were: the adolescent did not remember how s/he felt, lied, did not recognize or minimized the importance or frequency of the symptom; and (2) report symptoms the parents denied were: the adolescent lied, exaggerated the importance of or interpreted the symptom differently.Support for this work was provided by National Institute of Drug Abuse grant number DA-05585 (Dr. Cottler, P.I.), and National Institute of Mental Health grants numbers MH-31302 (Dr. R. C. Cloninger, P.I.) and MH-17104 (Dr. Cottler, P.I.).Address all correspondence, including reprint requests, to Michelle Bidaut-Russell, Ph.D, MPH, MPE, Department of Psychiatry, Box 8134, Washington University School of Medicine, 4940 Children's Place, St. Louis, Missouri 63110. 相似文献
994.
Lozoff B Park AM Radan AE Wolf AW 《International journal of behavioral development》1995,18(2):277-295
It has been established through several decades of research that children's home environments significantly influence their development. Many researchers have also been interested in expanding research beyond indirect measures of the home environment, such as socioeconomic status, to help understand the nature of specific environmental mechanisms which influence early behavior and cognitive development. The Home Observation for Measurement of the Environment (HOME) Inventory was developed to meet these needs. Specifically, HOME measures the quality of stimulation in a child's early family environment. Almost all studies of the approach's reliability and validity have been conducted with US samples. HOME is, however, being used in other countries. The authors report their findings from a study of whether the psychometric properties of HOME based upon US samples parallel those found in Costa Rica, and whether HOME discriminates between Costa Rican environments with different associations to child health and development. Focus centers upon the infant/toddler version of the HOME Inventory. HOME data for 183 healthy Costa Rican infants were compared to the original HOME standardization sample from Little Rock, Arkansas. The study found the HOME Inventory to be helpful in identifying children at risk for delayed development in this Latin American sample. Lower HOME scores related to a shorter duration of breastfeeding and differentiated children with iron deficiency anemia in infancy, a condition associated with long-lasting developmental disadvantage. 相似文献
995.
Previous research indicates that low scores on the Raven's Advanced Progressive Matrices (RAPM) test are associated with increased cortical glucose utilization during problem solving. We hypothesized that previous results may reflect the neurophysiological consequences of patterns of effort requirements; that is, high-effort expenditure from lower aptitude participants (for whom the problems are hard) and low-effort expenditure from higher aptitude participants (for whom the problems are easy). In this experiment, positron emission tomography (PET) data were gathered on participants (N = 28) who solved easy and hard problems that were tailored to the participants' own ability levels, thereby eliminating aptitude group differences in effort requirements. Contrary to previous results, high aptitude was associated with high cortical glucose use. Average aptitude participants showed diminished glucose use in the hard condition. A significant Group X Condition X Hemisphere Effect was also noted, with greater right hemisphere activation in the hard condition for the high-aptitude group. These results demonstrate that the relation of cerebral glucose use and cognitive ability is sensitive to participant and task selection. 相似文献
996.
Research suggests that males outperform females on standardized tests of math ability from early adolescence onward. Several explanations for this difference focus on the different experiences of females and males with numerical information. We reasoned that males have more experience with numerical information than females because typical male interests (e.g., sports) are more likely to involve numerical information than typical female interests (e.g., physical appearance). Thus, we predicted that males would attend more to numerical information than would females, at least when the information was presented in a male-related or gender-neutral context. Females were expected to attend more than males when the context was female-related. Results using White/Caucasian subjects provided some support for these predictions. Implications for future research on the relationship between the gender-linkage of math materials and gender differences in math performance are discussed. 相似文献
997.
Mentor relationships and the career development of pregnant and parenting African-American teenagers 总被引:2,自引:0,他引:2
The influence of natural mentor relationships on the career outlook of African-American pregnant and parenting teenagers was examined. More than half of the participants nominated adults they considered to be mentors. A path model indicated that mentor support was associated with increased life optimism, beyond its indirect effects on career activities and beliefs about the opportunity structure. These findings suggest that natural mentors are an important resource in the career developmnent of pregnant and parenting African-American adolescents. 相似文献
998.
College counseling can best be understood as the intersection of a professional activity and an environment. The specialty has developed from the merging of several movements: vocational guidance, mental health, and student personnel work. These elements are reflected in the diversity of backgrounds and perspectives represented by college counselors and in differing models of counseling services. College counseling will be affected by trends including health care reform, scarcity of resources in higher education, changing student demographics, and complex societal issues. 相似文献
999.
Sarah E. Zemore 《Current Psychology》1995,14(1):83-88
To evaluate the ability to generate mental images and its relations to artistic training, 44 undergraduates were presented
with a list of selected fragments from 40 characters in the Roman alphabet. Subjects provided those letters suggested by the
fragments for as many items as possible within a 90-second interval. It was hypothesized that students who had received college
training in studio art would be able to produce a greater number of candidate images than students not trained in art, resulting
in more correct answers and higher scores. Results confirmed the hypothesis. Trained subjects completed significantly more
of the letters on the image-generation task than did those not trained in art (p=.0001). This suggests that superior ability
to generate images is associated with artistic training. Further, these results imply that, to the degree to which artistic
training reflects ability, image generation may also be related to artistic ability. 相似文献
1000.