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911.
This study evaluated women's understanding of prenatal ultrasound in terms of meeting the requirements for informed choice. A cross-sectional survey was conducted to evaluate (1) how information is provided, (2) women's perceived value of the information received and, (3) their understanding of ultrasound in relation to the principles of informed choice. Women (n = 113) completed a questionnaire prior to their 18-week ultrasound. Fifty-five percent stated they received no information from their care provider. Only 31.9% considered health care providers as a very helpful source of information. Yet, 69.0% stated their care provider gave them information that facilitated their understanding. Gaps were identified in women's understanding of ultrasound. Specifically, 46.0% did not view ultrasound as a screen for anomalies; some were uncertain about the safety (18.6%), diagnostic capabilities (26.5%), and limitations of testing (37.2%). These results suggest that women's understanding of ultrasound does not meet the requirements of informed choice. 相似文献
912.
Mendola P Selevan SG Gutter S Rice D 《Mental retardation and developmental disabilities research reviews》2002,8(3):188-197
A number of environmental agents have been shown to demonstrate neurotoxic effects either in human or laboratory animal studies. Critical windows of vulnerability to the effects of these agents occur both pre- and postnatally. The nervous system is relatively unique in that different parts are responsible for different functional domains, and these develop at different times (e.g., motor control, sensory, intelligence and attention). In addition, the many cell types in the brain have different windows of vulnerability with varying sensitivities to environmental agents. This review focuses on two environmental agents, lead and methylmercury, to illustrate the neurobehavioral and cognitive effects that can result from early life exposures. Special attention is paid to distinguishing between the effects detected following episodes of poisoning and those detected following lower dose exposures. Perinatal and childhood exposure to high doses of lead results in encephalopathy and convulsions. Lower-dose lead exposures have been associated with impairment in intellectual function and attention. At high levels of prenatal exposure, methylmercury produces mental retardation, cerebral palsy and visual and auditory deficits in children of exposed mothers. At lower levels of methylmercury exposure, the effects in children have been more subtle. Other environmental neurotoxicants that have been shown to produce developmental neurotoxicity include polychlorinated biphenyls (PCBs), dioxins, pesticides, ionizing radiation, environmental tobacco smoke, and maternal use of alcohol, tobacco, marijuana and cocaine. Exposure to environmental agents with neurotoxic effects can result in a spectrum of adverse outcomes from severe mental retardation and disability to more subtle changes in function depending on the timing and dose of the chemical agent. 相似文献
913.
Bonanno GA Wortman CB Lehman DR Tweed RG Haring M Sonnega J Carr D Nesse RM 《Journal of personality and social psychology》2002,83(5):1150-1164
The vast majority of bereavement research is conducted after a loss has occurred. Thus, knowledge of the divergent trajectories of grieving or their antecedent predictors is lacking. This study gathered prospective data on 205 individuals several years prior to the death of their spouse and at 6- and 18-months postloss. Five core bereavement patterns were identified: common grief, chronic grief, chronic depression, improvement during bereavement, and resilience. Common grief was relatively infrequent, and the resilient pattern most frequent. The authors tested key hypotheses in the literature pertaining to chronic grief and resilience by identifying the preloss predictors of each pattern. Chronic grief was associated with preloss dependency and resilience with preloss acceptance of death and belief in a just world. 相似文献
914.
We explored the prospect of using the bioelectrical potentiaLs of Philodendron cordatum as a new method for studying the behavior of plants. The bioelectrical potentials were recorded from equipment typically associated with EEG recordings. Plants were exposed to a 6-hr. training period of light only, dark only, or alternating 1-min. periods of light/dark. Following training, all plants were exposed to a 10-min. testing period in darkness during which bioelectrical potentials were recorded. Power of the bioelectric potentials was compared between groups of plants for frequencies between 0.1 and 10.0 Hz. Significant main effects of group and frequency were found, raising questions about the possibility of "learning" in P. cordatum. 相似文献
915.
Beauchaine TP Strassberg Z Kees MR Drabick DA 《Journal of abnormal child psychology》2002,30(1):89-101
Cognitive response repertoires to videotaped child noncompliance episodes were examined in mothers of aggressive (MAs) and nonaggressive 4–6-year-old boys. Mothers provided open-ended solutions to three subtypes of child noncompliance under conditions of time pressure, or after they waited for 15 s to consider alternatives. Solutions were coded as assistance/facilitation, coercion, deference, or explanation/clarification. Compared with controls, MAs offered fewer explanation/clarification responses, more coercive responses, and fewer unique solutions during pressured responding. Two to 6 weeks later, mothers were videotaped while participating with their sons in a challenging block-building task. Maternal responses to the vignettes predicted conflict escalation during block building, even after rates of concurrent and past child noncompliance were partialled out. Implications for parent-training models are considered. 相似文献
916.
Does prospective remembering rely on strategic, attentionally demanding processes? We report three experiments suggesting that the extent to which attentional processes are required varies according to the character of ongoing task processing. Study-test changes in the semantic context of targets had a negative effect on prospective memory performance when participants were engaged in a conceptually focused (sentence verification) task (Experiment 1). Similarly, prospective remembering was lower following study-test changes in perceptual format (font) in the context of a perceptually focused (readability rating) ongoing task (Experiment 2). However, although dividing attention at retrieval had a negative effect during the performance of an ongoing conceptual task (Experiments 1 and 3), it had no effect during an ongoing perceptual task (Experiments 2 and 3). Thus, both perceptual and conceptual process are implicated in prospective remembering, but the processing focus of the task in which remembering should occur may mediate the requirement for strategic processes. These findings suggest that more than one retrieval route is available for prospective remembering and that selection of the route depends on the nature of the task and the processing that occurs at encoding and retrieval. 相似文献
917.
In 2 experiments, participants named pictures while ignoring auditory word distractors. For pictures with homophone names (e.g., ball), distractors semantically related to the nondepicted meaning (e.g., prom) facilitated naming by top-down phonological connections for young but not for older adults. Slowing from unrelated distractors and facilitation from phonologically related distractors were age invariant except in distractors that were both semantically and phonologically related. Only distractors semantically related to the picture interfered more for older than younger adults. These results ar einconsistent with age-linked deficits in inhibition of irrelevant information from either internal or external sources. Rather, aging affects priming transmission in a connectionist network with asymmetric effects on semantic and phonological connections involved in comprehension and production, respectively. 相似文献
918.
MR imaging of fetal central nervous system abnormalities 总被引:4,自引:0,他引:4
Levine D 《Brain and cognition》2002,50(3):39-448
Ultrasound is the screening modality of choice for fetal imaging. However, when additional information regarding fetal anatomy or pathology is needed, fast MR imaging is increasingly being used as a correlative imaging modality. Performances of high quality sonographic and MR examinations as well as interpretation by individuals familiar with prenatal diagnosis are important factors for optimal parental counseling. MR imaging frequently adds additional information regarding fetal central nervous system anomalies beyond that available with ultrasound. This information commonly changes patient counseling, and at times patient management. 相似文献
919.
Predicting handwriting performance of early elementary students with the developmental test of visual-motor integration 总被引:3,自引:0,他引:3
The purpose of this study was to examine use of the Developmental Test of Visual-Motor Integration in predicting handwriting performance of early elementary students and the contribution of sex. An additional purpose was to examine whether successful completion of the first nine figures or the oblique cross from the test predicted handwriting. 101 children were tested at the beginning of their kindergarten year and again in the middle of the first-grade year on the Scale of Children's Readiness In PrinTing (SCRIPT). The VMI kindergarten scores did not significantly predict first-grade SCRIPT scores for the sample as a whole. When boys and girls were considered separately. VMI scores predicted handwriting SCRIPT scores for girls, but accounted for only 10% of the variance. Successful performance on the first nine VMI figures was significantly associated with handwriting for girls but not boys, while the oblique cross did not significantly predict handwriting performance. These results do not provide clear support for administration of the Developmental Test of Visual-Motor Integration during kindergarten as a tool to identify children at risk for handwriting difficulties. 相似文献
920.
Fisher CB Hoagwood K Boyce C Duster T Frank DA Grisso T Levine RJ Macklin R Spencer MB Takanishi R Trimble JE Zayas LH 《The American psychologist》2002,57(12):1024-1040
In response to U.S. Public Health Service projects promoting attention to disparities in the outcomes of mental health treatments, in July 2001, the American Psychological Association, the National Institute of Mental Health, and the Fordham University Center for Ethics Education convened a group of national leaders in bioethics, multicultural research, and ethnic minority mental health to produce a living document to guide ethical decision making for mental health research involving ethnic minority children and youths. This report summarizes the key recommendations distilled from these discussions. 相似文献