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11.
Implicit memory is independent from IQ and age but not from etiology: evidence from Down and Williams syndromes 总被引:1,自引:0,他引:1
S. Vicari L. Verucci & G. A. Carlesimo 《Journal of intellectual disability research : JIDR》2007,51(12):932-941
Background In the last few years, experimental data have been reported on differences in implicit memory processes of genetically distinct groups of individuals with Intellectual Disability (ID). These evidences are relevant for the more general debate on supposed asynchrony of cognitive maturation in children with abnormal brain development. This study, comparing implicit memory processes in individuals with Williams syndrome (WS) and Down syndrome (DS), was planned to verify the ‘etiological specificity’ hypotheses pertaining to the skill learning abilities of individuals with ID. Method A modified version of Nissen and Bullemer's (1987) Serial Reaction Time (SRT) task was used. The performances of three group were evaluated. The first group consisted of thirty‐two people with WS (18 males and 14 females). The second group was comprised of twenty‐six individuals with DS (14 males and 12 females). The two groups of individuals with ID were selected so that the groups were comparable as for mental age and chronological age. The third group consisted of forty‐nine typically developed children with a mental age similar to that of the groups with WS and DS. Results The two groups of individuals with ID demonstrated different patterns of procedural learning. WS individuals revealed poor implicit learning of the temporal sequence of events characterizing the ordered blocks in the SRT task. Indeed, differently from normal controls, WS participants showed no reaction time (RT) speeding through ordered blocks. Most importantly, the rebound effect, which so dramatically affected normal children's RTs passing from the last ordered to the last block, had only a marginal influence on WS children's RTs. Differently from the WS group, the rate of procedural learning of the participants with DS was comparable to that of their controls. Indeed, DS and typically developed individuals showed parallel RT variations in the series of ordered blocks and, more importantly, passing from the last ordered to the last block. Therefore, a substantial preservation of skill learning abilities in this genetic syndrome is confirmed. Conclusions The results of the present study document that procedural learning in individuals with ID depends on the aetiology of the syndrome, thus supporting the etiological specificity account of their cognitive development. These results are relevant for our knowledge about the qualitative aspects and the underlying neurobiological substrate of the anomalous cognitive development in mentally retarded people. 相似文献
12.
A. J. Esbensen M. M. Seltzer & J. S. Greenberg 《Journal of intellectual disability research : JIDR》2007,51(12):1039-1050
Background Little is known about the mortality of individuals with Down syndrome who have lived at home with their families throughout their lives. The current study evaluates the predictors, causes and patterns of mortality among co‐residing individuals in midlife with Down syndrome as compared with co‐residing individuals with ID owing to other causes. Method This paper examines mortality in 169 individuals with and 292 individuals without Down syndrome from 1988 to 2007. Dates and causes of death were obtained from maternal report, the Social Security Death Index and the National Death Index. Risk factors predicting mortality, including demographic variables, transition variables, and initial and change measures of health, functional abilities and behaviour problems, were obtained from maternal report. Results Having Down syndrome is a risk factor of mortality, net of other risk factors including older age, poorer functional abilities, worsening behaviour problems, residential relocation and parental death. The causes of death among individuals with and without Down syndrome who are in midlife and co‐residing with their families are similar, and are most commonly due to cardiovascular or respiratory problems. Conclusions The findings indicate that midlife adults with Down syndrome who co‐reside with their families generally exhibit similar causes of mortality as do midlife adults with intellectual disability owing to other causes, but show an elevated risk of mortality in midlife net of other variables, such as age and changes in functional abilities and behaviour problems. 相似文献
13.
Jasen M. Walker 《Journal of occupational rehabilitation》1992,2(4):201-209
An appropriate paradigm for explaining the evident problems of motivating the workers' compensation claimant toward occupational recovery may be found in the learned helplessness model. This article examines the critical relationships in the workers' compensation system and the potential for development of the injured worker helplessness within that system. The author offers the learned helplessness model as an alternative framework through which injured worker behavior can be explained and understood. It is suggested that the non-contingent rewards and the uncontrollable dynamics characteristic of workers' compensation systems lead to claimants' learning helplessness. Finally, a total quality managed disability prevention system is offered as the organization's best approach to reducing the likelihood of learned helplessness. 相似文献
14.
15.
S. G. Sullivan R. Hussain E. J. Glasson & A. H. Bittles 《Journal of intellectual disability research : JIDR》2007,51(3):228-231
Background Down syndrome is one of the commonest causes of intellectual disability. As life expectancy improves with early and more intensive surgical and medical treatments, people with the disorder are more likely to exhibit classic morbidity and mortality patterns and be diagnosed with diseases such as cancer. Methods A profile of cancer cases among people with Down syndrome has been compiled, based on the analysis of a linked data set that included information from the Disability Services Commission of Western Australian and the State Cancer Registry. Results and conclusions Although the total age‐ and sex‐standardized incidence ratios (SIRs) for people with Down syndrome were similar to that for the general population, SIRs for leukaemia were significantly higher while the incidence of certain other types of cancers was reduced. Overall, there was a lower incidence of solid tumours in Down syndrome, possibly reflecting the age profile of the study cohort. 相似文献
16.
Industrial back belts and low back pain: Mechanisms and outcomes 总被引:1,自引:0,他引:1
The recent increased utilization of industrial back belts as personal protective equipment in the workplace has generated considerable controversy among occupational health and safety professionals in the United States. The purpose of this article is to review the literature regarding proposed mechanisms of action of these devices and studies related to outcome of belt utilization in the prevention of low back pain and disability in the workplace. At the present time, neither the suspected mechanisms of action nor the efficacy of these devices in the primary, secondary, and tertiary prevention of work-related low back pain has been adequately demonstrated in clinical trials. As a result, generally accepted guidelines regarding the safe use of belts in the occupational setting have not been established. Based on this review it is recommended that further well-controlled, prospective, randomized clinical trials are necessary to evaluate the effectiveness of these devices as personal protective equipment. During the interim, the decision to prescribe belts to employees in the workplace should be at the discretion of an adequately trained occupational health care provider. These devices should not be provided as an alternative to appropriate administrative and/or engineering controls. 相似文献
17.
18.
49, XXXXY karyotype syndrome has been thought of as a variant of Klinefelter's syndrome. It has an incidence of between 1/85 000 to 1/100 000 live births. Typical clinical features include coarse faces, skeletal abnormalities, hypogenitalism and severe learning difficulties. Common ocular features include hypertelorism, epicanthic folds and up-slanting palpebral apertures. Here we report a case of high myopia and its successful correction leading to a positive personality change in one such patient. We advocate full ophthalmic examination, under anaesthesia if necessary, and a trial of refractive correction, even in children thought unlikely to tolerate such. 相似文献
19.
J De Reuck I Claeys S Martens Ph Vanwalleghem G Van Maele R Phlypo H Hallez 《European journal of neurology》2006,13(4):402-407
It is not well established whether seizures and epilepsy after an ischaemic stroke increase the disability of patients. Seventy-two patients with delayed seizures after a hemispheric infarct (37 with a single seizure and 35 with epilepsy) were included in the study. The modified Rankin scale was used to compare disability of the patients at 1 month after stroke and at 2 weeks after single or the last seizure, in case of epilepsy. The size of the X-ray hypoattenuation zone was compared on computed tomographic (CT) scans, performed in the weeks after the stroke and 1 week after single or repeated seizures. Lesion size was determined by superimposing the CT slices on digital cerebral vascular maps, on which the contours of the infarct area were delineated. The extent of the infarcts was expressed as the percentage fraction of the total surface area of the cerebral hemisphere. Groups with a single seizure and with epilepsy were mutually compared. Infarcts predominated in the parieto-temporal cortical regions. In the overall group the median Rankin score worsened significantly after seizures. The average size of the X-ray hypoattenuation zone was also significantly increased on the CT scans after the seizures, compared with those after stroke, without clear evidence of recent infarction. Mutual comparison of patients with a single seizure episode and of those with epilepsy showed only a trend of more severe disability and of increase in lesion size in the post-stroke epilepsy group. Delayed seizures and epilepsy after ischaemic stroke are accompanied by an increase in lesion size on CT and by worsening of the disability of the patients. This study does not allow to determine whether this is due to stroke recurrence or due to additional damage as a result of the seizures themselves. 相似文献
20.
David Mechanic 《Social science & medicine (1982)》1992,34(12):1345-1350
Health is a product of culture and social structure. The routine organization and constraints of everyday settings shape our health. Socio-economic status is of major importance in determining exposure to disease risk and in shaping health and illness behavior responses. Lay explanations of illness affect illness appraisal, self-treatment, decisions to seek care and changes in daily regimen. Somatization of psychosocial stressors is a common concern in primary care systems throughout the world, and doctors are commonly frustrated by such patients. Somatizing patients are often enmeshed in environments of great psychosocial difficulty or are depressed, and many cultural and social factors affect how depression is expressed. Although depression has devastating disabling effects on patients, it is often neither recognized by doctors nor treated. But doctor-patient relationships are often the context for appropriate management of such problems, and how they are handled affect the future trajectory of illness and disability. Doctors' responses are conditioned by their attitudes, training, interviewing and psychosocial skills, and organizational and financial factors. Patient flow is an important intervening variable affecting the management of psychosocial difficulties and depression. 相似文献