21 research outputs found
Visual Feedback Postural Control Re-education
No full textMaintaining postural stability is a complex process [1] involving the coordinated actions of biomechanical, sensory, motor, and central nervous system components. A relatively simple biomechanical definition for postural stability can be formulated in terms of the position of the body center of gravity relative to the base of support. The body movements used to maintain postural stability, however, are complex because of the number of joint systems and muscles involved. The center of gravity (CoG) is the point at which the whole weight of a body may be considered to act. In humans who are standing quietly and vertically erect, the CoG is located at the level of the hips and slightly forward of the ankle joints. CoG height is 0.5527 of total height. CoG and center of mass (CoM) are equivalent points in space when the gravitational field is uniform and gravity is the only force under consideration
Aging and vestibular system: specific tests and role of melatonin in cognitive involvement
No full textBalance disorders are frequent with aging. They are particularly important because they decrease social autonomy of the aged subjects and they often provoke falls. The cause is always multifactorial. There is evidence that aging affects multiple sensory inputs, as well as the muscoloskeletal system and central nervous system ability to perform sensorimotor integration. For the evaluation of decreased balance skills in elderly, a specific questionnaire has been prepared, in order to identify high risk of falling called falling risk inventory (FRI) questionnaire, and a complex psycho-sensory-motor test has been studied by means of posturography, in order to detect specific vestibular impairment. Regarding ethiopathogenesis of balance disorders in aged subjects, because the decline of behavioral and cognitive performances are due also to decline of biological rhythm control, the role of melatonin (the hormone regulating circadian rhythms, being strictly connected with cerebellar function, and it is well known that cerebellum acts in elderly both at motor and cognitive regulation. The goals of the present paper are: (i) To present a self-administered FRI questionnaire aimed at identifying possible causes of falls and quantifying falling risk in aged. (ii) To validate posturography as a specific test to investigate vestibular involvement in elderly in correlation with FRI. (iii) To present a complex behavioral test (NT) aimed at evaluating both spatial orientation and spatial memory in elderly, factors involved into the genesis of complex dizziness and unsteadiness. (iv) To evaluate the role of melatonin in cognitive involvement in dizzy, old subjects due to the functional correlations between circadian rhythms, cerebellum balance disturbances and cognitive disorders. General conclusions are: FRI correlates with falling risk. Posturography identifies specific vestibular impairments correlated to balance disorders and elderly falls. Spatial orientation is altered in about 40% of dizzy patients but no significant differences are revealed in melatonin rhythm. Spatial memory is highly altered only in subjects with inversion of circadian melatonin rhythm it is possible to hypothesize that the alteration of the normal circadian melatonin rhythm plays some role in the genesis of dizziness in a subpopulation of patients
Aging and vestibular system: specific tests and role of melatonin in cognitive involvement
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Contribution de la Posturologie à la Recherche et au Diagnostic de la Dyslexie et du Retard Cognitif
No full textAn Initial Evaluation of Work Fatigue and Circadian Changes as Assessed by Multiplate Posturography
No full text The sensitivity of postural responses to the effects of work fatigue and circadian changes was explored in a pilot study using a specific method of multiplate posturography based on the differential assessment of vertical pressure on four separate platforms for each heel and set of toes of each foot, respectively. 8 normal subjects, M.D.s, were given six posturographic examinations immediately before and after three 8-hr. work shifts in the emergency room of a major hospital in Tel-Aviv. 3 posturographic measures (stability, spectral power of postural sway at low frequency of 0.1–0.25 Hz, and unilateral weakening of heel-toe synchronisation) were significantly affected by work fatigue whilst also showing interaction with circadian rhythm. 2 additional measures (power of sway at high frequency of 1.00–3.00 Hz and dysharmonic distribution of weight over the four platforms) were not related to workload but showed significant circadian changes. These effects appeared only on positions involving restricted visual and somatosensory feedback causing vestibular stress. Results justify the application of multiplate posturography as an ancillary tool in measuring objectively the effects of fatigue and circadian changes as well as the interaction between endogenous chronobiological processes and their external conditioning factors (Zeitgebers). Pragmatic implications of the findings in the context of industrial medicine and interdisciplinary efforts to prevent road and air accidents are discussed. </jats:p
Toward a script theory of guidance in computer-supported collaborative learning
No full textThis article presents an outline of a script theory of guidance for computer-supported collaborative learning (CSCL). With its four types of components of internal and external scripts (play, scene, role, and scriptlet) and seven principles, this theory addresses the question how CSCL practices are shaped by dynamically re-configured internal collaboration scripts of the participating learners. Furthermore, it explains how internal collaboration scripts develop through participation in CSCL practices. It emphasizes the importance of active application of subject matter knowledge in CSCL practices, and it prioritizes transactive over non-transactive forms of knowledge application in order to facilitate learning. Further, the theory explains how external collaboration scripts modify CSCL practices and how they influence the development of internal collaboration scripts. The principles specify an optimal scaffolding level for external collaboration scripts and allow for the formulation of hypotheses about the fading of external collaboration scripts. Finally, the article points towards conceptual challenges and future research questions
Families' social backgrounds matter : socio-economic factors, home learning and young children's language, literacy and social outcomes
No full textParental support with children's learning is considered to be one pathway through which socio-economic factors influence child competencies. Utilising a national longitudinal sample from the Millennium Cohort Study, this study examined the relationship between home learning and parents' socio-economic status and their impact on young children's language/literacy and socio-emotional competence. The findings consistently showed that, irrespective of socio-economic status, parents engaged with various learning activities (except reading) roughly equally. The socio-economic factors examined in this study, i.e., family income and maternal educational qualifications, were found to have a stronger effect on children's language/literacy than on social-emotional competence. Socio-economic disadvantage, lack of maternal educational qualifications in particular, remained powerful in influencing competencies in children aged three and at the start of primary school. For children in the first decade of this century in England, these findings have equity implications, especially as the socio-economic gap in our society widens
Young pregnancy and motherhood: A discourse analysis of context and expertise
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Progressing into the 21st century young pregnancy and parenthood in the United Kingdom is a focus of political, media and public attention. The country is described as experiencing an epidemic, with the highest rates of young pregnancy and parenthood recorded in Western Europe. Statistics demonstrate that in 2000 38,690 under 18 year-olds in England became pregnant, of which 44.8% ended in legal termination. In light of this data, and within their remit to address the issue of Social Exclusion, New Labour commissioned a report into young pregnancy resulting in the development and implementation of the Teenage Pregnancy Strategy. The Strategy has two main aims; namely reducing the rates of young conceptions and providing better support and education for young parents. This thesis argues from a conceptual framework that questions the contested assumption that young pregnancy and parenthood is a problem. A literature review demonstrates a lack of representation of the voices and experiences of young mothers. This directs the research question to ask what is the experience of young mothers in their own words and placed within context? Critical Discourse Analysis is used to examine three examples of context shaping data that includes government policy, a newspaper article and a radio talk show programme. The analysis reveals discourses that suggest there is a right time and framework for motherhood. These discourses form a dialectical relationship with voices and experiences of young mothers that are analysed using Discourse Analysis. This analysis elicits two key central discourses permeating the experiences of young mothers that are the Good- Bad mother binary that informs and exacerbates experiences of maternal ambivalence. Moreover, these discourses inform the practice of discrimination against young mothers. The thesis concludes with a call to listen to the experiences of young mothers in order that their needs might be more fully understood. It suggests that discrimination against young mothers be incorporated into Equal Opportunity and Anti- Discrimination policy
