- Email: [email protected]
54. What is the effect of multiple sclerosis on employment?
1544
Abstracts / Journal of Clinical Neuroscience 16 (2009) 1514–1546
of mixed axonal/demyelinating type. MRI of the brain showed posterior predominantly subcortical white matter hyperintensities on T2 and FLAIR images. The patient was treated with steroids, intravenous gammaglobulin and antibiotics. The patient made an uneventful recovery over 3 weeks. There are a handful of previous case reports in which cerebral lesions have been seen in acute GBS, one of whom was also found to have Mycoplasma. The question arises as to whether these cerebral changes represent associated central demyelination due to common antigen or cross-reactivity, or whether a second para-infectious phenomenon has occurred. doi:10.1016/j.jocn.2009.07.078
54. What is the effect of multiple sclerosis on employment? Clarke Glynnis 1, Anderson Tim 1, Pearson John 2, Mason Deborah 3, Taylor Bruce 4 1 Department of Medicine, University of Otago, Christchurch, New Zealand 2 Department of Public Health, University of Otago, Christchurch, New Zealand 3 Department of Neurology, Christchurch Hospital, Christchurch, New Zealand 4 Menzies Research Institute, University of Tasmania, Hobart, Australia
Introduction: Multiple sclerosis (MS) is the most common disabling neurological disease of young adults in Europe and North America. It has an extremely variable clinical course which may result in people living for many years with varying levels of disability. In 2006 a national prevalence study of multiple sclerosis was conducted in New Zealand to determine the extent, distribution and impact of the disease on patients in this country. Objective: To determine the impact multiple sclerosis has on a number of socio-economic factors including employment status. This study was run to coincide with the New Zealand census 2006, enabling comparison with the total New Zealand population. Methods: A cross-sectional study was conducted utilizing multiple sources of notification, including MS society and hospital databases, direct advertising and private practice records. A questionnaire was sent to each person in New Zealand with MS. The information collected included general demographics and data on education, work and income status. Results: 2055 people responded to the survey (71% response rate). In March 2006 the labour force participation rate in New Zealand was 68.1%, whereas the rate for people with MS was 37% (p < 0.0001). The results show that 58% of respondents were not currently employed, with 63% stating that their employment status had changed due to their MS. The median personal income for respondents aged 15 years and over with MS was $20,000, whereas the median personal income for the New Zealand population on census night was $24,400. However 50% of respondents had a tertiary qualification as compared with 40% of the New Zealand population. All age groups over 30 years with MS earned less than their New Zealand peers until they reached 70 years and over where there was a leveling out of income which can be attributed to universal access to the New Zealand Government Superannuation. Conclusions: These results show that multiple sclerosis is a disease which has a significant impact on people’s ability to participate in the workforce. The early adult onset and chronic progressive nature of the disease compounds the effect, decreasing the person’s ability to earn over time as compared with their peers in New Zealand.
Supported by: New Zealand HRC partnership funding grant with the National MS Society of New Zealand.
doi:10.1016/j.jocn.2009.07.079
55. Neural networks involved in the control of skilled movement: correlated spike activity in the primary motor area of the cerebral cortex Ghosh Soumya 1,2, Putrino David 1,2, Mastaglia Frank L 1 1
Centre for Neuromuscular & Neurological Disorders, University of Western Australia, QEII Medical Centre, Nedlands, WA 6009 2 School of Physiotherapy, Curtin University of Technology, Bentley, WA 6102, Australia Introduction: The motor areas of the cerebral cortex are important for the performance of skilled voluntary movement, and injury to these areas is frequently associated with loss of motor skill. Temporally correlated (synchronized) neural activity has been proposed to play a role in cooperative action of motor cortex neurons, and motor coordination. In order to study neural codes associated with coordination of skilled reaching movements, we examined task related and correlated spike activity of neurons in the primary motor cortex (MI) of cats. Materials & Methods: The experiments were approved by the Animal Ethics Committee of the University of Western Australia, and the National Health and Medical Research Council of Australia (NH& MRC) guidelines for the use of animals in experiments were followed throughout. Single unit activity was recorded from the motor cortex of cats through chronically implanted microelectrodes, while they performed a trained reaching and retrieval task. Microelectrodes were implanted into identified forelimb representation (shoulder, elbow, wrist or digits) of the motor cortex by prior stimulation mapping. Frame by frame analysis of video camera records of the task was used to time different stages of the task (premovement, reach, withdraw and feeding stages) and accurately relate neural activity to task stages. Temporal correlation between the spike activities of neurons was evaluated by shufflecorrected crosscorrelograms. Results: Over several months of recording, a variety of task related modulations of neural activities were observed in individual efferent zones. Temporally correlated spike activity was rarely seen when the animal sat quietly, but often during task performance. Positively correlated activity was frequently observed between neurons active during different movements (e.g. reaching and withdrawing the forelimb), and between neurons in different representation zones (shoulder, elbow, wrist and digits). Most cross correlograms had narrow peaks (<5 ms) and most peaks were centred on or close to zero latency (<2 ms). Discussion: This study found synchronization of action potentials among MI neurons specifically related to skilled motor tasks, and linking neurons controlling different aspects of the task. In previous anatomical studies we have found extensive interconnections between representations of digits, wri st, elbow and shoulder, within the forelimb motor area of MI. These local intra-cortical networks may play a role in synchronized spike activity and motor coordination. A better understanding of the neural codes associated with motor coordination is important for the development of cortically controlled limb prosthesis. doi:10.1016/j.jocn.2009.07.080
Abstracts / Journal of Clinical Neuroscience 16 (2009) 1514–1546
of mixed axonal/demyelinating type. MRI of the brain showed posterior predominantly subcortical white matter hyperintensities on T2 and FLAIR images. The patient was treated with steroids, intravenous gammaglobulin and antibiotics. The patient made an uneventful recovery over 3 weeks. There are a handful of previous case reports in which cerebral lesions have been seen in acute GBS, one of whom was also found to have Mycoplasma. The question arises as to whether these cerebral changes represent associated central demyelination due to common antigen or cross-reactivity, or whether a second para-infectious phenomenon has occurred. doi:10.1016/j.jocn.2009.07.078
54. What is the effect of multiple sclerosis on employment? Clarke Glynnis 1, Anderson Tim 1, Pearson John 2, Mason Deborah 3, Taylor Bruce 4 1 Department of Medicine, University of Otago, Christchurch, New Zealand 2 Department of Public Health, University of Otago, Christchurch, New Zealand 3 Department of Neurology, Christchurch Hospital, Christchurch, New Zealand 4 Menzies Research Institute, University of Tasmania, Hobart, Australia
Introduction: Multiple sclerosis (MS) is the most common disabling neurological disease of young adults in Europe and North America. It has an extremely variable clinical course which may result in people living for many years with varying levels of disability. In 2006 a national prevalence study of multiple sclerosis was conducted in New Zealand to determine the extent, distribution and impact of the disease on patients in this country. Objective: To determine the impact multiple sclerosis has on a number of socio-economic factors including employment status. This study was run to coincide with the New Zealand census 2006, enabling comparison with the total New Zealand population. Methods: A cross-sectional study was conducted utilizing multiple sources of notification, including MS society and hospital databases, direct advertising and private practice records. A questionnaire was sent to each person in New Zealand with MS. The information collected included general demographics and data on education, work and income status. Results: 2055 people responded to the survey (71% response rate). In March 2006 the labour force participation rate in New Zealand was 68.1%, whereas the rate for people with MS was 37% (p < 0.0001). The results show that 58% of respondents were not currently employed, with 63% stating that their employment status had changed due to their MS. The median personal income for respondents aged 15 years and over with MS was $20,000, whereas the median personal income for the New Zealand population on census night was $24,400. However 50% of respondents had a tertiary qualification as compared with 40% of the New Zealand population. All age groups over 30 years with MS earned less than their New Zealand peers until they reached 70 years and over where there was a leveling out of income which can be attributed to universal access to the New Zealand Government Superannuation. Conclusions: These results show that multiple sclerosis is a disease which has a significant impact on people’s ability to participate in the workforce. The early adult onset and chronic progressive nature of the disease compounds the effect, decreasing the person’s ability to earn over time as compared with their peers in New Zealand.
Supported by: New Zealand HRC partnership funding grant with the National MS Society of New Zealand.
doi:10.1016/j.jocn.2009.07.079
55. Neural networks involved in the control of skilled movement: correlated spike activity in the primary motor area of the cerebral cortex Ghosh Soumya 1,2, Putrino David 1,2, Mastaglia Frank L 1 1
Centre for Neuromuscular & Neurological Disorders, University of Western Australia, QEII Medical Centre, Nedlands, WA 6009 2 School of Physiotherapy, Curtin University of Technology, Bentley, WA 6102, Australia Introduction: The motor areas of the cerebral cortex are important for the performance of skilled voluntary movement, and injury to these areas is frequently associated with loss of motor skill. Temporally correlated (synchronized) neural activity has been proposed to play a role in cooperative action of motor cortex neurons, and motor coordination. In order to study neural codes associated with coordination of skilled reaching movements, we examined task related and correlated spike activity of neurons in the primary motor cortex (MI) of cats. Materials & Methods: The experiments were approved by the Animal Ethics Committee of the University of Western Australia, and the National Health and Medical Research Council of Australia (NH& MRC) guidelines for the use of animals in experiments were followed throughout. Single unit activity was recorded from the motor cortex of cats through chronically implanted microelectrodes, while they performed a trained reaching and retrieval task. Microelectrodes were implanted into identified forelimb representation (shoulder, elbow, wrist or digits) of the motor cortex by prior stimulation mapping. Frame by frame analysis of video camera records of the task was used to time different stages of the task (premovement, reach, withdraw and feeding stages) and accurately relate neural activity to task stages. Temporal correlation between the spike activities of neurons was evaluated by shufflecorrected crosscorrelograms. Results: Over several months of recording, a variety of task related modulations of neural activities were observed in individual efferent zones. Temporally correlated spike activity was rarely seen when the animal sat quietly, but often during task performance. Positively correlated activity was frequently observed between neurons active during different movements (e.g. reaching and withdrawing the forelimb), and between neurons in different representation zones (shoulder, elbow, wrist and digits). Most cross correlograms had narrow peaks (<5 ms) and most peaks were centred on or close to zero latency (<2 ms). Discussion: This study found synchronization of action potentials among MI neurons specifically related to skilled motor tasks, and linking neurons controlling different aspects of the task. In previous anatomical studies we have found extensive interconnections between representations of digits, wri st, elbow and shoulder, within the forelimb motor area of MI. These local intra-cortical networks may play a role in synchronized spike activity and motor coordination. A better understanding of the neural codes associated with motor coordination is important for the development of cortically controlled limb prosthesis. doi:10.1016/j.jocn.2009.07.080