Motor Health Dictionary

A group of disorders of unknown origin. Certain cells in the neurological system’s MOTOR nerves degenerate and die. Upper and lower motor neurones may be affected but sensory cells retain their normal functions. Three types of MND are identi?ed: amyotrophic lateral sclerosis (AML – 50 per cent of patients); progressive muscular atrophy (25 per cent), in which the prognosis is better than for AML; and bulbar palsy (25 per cent). Men are affected more than women, and the disorder affects about seven people in every 100,000. Those affected develop progressive weakness and wasting of their muscles. The diagnosis is con?rmed with various tests including the measurement of electrical activity in muscles, electromyography, muscle BIOPSY, blood tests and X-ray examination of the spine. There is no medical treatment: patients need physical and psychological support with aids to help them overcome disabilities. The Motor Neurone Disease Association provides excellent advice and help for sufferers and their relatives. (See APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELF-HELP.)... motor neurone disease (mnd)

A group of disorders in which there is degeneration of the nerves in the central nervous system that control muscular activity. This causes weakness and wasting of the muscles. The cause is unknown.

The most common type of motor neuron disease is amyotrophic lateral sclerosis ( or Lou Gehrig’s disease). It usually affects people over the age of 50 and is more common in men. Some cases run in families. Usually, symptoms start with weakness in the hands and arms or legs, and muscle wasting. There may be irregular muscle contractions, and muscle cramps or stiffness. All four extremities are soon affected.

Progressive muscular atrophy and progressive bulbar palsy both start with patterns of muscle weakness different from but usually develop into.There are 2 types of motor neuron disease that first appear in childhood or adolescence. In most cases, these conditions are inherited. Werdnig–Hoffman disease affects infants at birth or soon afterwards. In almost all cases, progressive muscle weakness leads to death within several years. Chronic spinal muscular atrophy begins in childhood or adolescence, causing progressive weakness but not always serious disability.

There are no specific tests for motor neuron disease. Diagnosis is based on careful clinical examination by a neurologist. Tests including EMG, muscle biopsy, blood tests, myelography, CT scanning, or MRI may be performed.

The disease typically goes on to affect the muscles involved in breathing and swallowing, leading to death within 2–4 years. However, about 10 per cent of sufferers survive for 10 years.

Nerve degeneration cannot be slowed down, but physiotherapy and the use of various aids may help to reduce disability. The drug riluzole is used to extend life (or the time until mechanical ventilation is required).... motor neuron disease

the region of the *cerebral cortex that is responsible for initiating nerve impulses that bring about voluntary activity in the muscles of the body. It is possible to map out the cortex to show which of its areas is responsible for which particular part of the body. The motor cortex of the left cerebral hemisphere is responsible for muscular activity in the right side of the body.... motor cortex

one of the nerves that carry impulses outwards from the central nervous system to bring about activity in a muscle or gland. Compare sensory nerve.... motor nerve

one of the units (*neurons) that goes to make up the nerve pathway between the brain and an effector organ, such as a skeletal muscle. An upper motor neuron has a cell body in the brain and an axon that extends into the spinal cord, where it ends in synapses. It is thus entirely within the central nervous system. A lower motor neuron, on the other hand, has a cell body in the spinal cord or brainstem and an axon that extends outwards in a cranial or spinal motor nerve to reach an effector.... motor neuron