We know that certain environmental substances can trigger autoimmune disease. For example, silica can trigger scleroderma; certain drugs can trigger lupus; and, in some women, pregnancy can trigger an autoimmune disease. For more information: http://www.aarda.org/modules.php.
UPPER MOTOR NEURON DISORDERS (UMN). An upper motor neuron starts in the motor cortex of the brain and terminates within the medulla (another part of the brain) or within the spinal cord.So, an UMN disorder would include injury, disease or disturbance within this pathway from or within the brain and to the spinal cord (Photo 6).PPER MOTOR NEURON DISORDERS (UMN). An upper motor neuron starts in the motor cortex of the brain and terminates within the medulla (another part of the brain) or within the spinal cord.
Causes of motor neurone disease. Motor neurone disease occurs when specialist nerve cells (motor neurones) in the brain and spinal cord progressively lose their function.It's not clear why this happens. In most cases, a person with motor neurone disease won't have a family history of the condition. This is known as sporadic motor neurone disease.auses of motor neurone disease. Motor neurone disease occurs when specialist nerve cells (motor neurones) in the brain and spinal cord progressively lose their function.