Slow, progressive degeneration and eventually death of the motor neurons is the characteristic feature of this disease. The end organ function for example walking, talking swallowing etc., is the result of signals arising from the brain and being passed on to the neurons in the brain stem and the spinal cord.

Patients suffering from Motor neuron disease generally present with progressive weakness, the weakness may be in the upper limbs (arms), it may begin in the lower limbs (legs), it may also present with difficulty in swallowing resulting in drooling of saliva, or difficulty articulating. They may notice twitches in the muscles. The sensation is generally preserved. The weakness gradually increases in intensity disabling the patient and eventually results in difficulty in breathing.

Presently, there are no drugs to cure MNDs, the treatment approaches are generally to manage the symptoms. Stem cell therapy has been approved by the US FDA for the treatment of MND.

Motor neuron diseases include: Amyotrophic Lateral Sclerosis (ALS, Lou Gehrig disease), post-polio syndrome (PPS), primary lateral sclerosis (PLS), progressive muscular atrophy (PMA), pseudobulbar palsy (spastic), progressive bulbar palsy.