What it is:
  • Motor Neuron Disease consists of a group of diseases which progressively damage and destroy motor neurons.
  • This means that the motor neurons cannot transmit impulses from the brain or spinal cord to the muscles to instruct them to move.
  • The muscles therefore cannot function; resulting in the weakening of muscles; muscle atrophy (loss of muscle mass and the wasting away of muscles); fasciculations (uncontrollable muscle twitching); muscle spasticity (excessive contraction of the muscles resulting in tightness or stiffness); and difficulty speaking, breathing and swallowing.
  • The sufferer eventually loses the ability to control all voluntary muscle movement.
  • The sufferer's mental functioning and senses are not affected by the disease.
  • The disease is progressive, meaning that the degeneration (breaking down) of neurons and the deterioration of muscles becomes worse over time.
  • There are different types Motor Neuron Disease; and they are classified according to which motor neurons they affect.
  • Some affect the motor neurons coming from the spinal cord and the lower parts of the brain (lower motor neurons); and others affect the motor neurons coming from the upper parts of the brain (upper motor neurons).
  • The most common Motor Neuron Disease is called Amyotrophic Lateral Sclerosis. It affects upper and lower motor neurons.

Muscle atrophy due to Motor Neuron Disease
Muscle atrophy due to Motor Neuron Disease

Upper and Lower Motor Neurons and some of the muscles which they affect
Upper and Lower Motor Neurons and some of the muscles which they affect

  • Motor Neuron Disease can be hereditary, but only about 10% of all cases are hereditary.
  • There are some factors which are thought to cause the disease by damaging the neurons, such as:
    • Cancer.
    • Too much exposure to toxins in drugs or in the environment.
    • An inadequate production of the molecules which help the growth and repair of neurons (called neurotrophic factors). This makes the neurons more susceptible to damage.
    • An excess of the neurotransmitter, glutamate, in the body. Too much glutamate is toxic and damages important parts of the brain and spinal cord; which disrupts the communication between neurons.
    • Cells between the neurons in the brain (Glia cells), which provide support, insulation and nutrients to the neurons, are problematic.
  • However, the exact cause of the disease is unknown.

The symptoms depend on the type of Motor Neuron Disease the sufferer has. The most usual symptoms for a person with the common Motor Neuron Disease (Amyotrophic Lateral Sclerosis) are below.
  • In the early stages:
    The muscles of the hands, feet, arms and legs are usually affected first. The disease then spreads to other parts of the body.
    • weakened grip and difficulty holding objects
    • muscle pain
    • cramps and twitches (fasciculations)
    • slurred and muddled speech
    • weak limbs (arms and legs)
    • clumsiness; falling down; and tripping
  • In the advanced stages:
    • muscles of the arms and legs start to shrink (atrophy) and become weaker
    • the initial symptoms worsen
    • difficulty with swallowing and breathing
    • drooling
  • In the final stages:
    • paralysis
    • breathing problems worsen
    • eventually, death occurs
  • Mental functioning, vision, hearing, sense of smell and taste are usually unaffected; therefore, the person is fully aware of what is happening to their body.

Cure and Treatment:
  • There is no cure for the disease.
  • A drug (called Riluzole) can slow down the progression of the disease to prolong the sufferer's life by a few months.
  • The sufferer will need help and care from different types of doctors and medical workers. For example:
    • General practitioner
    • Neurologist
    • Occupational therapist
    • Physiotherapist
    • Speech therapist
    • Home care nurses
  • Other treatment relieves the symptoms of the disease to make the sufferer more comfortable, such as:
    • Medication to relax the muscles (which may be stiff) and relieve muscle pain.
    • Physical, occupational and speech therapy to improve posture and speech, slow down the muscle weakening, keep the muscles flexible, and keep the joints mobile.
    • Braces (hold parts of the body upright), speech synthesisers (a type of computer that artificially produces speech), ventilator systems (to help with breathing), gastrostomies (feeding tubes), and wheelchairs may also be used.
A patient using a ventilator system to help with breathing
A patient using a ventilator system to help with breathing
Professor Stephen Hawking uses a voice synthesiser to communicate, and is permanently in a wheelchair
Professor Stephen Hawking uses a voice synthesiser to communicate, and is permanently in a wheelchair

  • The disease becomes worse as it progresses (i.e. the muscles deteriorate continually).
  • Most Motor Neuron Diseases are fatal - the sufferer eventually becomes paralysed and dies.
  • Death is normally due to the intercostal muscles of the lungs failing, so the person cannot breathe.
  • The life expectancy of a person with the disease is 1-5 years.

  • Motor Neuron Disease is uncommon. It affects about 5 out of 100 000 people worldwide.
  • The disease affects people worldwide.
  • It is more common among adult men, but women and children can get it too.

  • For adults, the symptoms start appearing between 40-60 years of age.

  • For children, the symptoms start appearing between birth and 1 year of age.

  • There is no prevention for Motor Neuron Disease.

The sufferer's experience:
  • The sufferers experience many emotional and psychological effects of the disease. These are:
    • Isolation
    • Exclusion
    • Low self-esteem
    • Anxiety
    • Frustration
    • Loss of independence
    • Depression
  • At home:
    • The person will need to make their home more suitable to their disease. They may install things such as:
    • Handrails in the bathroom and seats in the shower
    • Velcro on their clothing so that they can dress and undress easily
    • Hands-free telephones
    • Portable panic alarms
    • Voice or remote controlled lights and electronic equipment
  • When the condition becomes very bad, the person will be fully dependent on home care nurses to help them with daily activities. These care-givers will make sure that the sufferer is as comfortable as possible by helping the sufferer with:
    • Dressing
    • Washing
    • Sitting in comfortable positions
    • Moving around
  • Financial Support:
    • In some countries such as Australia and the United Kingdom, Motor Neuron Disease Associations offer loans and equipment to sufferers.
    • The South African government provide disability grants to people who cannot afford the care themselves
  • Public awareness of the disease:
    • Motor Neuron Disease is not well known disease as it is an uncommon disease. Many people are not aware of the disease or of how serious it is.
    • However, the sufferers need a lot of support from their communities and the public because of the devastating physical and emotional effects of the disease.

      Read the blog of a sufferer of Motor Neuron Disease

Famous people with Motor Neuron Disease:
  • Stephen Hawking:
    • He is a world famous theoretical physicist and author.
    • He was diagnosed with Motor Neuron Disease in 1963 and was given two and a half years to live.
    • However, he still managed to become a researcher and professor at Cambridge; he has written many books on his scientific theories about the universe; and he is still alive today despite his disease.

  • Joost van der Westhuizen:
    • He is a former Springbok rugby player who was diagnosed with Motor Neuron Disease in May 2011.
    • He has been given 2-5 years to live.
Stephen Hawking in his wheelchair with his voice synthesiser
Stephen Hawking in his wheelchair with his voice synthesiser

Joost van der Westhuizen
Joost van der Westhuizen

Watch a video of Tony Judt, a historian and author, speaking about living with motor neuron disease:

Websites accessed:,62813.asp