Life Sciences Term 2

Disorders of the CNS

Diseases of the Nervous system

Alzheimer’s Disease

• Alzheimer’s disease (AD) is the most common form of dementia
• Usually affecting people over 65, although some people may develop early-onset AD
• Characterized by a loss of neurons and synapses in the cortex of the brain, as well as the presence of clumps of proteins (amyloid plaques) and tangled bundles of fibers
• There is no cure for the disease, which is progressive and eventually leads to death
• Cause: Unknown
  
• Symptoms: The loss of brain function results in:
  
• Slower thinking
• Behaviour changes
• Confusion about events, time and places
• Difficulty recognizing people they know
• Difficulty speaking, swallowing and walking 
• Cure: None
  
• Treatment:
  
• Researchers are trying to find better ways to treat the disease, delay its onset  and prevent it from developing
• Stem-cell research and therapeutic cloning hold great potential for providing a cure for Alzheimer’s disease.

Multiple sclerosis

• Multiple sclerosis (MS) is a progressive, degenerative disorder of the central nervous system (CNS), including the brain, optic nerve and spinal cord
• MS commonly occurs between the ages of 20 – 40 and affects more women than men
• Multiple sclerosis means ‘many scars’, resulting in damage to the axon-coating myelin sheath of nerve cells in communication pathways
• Scattered patches of demyelination in the pathways make it impossible for messages to move these hard areas
• Cause: Auto-immune disease
  
• Symptoms: MS affects:
  
• Movement, feeling and co-ordination and balance
• Vision, tingling and numbness, muscle weakness and spasms
• Fatigue
• Bladder and bowel problems
• Pain
• Concentration and memory loss
• Mood swings
• Cure: None
  
• Management strategies:
• Healthy lifestyle
• Stem-cell research and biologically engineered production of interferons slow down the progress of the disease.