A Neurodegenerative Disease is a condition in which cells of the brain and spinal cord are lost. The brain and spinal cord are composed of neurons that provide different functions such as controlling movements, processing sensory information, and making decisions. Cells of the brain and spinal cord are not readily regenerated, so when they are damaged or diseased their damage can be devastating.
Neurodegenerative diseases result from a deterioration of neurons or their myelin sheath, which over time will lead to dysfunction and disability.
The following conditions are the more common Neurodegenerative Diseases:
Alzheimer's Disease: This is a common, progressive degenerative disease that usually manifests itself with subtle memory loss and forgetfulness. It frequently progresses to impair an individual's capacity for independent thought and function. It is characterized by abnormal accumulations of amyloid-beta protein.
Parkinson's Disease: This is a common, progressive neurodegenerative disorder caused by degeneration of neurons that produce the neurotransmitter dopamine. It is characterised by tremor, slowed movement, stiffness and difficulty walking. It is associated with abnormal accumulations of alpha-synuclein protein.
Multiple Sclerosis: The most frequent cause of nontraumatic neurologic disability arising in young adulthood, this autoimmune neurodegenerative disease is triggered by genetic and environmental factors. It is associated with the destruction of neuronal myelin sheaths.
Huntington's Disease: Huntington's disease (HD) is a fatal disease with profound neurological and behavioural features. HD is typically characterised by uncontrollable movements and psychological disturbances. It is caused by a detectable genetic mutation that can be passed from generation to generation.
Amyotrophic Lateral Sclerosis (ALS/Lou Gehrig's Disease): ALS is a fatal neurodegenerative disease that results from the death of motor neurons. A progressive loss of muscle control impairs the individual's capacity for independent function.
Frontotemporal Dementia (Pick's Disease): Frontotemporal Dementia accounts for 18% of dementias in people under 65 years old. It frequently manifests itself as a behavioural disturbance, and can progress to impair an individual's capacity for independent thought and function. Recent studies have uncovered genetic factors that contribute to FTD, however no proven treatment options are yet established.
Prion Diseases: These are fatal neurodegenerative diseases caused by an agent known as a prion. Prions were discovered by Dr. Stanley Prusiner of the IND, who received a Nobel Prize for this work. Prions in animals cause diseases such as bovine spongiform encephalopathy, also known as "mad cow disease". In humans, they cause a rapidly progressive form of dementia known as Creutzfeldt-Jakob Disease (CJD).
HIV Associated Dementia: HIV Associated Dementia frequently appears in later stages of AIDS. It is usually associated with an increasing amount of HIV found in the blood, and a drop in the number of disease-fighting blood cells known as CD4 cells. Experts believe this group of symptoms occur as a result of HIV infection of the brain damaging the central nervous system, and in some cases the peripheral nerves.