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Alzheimer's Disease Health Center

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Glossary of Alzheimer's Disease Terms


Music therapy: Use of music to improve physical, psychological, cognitive, and social functioning.

Nerve cell (neuron): The basic working unit of the nervous system. Nerve cells send signals that control the actions of other cells in the body, such as other nerve cells and muscle cells.

Nerve cell transplantation: An experimental procedure in which normal brain cells are implanted into diseased areas of the brain to replace dying or damaged cells.

Nerve growth factor (NGF): A protein that promotes nerve cell growth and may protect some types of nerve cells from damage.

Neuritic plaque: See amyloid plaque.

Neurodegenerative disease: A type of neurological disorder marked by the loss of nerve cells. (See Alzheimer's disease and Parkinson's disease.)

Neurofibrillary tangle: An accumulation of twisted protein fragments inside nerve cells. Neurofibrillary tangles are one of the characteristic structural abnormalities found in the brains of people with Alzheimer's disease. The presence of amyloid plaques and neurofibrillary tangles discovered at autopsy is used to positively diagnose Alzheimer's disease.

Neurological disorder: A disturbance in structure or function of the nervous system resulting from developmental abnormality, disease, injury, or toxin.

Neurologist: A doctor who is specially trained to diagnose and treat disorders of the nervous system.

Neuron: See nerve cell.

Neuropathology: Changes in the brain produced by a disease.

Neuropsychological testing: The evaluation of brain function and an individual's capabilities that uses tests to assess language, visual-perceptual skills, memory, attention, problem-solving, and reasoning.

Neuropsychologist: An individual who holds a doctoral degree (PhD or PsyD) in clinical psychology or a related discipline and who specializes in the evaluation and management of brain dysfunction.

Neurotransmission: The passage of signals from one nerve cell to another via chemical substances or electrical signals.

Neurotransmitter: A special chemical in the brain that is necessary for communication between nerve cells. Examples of neurotransmitters include acetylcholine, dopamine, norepinephrine, and serotonin.

Nucleus: The central component of a cell containing all genetic material.

Occupational therapists: Health care professionals that teach people how to return to normal activities after injury or illness using therapy and rehabilitation.

Onset: Defines the time when a disease begins (early onset, late-onset).

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