Glossary of Dementia Terms


Dementia symptoms show up in loss of memory, movement disorders, and changes in the person’s language, judgment, and behavior.

The different types of dementia have:
Different causes
Slightly different symptoms

Agnosia
inability to comprehend, sense, or recognize things (including sounds) usually as a consequence of brain damage. More
Agraphia
neurological disorder causing a declinee in ability to communicate through writing. Writing skill may represent procedural memory, and agraphia errors indicate alterations in long-term memory
Alpha-synuclein
protein found in the brain and other parts of the body. Synucleinopathies aggregates form in Lewy bodies.
Alzheimer’s disease
the most common cause of dementia in older adults. Alzheimer’s disease is characterized by high levels of amyloid plaques and tau tangles in the brain but these cannot be found until the brain is examined in an autopsy.
Amyloid
a protein that aggregates to form plaques that appear in the brains of people with Alzheimer’s disease.
Alpha-synuclein
protein found in the brain and other parts of the body. Synucleinopathies aggregates form in Lewy bodies.
Aphasia
loss of comprehension and/or communication by one or more means. Aphasia is caused by neural dysfunctions.
Ataxia
loss of coordination in body movements
behavioral frontotemporal dementia (bvFTD)
neurodegenerative disease caused by damage to the prefrontal cortex
Cognitive reserve
term used in aging literature to refer to the ability of the brain to bounce back after minor brain damage or physical decline in brain functins do to aging. Different people perform mental tasks in different ways and some are more resilient than others. A person with high cognitive reserve shows fewer symptoms from brain damage or disease.
Corticobasal degeneration
breakdown of the cerebral cortex and basal ganglia and the symptoms and disorder that manifest in patients. Autopsies find patients’ brains have atrophied and buildup of the protein tau..
Dementia
syndrome marked by impaired memory and other cognitive dysfunction.
Encephalitis
inflammation of the brain.
Frontotemporal disorders
degeneration of the frontal and temporal lobes of the brain and dementia caused by it.
Lewy body dementia
common form of dementia characterized by abnormal structures called Lewy bodies in the brain.
Mild Cognitive Impairment
some loss in memory or reasoning ability but not to the point of dementia. Sometimes considered the "prodrome" of dementia.
Mixed dementia
when the patient has one form of dementia and another condition or dementia at the same time
Multi-infarct dementia (MID)
dementia caused by numerous small strokes.
Neurocognitive disorder
Non-psychiatric illness that results in decreased mental functioning. Formerly used to indicate dementia, or in the classification of the American Psychiatric Association’s Diagnostic Manual IV "Dementia, Delirium, Amnestic, and Other Cognitive Disorders".
Neurodegeneration
the progressive loss of nerve cell function.
Neurofibrillary tangles
bundles of protein filaments (tau proteins). Prevalent in the brains of people with Alzheimer’s disease.
Paradoxial Lucidity
phenomena seen in late-stage dementia patients in which the person's symptoms subside and they become briefly lucid. More.
Parkinson’s disease dementia
a dementia that sometimes occurs in patients with Parkinson’s disease.
Plaques
abnormal clumps of amyloid protein that are found in large numbers in the brains of people with Alzheimer’s disease.
Reminiscence
palliative nursing technique to calm patients and promote a sense of wellbeing by reminding people about other points in their lives.
Tau
a protein that helps the functioning of microtubules, which are part of the cell’s structural support and help deliver substances throughout the cell. In several dementia disorders, tau twists into filaments that become tangles.
Tauopathies
Disorders associated with an accumulation of tau in the brain.
Vascular dementia
a type of dementia caused by brain ischemia (strokes).