What is dementia?

Dementia is a non-specific clinical syndrome that involves cognitive impairments of sufficient severity to interfere with social or occupational functioning. It involves at least two areas of affected cognition – memory, language, reasoning, attention, perception, or problem solving. Memory loss alone is not necessarily dementia as there can be many causes of memory loss. Among the most common types of dementia are Alzheimer’s disease, Lewy body dementia, frontotemporal dementia, and vascular dementia.

What causes dementia?

Dementia is caused by structural abnormalities in the brain tissue. Multiple biological factors (e.g. plasma tau protein, amyloid plaques) and environmental factors (e.g. repeated head trauma, drug abuse) contribute to dementia. Diseases such as Alzheimer’s, Parkinson’s, AIDS, Syphilis, brain tumors, and metabolic disorders are causes of dementia. Excessive alcohol and drug consumption, severe vitamin deficiencies, as well as multiple head traumas such as repeated concussions can also contribute to dementia.

How is dementia diagnosed?

Dementia is diagnosed through evaluation of the patient’s medical history (e.g. medications, recent illnesses) and multiple additional tests including behavioral tests, memory evaluation, lab tests, and interviews of family members about recent changes in thinking and day-to-day function. While doctors can diagnose with a high level of certainty the presence of dementia, the exact type of dementia or its likely progression can be harder to determine.

How does dementia relate to aphasia?

Most aphasia types are caused by stroke or other acute brain injury that damages brain tissue in areas important for language processing. However, a type of aphasia called primary progressive aphasia is a neurodegenerative disease, which results from progressive deterioration of brain tissue in areas important for speech and language. It is often caused by diseases such as s Alzheimer’s or Frontotemporal Lobar Degeneration. Although the first symptoms are problems with speech and language, other problems associated with the underlying disease, such as memory loss and personality changes often occur later. Learn more about diagnosing PPA and managing PPA.

More dementia and PPA resources