In the Alzheimer's Series:

• An Introduction to Alzheimer's
• Symptoms of Alzheimer's Disease
• Causes of Alzheimer's
• Treatment of Alzheimer's
• How Alzheimer's is Diagnosed
• What is the Outlook for Alzheimer's?
• Further Information

Alzheimer's disease is characterized by the development of multiple cognitive deficits manifested by:

• Memory impairment (impaired ability to learn new information or to recall previously learned information)
• And one (or more) of the following cognitive disturbances:
  • Deterioration of language may be manifested by difficulty producing the names of individuals and objects (aphasia)
  • An impaired ability to carry out motor activities (such as combing their hair) despite intact motor abilities, sensory function and comprehension of the required task (apraxia)
  • A failure to recognize or identify objects despite intact sensory function (agnosia)
  • A disturbance in executive functioning (e.g., planning, organizing, sequencing, abstracting)

The cognitive deficits above each cause significant impairment in social or occupational functioning and represent a significant decline from a previous level of functioning. The course is characterized by gradual onset and continuing cognitive decline. The deficits do not occur exclusively during the course of a delirium.

The cognitive deficits above are not due to any of the following:

• Other central nervous system conditions that cause progressive deficits in memory and cognition (e.g., cerebrovascular disease, Parkinson's disease, Huntington's disease, subdural hematoma, normal-pressure hydrocephalus, brain tumor)
• Systemic conditions that are known to cause dementia (e.g., hypothyroidism, vitamin B-12 or folic acid deficiency, niacin deficiency, hypercalcemia, neurosyphilis, HIV infection)
• substance-induced conditions

Last reviewed:
  On 12 Oct 2006
  By John M. Grohol, Psy.D.