Alzheimer's Disease

There is no single diagnostic test that can diagnose Alzheimer's disease. The process involves several tests and may take more than a day. These tests make it possible to diagnosis Alzheimer's with an accuracy of about 90 percent.

There are two abnormal structures in the brain associated with Alzheimer's disease — amyloid plaques and neurofibrillary tangles:

  • Amyloid Plagues — Amyloid plaques are sticky clumps or patches of protein surrounded by the debris of dying nerve cells in the brain.
  • Neurofibrillary Tangles — These are the damaged remains of protein called tau, which are required for normal brain function. In Alzheimer's, threads of tau protein become twisted, which researchers believe may damage neurons and cause them to die.

Research has provided clues about why the neuron cells die, but scientists have not identified the role plaques and tangles play in the disease and if they're the key factors.


At the UCSF Memory and Aging Center, an assessment will involve neurologists, radiologists, pharmacists, nurses and other health professionals. The evaluation may include a series of test to measure memory, reasoning, vision-motor coordination and language skills. In addition, the evaluation may include:

  • Brain Scans — These tests will be performed to detect other possible causes of dementia such as stroke.
  • Interviews — An interview with the patient and another person close to the patient, such as a relative, spouse or close friend who can provide examples of memory loss and functional decline.
  • Laboratory Tests — Lab tests, such as blood and urine tests, may provide information about problems other than Alzheimer's that could cause dementia.
  • Medical History — Information about mental or physical conditions, prescription and nonprescription drug use, and family medical history will be gathered.
  • Mental Status — An evaluation will be conducted to assess sense of time and place; ability to remember, understand and communicate; and ability to do simple math problems.
  • Physical Exam — The patient's nutritional status, blood pressure and pulse will be assessed. Tests of sensation, balance and other functions of the nervous system also will be conducted.

  • Psychiatric Evaluation — An assessment of mood and other emotional factors that could cause dementia-like symptoms or may accompany Alzheimer's disease will be performed.

Reviewed by health care specialists at UCSF Medical Center.

Related Information

UCSF Clinics & Centers

Neurology and Neurosurgery

Memory and Aging Center
1500 Owens St., Suite 320
San Francisco, CA 94158
Phone: (415) 353-2057
Fax: (415) 353-8292
Appointment information