Diagnosing dementia and determining what type it is can be challenging. A diagnosis of dementia requires that at least two core mental functions be impaired enough to interfere with daily living. They are memory, language skills, ability to focus and pay attention, ability to reason and problem-solve, and visual perception.

Your doctor will review your medical history and symptoms and conduct a physical examination. He or she will likely ask someone close to you about your symptoms, as well.

No single test can diagnose dementia, so doctors are likely to run a number of tests that can help pinpoint the problem.

Cognitive and neuropsychological tests

Doctors will evaluate your thinking (cognitive) function. A number of tests measure thinking skills such as memory, orientation, reasoning and judgment, language skills, and attention.

Neurological evaluation

Doctors evaluate your memory, language, visual perception, attention, problem-solving, movement, senses, balance, reflexes and other areas.

Brain scans

  • CT or MRI. These scans can check for evidence of stroke or bleeding or tumor or hydrocephalus.
  • PET scans. These can show patterns of brain activity and if the amyloid protein, a hallmark of Alzheimer's disease, has been deposited in the brain.

Laboratory tests

Simple blood tests can detect physical problems that can affect brain function, such as vitamin B-12 deficiency or an underactive thyroid gland. Sometimes the spinal fluid is examined for infection, inflammation or markers of some degenerative diseases.

Psychiatric evaluation

A mental health professional can determine whether depression or another mental health condition is contributing to your symptoms.

April 05, 2016
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