Neuropsychological testing is sometimes used in the evaluation of Alzheimer's disease to learn more about the nature and level of a person's impairment. The testing is often conducted by a neuropsychologist (a psychologist who specializes in the relationship between the brain, behavior, and functioning). Several tests are available that can narrow the range of possible diagnoses by producing test patterns that resemble Alzheimer's or other conditions. A neuropsychologist might use one test or a whole battery of them, depending on the individual. Some of the more common tests include:
ADAS-Cog (Alzheimer's Disease Assessment Scale-Cognitive)
An 11-part test that takes 30 minutes to complete and is considered more thorough than the Mini-Mental State Exam. The ADAS-Cog focuses on attention, language, orientation, executive functioning, and memory skills.Blessed Test
One of the older neuropsychological tests, the Blessed Test takes only 10 minutes and assesses memory, attention, concentration, and the ability to complete activities of daily living, such as bathing, dressing, grooming, and eating.CANTAB (Cambridge Neuropsychological Test Automated Battery)
This unique tool includes 13 interrelated computerized tests of memory, attention, and executive functioning. The battery is administered through a computer by using a touch-sensitive screen. Research has shown the CANTAB to be relatively unbiased regarding a person's language and culture. It's also been shown to be quite sensitive to early signs of Alzheimer's disease.Clock Drawing Test
Often used in combination with other neuropsychological tests, the Clock Drawing Test assesses visual-spatial impairment, or problems with perceiving objects correctly and misperceiving the relationship between objects. The person is asked to draw the face of a clock, including all of the numbers, and then draw clock hands to read a certain time. While paper and pencil are most commonly used to administer this test, some computer versions have been developed.Cognistat (Neurobehavioral Cognitive Status Examination)
The Cognistat assesses language, construction (the ability to copy or assemble items in a two- or three-dimensional space), memory, mathematical calculations, and reasoning/judgment. The test takes approximately 10 minutes when the person shows no cognitive impairment; for those who are cognitively impaired, the test can take 20 to 30 minutes.Neuropsychiatric Inventory (NPI)
The NPI assesses several neuropsychiatric problems commonly seen in Alzheimer's disease and other dementias, including agitation, anxiety, apathy, delusions, hallucinations, eating difficulties, and sleep disturbances.Neuropsychological testing shouldn't be used independently to make a diagnosis, nor should any other singular aspect of the diagnostic process, such as the Mini-Mental State Exam or a general physical. A diagnosis of Alzheimer's can only be made after a complete diagnostic workup rules out any other possible cause for the person's symptoms.
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Kiernan, R. J., Mueller, J., Langston, J. W., & Van Dyke, C. (1987). The Neurobehavioral Cognitive Status Examination: A brief but differentiated approach to cognitive assessment. Annals of Internal Medicine, 107, 481-485.
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