Neuropsychological Testing to Evaluate Alzheimer's Disease

Clock Drawing Test and Other Neuropsychological Tests

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 person that specializes in understanding the relationship between the brain, behavior, and functioning of an individual.

Here are just a few of the neuropsychological tests used to better understand Alzheimer's disease and other forms of dementia

ADAS-Cog (Alzheimer's Disease Assessment Scale-Cognitive)

Alzheimer's Patient
Alzheimer's Patient. David Ramos / Stringer / Getty Images

This is an 11-part test that takes 30 to 45 minutes to complete and is considered more thorough than the Mini-Mental State Exam. It's generally used in the mild to moderate stage of Alzheimer's disease, to assess their level of cognitive impairment, once they have been diagnosed. The ADAS-Cog focuses on attention, language, orientation, executive functioning, and memory skills.

Short Blessed Test

This test is sometimes called the Orientation-Memory-Concentration test. It contains six items and evaluates orientation, registration, and attention.

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. It also assesses memory, concentration, and information processing. In this test, a person is asked to draw the face of a clock, including all of twelve 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.

Neuropsychiatric Inventory (NPI)

The NPI is particularly useful in differentiating a healthy person from a person with dementia. It's administered to caregivers and is able to screen not only for Alzheimer's disease, but other forms of dementia as well. 

The NPI assesses several neuropsychiatric problems commonly seen in Alzheimer's disease and other types of dementia, including agitation, anxiety, apathy, delusions, hallucinations, eating difficulties, mood problems, disinhibition, irritability, unusual motor or movement activity, and night-time disturbances.

Alzheimer's Disease-8 (AD8)

The AD8 is a "yes" or "no" question-based tool that can be administered to a caregiver or a patient. Its purpose is to differentiate mild dementia from those without dementia. The AD8 consists of 8 questions that focus on performance, like trouble learning how to use an appliance, and memory, like forgetting appointments or repeating questions. If a person or their caregiver (preferred) answers "yes" to 2 or more questions, they are considered at high risk for cognitive impairment. 

What Does This All Mean for Me or My Loved One?

Neuropsychological testing shouldn't be used independently to make a diagnosis — they are helpful tools that can help better understand a person's symptoms. A diagnosis of Alzheimer's can only be made after a complete diagnostic workup rules out any other possible causes.

Sources:

Alzheimer's Association. (2015). Tests for Alzheimer's Disease and Dementia. Retrieved November 21st 2015. 

American Psychological Association. (2015). Neuropsychiatric Inventory. Retrieved November 21st 2015. 

Carpenter CR et al. Four sensitive screening tools to detect cognitive dysfunction in geriatric emergency department patients: brief Alzheimer’s screen, short blessed test, Ottawa 3DY, and the caregiver-completed AD8. Acad Emerg Med.  2011 Apr;18(4):374-84. 

Cummings, J. L., Mega, M., Gray, K., Rosenberg-Thompson, S., Carusi, D. A., & Gornbein, J. (1994). The Neuropsychiatric Inventory: Comprehensive assessment of psychopathology in dementia. Neurology, 44(12), 2308-2314.

Dementia Collaborative Research Centres. Cognition Assessment Measures. Retrieved November 21st 2015.

Nesset M, Kersten H, & Ulbstein ID. Brief Tests such as the Clock Drawing Test or Cognistat Can Be Useful Predictors of Conversion from MCI to Dementia in the Clinical Assessment of Outpatients. Dement Geriatr Cogn Dis Extra. 2014 May-Aug;4(2):263-70.

Ueckert S et al. Improved Utilization of ADAS-Cog Assessment Data Through Item Response Theory Based Pharmacometric Modeling. Pharm Res. 2014;31(8):2152-2165.

University of Iowa. Clock Drawing Test. Retrieved November 21st 2015. 

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