April 20, 2004
A simple word test employed by doctors and psychologists may offer useful information for professionals who care for patients with Alzheimer's disease. Called the National Adult Reading Test, or NART, the test asks people to read a list of about 50 words, such as "ache" and "thyme," that do not follow the usual rules of pronunciation. People who pronounce most of the words correctly tend to have intact mental functioning and verbal intelligence skills.
Surprisingly, the ability to pronounce such words remains relatively intact into old age, even in people with Alzheimer's (at least in the mild to moderate stages of the disease). Scottish researchers gave the test to more than 500 elderly men and women, some of whom had Alzheimer's disease. They then compared the results to IQ tests that the same people had taken decades earlier, when they were 11 years old. Their scores as children correlated highly with their scores on the NART test as seniors even in those who were showing serious memory problems due to Alzheimer's.
Diagnosing Alzheimer's is a difficult process. Doctors commonly employ word and memory tests like the mini-mental state exam (MMSE) to measure mental skills and memory. Scoring poorly on such tests often suggests a diagnosis of dementia or other brain problems.
Although the MMSE tells a doctor whether a patient has dementia, it does not accurately tell how far the dementia has progressed. To do this, a doctor needs to know how "smart" the patient was before he or she became ill. The NART test, in contrast to the MMSE, offers important clues about an individual's innate language skills and verbal intelligence, and how "smart" they were before they became sick with Alzheimer's. Doctors can then estimate the severity of a patient's dementia. The NART findings also point out that even in moderately demented individuals some cognitive skills are preserved.
In an editorial accompanying the study, Dr. Douglas K. Detterman, Ph.D., of the department of psychology at Case Western Reserve University, frames the study in the case of a hypothetical question that might be asked by a patient before a medical procedure, "Doctor," the patient asks, "will I be able to play the piano?" The correct response, he answers humorously, is "Of course, provided you knew how to play the piano before."
The NART test offers important clues about whether someone with Alzheimer's could play the proverbial piano before they became ill.
For more on the diagnosis of Alzheimer's disease, visit the www.ALZinfo.org.
McGurn B, Starr JM, Topfer JA, et al: "Pronunciation of Irregular Words is Preserved in Dementia, Validing Premorbid IQ Estimation." Neurology, Volume 62, pages 1184-1186, April 2004.
Detterman DK: "Doctor, Will I Be Able to Play the Piano?" (editorial). Neurology 62: pages 1038-1039, April 2004.