Exams and Tests

There is no definitive medical test that confirms cognitive decline or dementia in Parkinson disease. The most accurate way to measure cognitive decline is through neuropsychological testing.

• The testing involves answering questions and performing tasks that have been carefully designed for this purpose. It is carried out by a specialist in this kind of testing.
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• Neuropsychological testing addresses the individual’s appearance, mood, anxiety level, and experience of delusions or hallucinations.
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• It assesses cognitive abilities such as memory, attention, orientation to time and place, use of language, and abilities to carry out various tasks and follow instructions.
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• Reasoning, abstract thinking, and problem solving are tested.
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• Neuropsychological testing gives a more accurate diagnosis of the problems and thus can help in treatment planning.
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• The tests are repeated periodically to see how well treatment is working and check for new problems.

Imaging studies: Generally, brain scans such as CT scan and MRI are of little use in diagnosing dementia in people with PD. Positron-emission tomographic (PET) scan may help distinguish dementia from depression and similar conditions in PD.