Neuropsychological profiles of dementia syndromes

by Zakzanis, Konstantine K.

The purpose of this investigation was to place diagnostic science on fimer foundations by using effect size summaries of relevant literature to underpinthe selection and interpretation of test instruments in the field of dementia Accordingly, the neuropsychologicalfiterature on dementia was systematicaliy reviewed and all relevant findings were converted into effect sizes. Meta-analytic methodology was employed to synthesize these effects &O pronles. The pronles provide a quantitativeevaluation of individual test sensitivitiesto different dementia syndromes. By generating preserved and irnpaired ability profiles fiom different dementia syndromes, it was found that certain neuropsychoIogical tasks and test variables correspond to effect sizes with "marker" sensitivitycapable of discriminating ail patients in a given sample fiom all healthy normal control comparisons. These cognitive markers were used to formulate empiricaily valid clinical and research test batteries for each of the dementia syndromes considered here. Based on these test batteries, it is also imptied that dementia syndromes can be differentiated based on test sensitivitygiven preserved and impaired abiiity profiles by the process of double dissociation. Together, the hdings provide the cllliician and researcher neuropsychological profiles that cm aid in the recognition and differential diagnosis of dementia syndromes.