The Frontal Systems Behavior Scale discriminates frontotemporal dementia from Alzheimer's disease.

Frontotemporal dementia (FTD) is characterized by pronounced changes in affect, self-regulation, and social conduct. These behaviors can predate significant cognitive changes and can be the most disabling aspect of FTD, yet there are few scales designed to assess such changes. The Frontal Systems Behavior Scale (FrSBe) is a 46-item behavior rating scale that is intended to measure behavior associated with damage to the frontal systems of the brain, with subscales measuring Apathy, Disinhibition, and Executive Dysfunction. Thirty-four FTD patients and 34 matched patients with dementia of the Alzheimer's type (DAT) were compared on the FrSBe in the present study. Both groups displayed increases in apathy and dysexecutive behaviors after the onset of dementia, but the FTD group exhibited significantly greater change in disinhibition. A discriminant analysis with just two scores from the FrSBe and a memory test correctly classified 81% of the patients into diagnostic group.