[Neuropsychology of frontal type dementia]

The clinical conceptual change in frontal type dementia is reviewed in discussing its relationships to several related concepts such as Pick's disease, frontotemporal dementia (FTD), semantic dementia (SD) and frontotemporal lobar degeneration. We analyzed frontal type dementia selected from a consecutive series of our outpatients as to the details of neuropsychological symptoms, psychiatric symptoms, and abnormal behaviors. In our series of 143 patients with primary degenerative dementia, there were 16 cases of FTD and 6 cases of SD. Patients with two types of FTD and patients with SD were not distinguishable by neuropsychological examinations, behavioral abnormalities and psychiatric symptoms assessed with the Neuropsychiatric Inventory except for aphasia. The clinical picture of frontal type dementia involves frontal lobe symptoms such as disinhibition, apathy and stereotypy. Semantic memory loss for words, objects or faces suggestive of temporal lobe involvement developed only in patients with SD, and not in patients with FTD. Certain behavioral symptoms seen in frontal type dementia may respond to selective serotonin reuptake inhibitors. In care for patients with frontal type dementia, behavioral disturbances can be diminished and the quality of life can be improved by using their preserved procedural memory, pathological stereotypic behavior and stimulus-bound behavior such as utilization behavior and environmental dependency syndrome.