Distinct Subtypes of Behavioral Variant Frontotemporal Dementia Based on Patterns of Network Degeneration.

Importance: Clearer delineation of the phenotypic heterogeneity within behavioral variant frontotemporal dementia (bvFTD) will help uncover underlying biological mechanisms and improve clinicians' ability to predict disease course and to design targeted management strategies.

Objective: To identify subtypes of bvFTD syndrome based on distinctive patterns of atrophy defined by selective vulnerability of specific functional networks targeted in bvFTD using statistical classification approaches.

Design, Setting And Participants: In this retrospective observational study, 90 patients meeting the Frontotemporal Dementia Consortium consensus criteria for bvFTD underwent evaluation at the Memory and Aging Center of the Department of Neurology at University of California, San Francisco.

Verbal creativity in semantic variant primary progressive aphasia.

Emergence of visual and musical creativity in the setting of neurologic disease has been reported in patients with semantic variant primary progressive aphasia (svPPA), also called semantic dementia (SD). It is hypothesized that loss of left anterior frontotemporal function facilitates activity of the right posterior hemispheric structures, leading to de novo creativity observed in visual artistic representation. We describe creativity in the verbal domain, for the first time, in three patients with svPPA.