title: Person-Based Versus Generalized Impulsivity Disinhibition in Frontotemporal Dementia and Alzheimer Disease.
abstract: BACKGROUND
  While much disinhibition in dementia results from generalized impulsivity, in behavioral variant frontotemporal dementia (bvFTD) disinhibition may also result from impaired social cognition.
  
  
  OBJECTIVE
  To deconstruct disinhibition and its neural correlates in bvFTD vs. early-onset Alzheimer's disease (eAD).
  
  
  METHODS
  Caregivers of 16 bvFTD and 21 matched-eAD patients completed the Frontal Systems Behavior Scale disinhibition items. The disinhibition items were further categorized into (1) "person-based" subscale which predominantly associated with violating social propriety and personal boundary and (2) "generalized-impulsivity" subscale which included nonspecific impulsive acts. Subscale scores were correlated with grey matter volumes from tensor-based morphometry on magnetic resonance images.
  
  
  RESULTS
  In comparison to the eAD patients, the bvFTD patients developed greater person-based disinhibition ( P < 0.001) but comparable generalized impulsivity. Severity of person-based disinhibition significantly correlated with the left anterior superior temporal sulcus (STS), and generalized-impulsivity correlated with the right orbitofrontal cortex (OFC) and the left anterior temporal lobe (aTL).
  
  
  CONCLUSIONS
  Person-based disinhibition was predominant in bvFTD and correlated with the left STS. In both dementia, violations of social propriety and personal boundaries involved fronto-parieto-temporal network of Theory of Mind, whereas nonspecific disinhibition involved the OFC and aTL.
authors.affiliation: 1 Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA.|2 Department of Psychiatry, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Pongsatorn
authors.initials: P
authors.lastname: Paholpak
authors.affiliation: 1 Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA.|3 Greater Los Angeles VA Healthcare System, West Los Angeles, CA, USA.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Carr
authors.affiliation: 3 Greater Los Angeles VA Healthcare System, West Los Angeles, CA, USA.
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Barsuglia
authors.affiliation: 1 Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA.|3 Greater Los Angeles VA Healthcare System, West Los Angeles, CA, USA.
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Barrows
authors.affiliation: 1 Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA.|3 Greater Los Angeles VA Healthcare System, West Los Angeles, CA, USA.|4 Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California at Los Angeles, CA, USA.
authors.forename: Elvira
authors.initials: E
authors.lastname: Jimenez
authors.affiliation: 5 Department of Psychology, School of Behavioral Health, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Grace J
authors.initials: GJ
authors.lastname: Lee
authors.affiliation: 1 Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA.|3 Greater Los Angeles VA Healthcare System, West Los Angeles, CA, USA.|4 Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California at Los Angeles, CA, USA.
authors.forename: Mario F
authors.initials: MF
authors.lastname: Mendez
keywords: Alzheimer disease; Frontal System Behavior Scale; disinhibition; frontotemporal dementia