Pongsatorn Paholpak1,2, Andrew R Carr1,3, Joseph P Barsuglia3, Robin J Barrows1,3, Elvira Jimenez1,3,4, Grace J Lee5, Mario F Mendez1,3,4. 1. 1 Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, CA, USA. 2. 2 Department of Psychiatry, Khon Kaen University, Khon Kaen, Thailand. 3. 3 Greater Los Angeles VA Healthcare System, West Los Angeles, CA, USA. 4. 4 Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California at Los Angeles, CA, USA. 5. 5 Department of Psychology, School of Behavioral Health, Loma Linda University, Loma Linda, CA, USA.
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.
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.
Entities:
Keywords:
Alzheimer disease; Frontal System Behavior Scale; disinhibition; frontotemporal dementia
Authors: E van den Berg; J M Poos; L C Jiskoot; B Montagne; R P C Kessels; S Franzen; J van Hemmen; W S Eikelboom; E G C Heijboer; J de Kriek; A van der Vlist; F J de Jong; J C van Swieten; H Seelaar; J M Papma Journal: Assessment Date: 2021-04-15