Frontotemporal dementia subtypes based on behavioral inhibition deficits

Abstract

Introduction We aimed to investigate phenotypic heterogeneity in the behavioral variant of frontotemporal dementia (bvFTD) through assessment of inhibition deficits. Methods We assessed occurrences of 16 behavioral inhibition deficits from video recordings of 15 bvFTD patients (early stage) and 15 healthy controls (HC) in an ecological setting. We extracted dimensions of inhibition deficit and analyzed their correlations with cognitive and clinical measures. Using these dimensions, we isolated patient clusters whose atrophy patterns were explored. Results After identifying two patterns of inhibition deficit (compulsive automatic behaviors and socially unconventional behaviors), we isolated three behavioral clusters with distinct atrophy patterns. BvFTD‐G0 (N = 3), an outlier group, showed severe behavioral disturbances and more severe ventromedial prefrontal cortex/orbitofrontal cortex atrophy. Compared to bvFTD‐G1 (N = 6), bvFTD‐G2 (N = 6) presented higher anxiety and depression along with less diffuse atrophy especially in midline regions. Discussion Identifying clinico‐anatomical profiles through behavior observation could help to stratify bvFTD patients for adapted treatments.

Functional Connectivity Correlates of Reduced Goal-directed Behaviors in Behavioural Variant Frontotemporal Dementia

“…The data gathered for this article are part of the ECOCAPTURE protocol (Clinicaltrials.gov:NCT02496312; see Batrancourt et al (Batrancourt et al 2019) and Supplementary file 1 Part A for further details on this protocol) designed to investigate the behavioral signature and mechanisms of neuropsychiatric syndromes such as apathy or disinhibition (Godefroy et al 2021). For this study, we used data allowing to investigate the behavioral signature and mechanisms of apathy: behavioral measures collected with an ecological approach, clinical measures of apathy (by questionnaires) and MRI data.…”

An ecological approach to identify distinct neural correlates of disinhibition in frontotemporal dementia

“…Taking these limitations and considerations into account, we recently proposed a behavioural study using an ecological paradigm mimicking a real-life situation, under controlled conditions and a structured scenario (ECOCAPTURE, FRONTlab, ICM), to identify objectively and quantify behavioural disorders, such as apathy and disinhibition ( Batrancourt et al, 2019 , Godefroy et al, 2021 ). We have previously proposed a precise description of behavioural disinhibition in bvFTD based on the literature review ( Paholpak et al, 2016 , Rascovsky et al, 20112011 , Snowden et al, 2001 ) which involves a list of 16 behaviours of interest potentially observable in the context of the ECOCAPTURE scenario.…”

“…We have previously proposed a precise description of behavioural disinhibition in bvFTD based on the literature review ( Paholpak et al, 2016 , Rascovsky et al, 20112011 , Snowden et al, 2001 ) which involves a list of 16 behaviours of interest potentially observable in the context of the ECOCAPTURE scenario. In this previous study, we distinguished three disinhibition categories: compulsivity , impulsivity and social disinhibition ( Godefroy et al, 2021 ). We found that a bivariate model fit the data from our bvFTD patients well, defining a two-dimensional structure for the classification of behaviours related to inhibition deficits.…”

“…Thus, based on the literature and our previous work ( Godefroy et al, 2021 ), we decided for the present study to focus on these two subtypes of inhibition deficits, which seem particularly relevant for the exploration and characterization of disinhibition in bvFTD patients. Compulsivity involves dysfunctional inhibition of thoughts and behaviour and could be defined as “actions inappropriate to the situation which persist, have no obvious relationship to the overall goal and which often result in undesired consequences” ( Dalley et al, 2011 ), and it often results in an inability to flexibly adapt behaviours and/or switch attention between stimuli ( Fineberg et al, 2014 , Fineberg et al, 20182018 ).…”

“…We hypothesised that: 1) our semi-ecological approach would be able to differentiate bvFTD patients and HC on the basis of two different subtypes of behavioural disinhibition previously established ( Godefroy et al, 2021 ), 2) these subtypes would be associated with distinct cognitive measures of inhibition deficits; and 3) these subtypes would be related to different neural networks, in term of grey and white matter.…”