The cortical lesion pattern of Dysexecutive syndrome in MEMENTO cohort

International audienceObjective: The objective of this study was to investigate the association between cortical thickness and executive functions in the Memento Cohort.Background: Dysexecutive disorders are one early sign of Alzheimer’s disease (AD). Their precise cortical lesion patterns still remain undetermined. Memento cohort is a large French cohort with extensive clinical, neuropsychological and neuroimaging data for studying the natural history of AD in a large group of participants with different subtypes of mild cognitive impairment or isolated subjective cognitive complaints.Design/Methods: We selected from the Memento cohort (Dufouil et al., 2017) all subjects with available region of interest (ROI) cortical thickness data and executive function (verbal fluency and trail making test (TMT)) assessment (n=1924 out of N=2323). Mean MMSE was 28.02 (±1.6), 59.8 % of participants had a Clinical Dementia Rating scale of 0.5, 62.1 % were women. Stepwise linear regression adjusted on age, and education level were achieved to determine reduced brain parenchymal fraction (BPF) and decrease of cortical thickness regions related to both verbal fluency (literal and semantic) and time difference of TMT part B and part A performance (TMTB-At).Results: Semantic fluency was related to BPF and cortical thickness of right supramarginal, right cingulate isthmic and left entorhinal regions (R$^2$=0.133, p=0.0001). Literal fluency was related to BPF and cortical thickness of left pars orbitalis region (R$^2$=0.162, p=0. 0001). TMTB-At was related to cortical thickness of right precuneus and right isthmic cingulate regions (R$^2$=0.142, p=0.0001).Conclusions: The cortical lesion pattern of executive functions was the right supramarginal, right cingulate isthmic, left entorhinal regions, left pars orbitalis and right precuneus. To our knowledge this is the first study to determine precisely, from a large cohort with standardized assessments, the cortical regions related to executive performance