title: The profile of executive functioning in amnestic mild cognitive impairment: disproportionate deficits in inhibitory control.
abstract: Amnestic mild cognitive impairment (aMCI) represents a group of individuals who are highly likely to develop Alzheimer's disease (AD). Although aMCI is typically conceptualized as involving predominantly deficits in episodic memory, recent studies have demonstrated that deficits in executive functioning may also be present, and thorough categorization of cognitive functioning in MCI may improve early diagnosis and treatment of AD. We first provide an extensive review of neuropsychology studies that examined executive functioning in MCI. We then present data on executive functioning across multiple sub-domains (divided attention, working memory, inhibitory control, verbal fluency, and planning) in 40 aMCI patients (single or multiple domain) and 32 normal elderly controls (NECs). MCI patients performed significantly worse than NECs in all 5 sub-domains, and there was impairment (>1.0 SD below the mean of NECs) in all sub-domains. Impairment on each test was frequent, with 100% of MCI patients exhibiting a deficit in at least one sub-domain of executive functioning. Inhibitory control was the most frequently and severely impaired. These results indicate that executive dysfunction in multiple sub-domains is common in aMCI and highlights the importance of a comprehensive neuropsychological evaluation for fully characterizing the nature and extent of cognitive deficits in MCI.
authors.affiliation: Department of Psychology/Centre for Research in Human Development, Concordia University, Montréal, Québec.
authors.forename: Erin K
authors.initials: EK
authors.lastname: Johns
authors.forename: Natalie A
authors.initials: NA
authors.lastname: Phillips
authors.forename: Sylvie
authors.initials: S
authors.lastname: Belleville
authors.forename: Diane
authors.initials: D
authors.lastname: Goupil
authors.forename: Lennie
authors.initials: L
authors.lastname: Babins
authors.forename: Nora
authors.initials: N
authors.lastname: Kelner
authors.forename: Bernadette
authors.initials: B
authors.lastname: Ska
authors.forename: Brigitte
authors.initials: B
authors.lastname: Gilbert
authors.forename: Fadi
authors.initials: F
authors.lastname: Massoud
authors.forename: Chloé
authors.initials: C
authors.lastname: de Boysson
authors.forename: Hilary D
authors.initials: HD
authors.lastname: Duncan
authors.forename: Howard
authors.initials: H
authors.lastname: Chertkow
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000209:etiology* / Q000523:psychology; D060825:Cognitive Dysfunction / Q000150:complications*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests