Set-Shifting Ability Is Associated with Gray Matter Volume in Older People with Mild Cognitive Impairment

BACKGROUND/AIMS: An understanding of the association between gray matter volume and executive functioning could provide strategies to reduce dementia risk in older people with mild cognitive impairment (MCI). METHODS: In a cross-sectional analysis, we assessed executive functioning in 83 older people with MCI using three standard neuropsychological tests: set shifting (difference between Trail Making Test Parts B and A), working memory (difference between Digit Span forward and backward from the Wechsler Adult Intelligence Scale-IV), and selective attention/response inhibition (difference between the second and third conditions of the color- and picture-word Stroop test). Gray matter volume was computed from brain MRIs and SIENAX from FSL software. RESULTS: Gray matter volume was significantly associated with set-shifting performance after accounting for age, gender, body mass index, education, and global cognition (standardized β = −0.376, p = 0.001), but not with working memory or selective attention/response inhibition. CONCLUSION: The executive function of set-shifting ability was correlated with gray matter volume in older people with MCI.