title: Is the left uncinate fasciculus associated with verbal fluency decline in mild Alzheimer's disease?
abstract: The association between verbal fluency deficit in Alzheimer's disease (AD) and deterioration of specific white matter (WM) tracts is currently not well understood. Using diffusion tensor imaging, we investigated a possible association between the left uncinate fasciculus, which has been implicated in word retrieval, and verbal fluency deficit in AD. A comparison of five properties of WM (fractional anisotropy, mode of anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity) in 28 mild AD patients and 26 age-, gender- and education-matched healthy controls revealed significant group differences in a range of WM tracts. Looking specifically at diffusion parameters' values for the left uncinate fasciculus and verbal fluency scores in the AD group, we observed a positive trend between the letter fluency scores and mode of anisotropy values (r= 0.36,p= 0.55). Thus, our data suggest more global WM damage in mild AD, which also includes damage to the left uncinate fasciculus. However, damage to this particular tract is not robustly associated with verbal fluency decline at this stage of disease.
authors.affiliation: University of the Basque Country (UPV/EHU), Vitoria, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
authors.forename: Vanja
authors.initials: V
authors.lastname: Kljajevic
authors.affiliation: DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Dyrba
authors.affiliation: DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany; Clinic for Psychosomatic and Psychotherapy Medicine Rostock, Rostock, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Kasper
authors.affiliation: DZNE, German Center for Neurodegenerative Diseases, Rostock, Germany; Clinic for Psychosomatic and Psychotherapy Medicine Rostock, Rostock, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Teipel
keywords: Diffusion tensor imaging (DTI); Uncinate fasciculus; Verbal fluency; White matter; mild Alzheimer's disease