title: Verbal working memory performance correlates with regional white matter structures in the frontoparietal regions.
abstract: Working memory is the limited capacity storage system involved in the maintenance and manipulation of information over short periods of time. Previous imaging studies have suggested that the frontoparietal regions are activated during working memory tasks; a putative association between the structure of the frontoparietal regions and working memory performance has been suggested based on the analysis of individuals with varying pathologies. This study aimed to identify correlations between white matter and individual differences in verbal working memory performance in normal young subjects. We performed voxel-based morphometry (VBM) analyses using T1-weighted structural images as well as voxel-based analyses of fractional anisotropy (FA) using diffusion tensor imaging. Using the letter span task, we measured verbal working memory performance in normal young adult men and women (mean age, 21.7 years, SD=1.44; 42 men and 13 women). We observed positive correlations between working memory performance and regional white matter volume (rWMV) in the frontoparietal regions. In addition, FA was found to be positively correlated with verbal working memory performance in a white matter region adjacent to the right precuneus. These regions are consistently recruited by working memory. Our findings suggest that, among normal young subjects, verbal working memory performance is associated with various regions that are recruited during working memory tasks, and this association is not limited to specific parts of the working memory network.
authors: Smart Ageing International Research Center, Institute of Development, Aging and Cancer, Tohoku University, Aoba-ku, Sendai, Japan. takehi@idac.tohoku.ac.jp
authors: Hikaru
authors: H
authors: Takeuchi
authors: Yasuyuki
authors: Y
authors: Taki
authors: Yuko
authors: Y
authors: Sassa
authors: Hiroshi
authors: H
authors: Hashizume
authors: Atsushi
authors: A
authors: Sekiguchi
authors: Ai
authors: A
authors: Fukushima
authors: Ryuta
authors: R
authors: Kawashima
mesh_terms: D000328:Adult; D016880:Anisotropy; D001931:Brain Mapping; D056324:Diffusion Tensor Imaging; D005260:Female; D005625:Frontal Lobe / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009413:Nerve Fibers, Myelinated / Q000502:physiology*; D009483:Neuropsychological Tests; D010296:Parietal Lobe / Q000033:anatomy & histology* / Q000502:physiology; D013223:Statistics as Topic; D014706:Verbal Learning / Q000502:physiology*; D055815:Young Adult