The Impact of Cognitive Training on Cerebral White Matter in Community-Dwelling Elderly: One-Year Prospective Longitudinal Diffusion Tensor Imaging Study.

Xinyi Cao,Wei Feng,Yan Cheng,Qingwei Li,Yuan Shen,Lijuan Jiang,Jianfeng Feng,Ting Li,Jijun Wang,Chunbo Li,Jianhua Sheng,Ye Yao,Wenyuan Wu

doi:10.1038/srep33212

Abstract

It has been shown that cognitive training (CogTr) is effective and recuperative for older adults, and can be used to fight against cognitive decline. In this study, we investigated whether behavioural gains from CogTr would extend to white matter (WM) microstructure, and whether training-induced changes in WM integrity would be associated with improvements in cognitive function, using diffusion tensor imaging (DTI). 48 healthy community elderly were either assigned to multi-domain or single-domain CogTr groups to receive 24 sessions over 12 weeks, or to a control group. DTI was performed at both baseline and 12-month follow-up. Positive effects of multi-domain CogTr on long-term changes in DTI indices were found in posterior parietal WM. Participants in the multi-domain group showed a trend of long-term decrease in axial diffusivity (AD) without significant change in fractional anisotropy (FA), mean diffusivity (MD) or radial diffusivity (RD), while those in the control group displayed a significant FA decrease, and an increase in MD and RD. In addition, significant relationships between an improvement in processing speed and changes in RD, MD and AD were found in the multi-domain group. These findings support the hypothesis that plasticity of WM can be modified by CogTr, even in late adulthood.

Highlights

It has been shown that cognitive training (CogTr) is effective and recuperative for older adults, and can be used to fight against cognitive decline
Because differences related to handedness, as confounders in white matter, might have affected the results of the diffusion tensor imaging (DTI) indices[26,27], two left-handed participants were excluded from the analysis
A total of 48 right-handed participants were used in this DTI analysis (17 in the multi-domain CogTr group, 17 in the single-domain group and 14 in the control group)

Summary

Introduction

It has been shown that cognitive training (CogTr) is effective and recuperative for older adults, and can be used to fight against cognitive decline. We investigated whether behavioural gains from CogTr would extend to white matter (WM) microstructure, and whether training-induced changes in WM integrity would be associated with improvements in cognitive function, using diffusion tensor imaging (DTI). Significant relationships between an improvement in processing speed and changes in RD, MD and AD were found in the multi-domain group These findings support the hypothesis that plasticity of WM can be modified by CogTr, even in late adulthood. Fractional anisotropy (FA) and mean diffusivity (MD) are the two most commonly used indices to assess white matter integrity, as derived from DTI While the former is a scalar value that refers to the coherence of the direction of water diffusion, the latter is the mean rate of free water diffusion across all three eigenvalues, representing the overall strength of water mobility in different regions of the brain[7]. The former indicates axonal morphology, while the latter signifies the character of the myelin[8,9]

Methods

Results

Conclusion