Verbal training can improve neurocognitive and reading performance by increasing white matter integrity and grey matter volume

Ching-Chi Hsu; Yun-Hsiang Wu; Kang-Shuo Lee; Po-Cheng Shih; Tzu-Yu Liu; James Cheng-Chung Wei; Wei-Min Chu; Toshiharu Nakai; Fan-Pei Gloria Yang

doi:10.1016/j.exger.2024.112625

Verbal training can improve neurocognitive and reading performance by increasing white matter integrity and grey matter volume

Exp Gerontol. 2024 Nov 9:198:112625. doi: 10.1016/j.exger.2024.112625. Online ahead of print.

Authors

Ching-Chi Hsu¹, Yun-Hsiang Wu², Kang-Shuo Lee², Po-Cheng Shih³, Tzu-Yu Liu², James Cheng-Chung Wei⁴, Wei-Min Chu⁵, Toshiharu Nakai⁶, Fan-Pei Gloria Yang⁷

Affiliations

¹ Board of Directors, Wizcare Medical Corporation Aggregate, Taichung, Taiwan; International Intercollegiate Ph.D. Program, National Tsing Hua University, Hsinchu, Taiwan.
² Department of Foreign Languages and Literature, National Tsing Hua University, Hsinchu, Taiwan; Center for Cognition and Mind Sciences, National Tsing Hua University, Hsinchu, Taiwan.
³ Division of Allergy, Immunology, Rheumatology, Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan; Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan.
⁴ Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan; Department of Allergy, Immunology & Rheumatology, Chung Shan Medical University Hospital, Taichung, Taiwan; Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan.
⁵ Department of Family Medicine, Taichung Veterans General Hospital, Taichung, Taiwan; School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan; Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan; Geriatrics and Gerontology Research Center, College of Medicine, National Chung Hsing University, Taichung, Taiwan. Electronic address: williamchu0110@gmail.com.
⁶ Department of Radiology, Graduate School of Dentistry, Osaka University, Suita, Japan; Institute of Neuroimaging and Informatics, Obu, Japan. Electronic address: nakai.niinf@gmail.com.
⁷ Department of Foreign Languages and Literature, National Tsing Hua University, Hsinchu, Taiwan; Center for Cognition and Mind Sciences, National Tsing Hua University, Hsinchu, Taiwan; Department of Radiology, Graduate School of Dentistry, Osaka University, Suita, Japan. Electronic address: fpyang@faculty.hss.nthu.edu.tw.

PMID: 39490557
DOI: 10.1016/j.exger.2024.112625

Abstract

Introduction: Dementia and mild cognitive impairment (MCI) present both health and economic challenges on a global scale, thus affecting millions of people, and is projected to increase significantly by the year 2050. Early language processing deficits are evident in those diagnosed with Alzheimer's disease and MCI. Recent advances in pharmacologic and non-pharmacologic interventions, including cognitive rehabilitation and training, show promising effects on cognitive functions. Articulation training, particularly, is highlighted for its potential in addressing the communication difficulties which those experiencing dementia and MCI face, based on the transmission deficit hypothesis. This study aimed to perform a voxel-wise comparison of morphological changes in grey matter volume as well as white matter integrity to represent the plastic changes in response to articulation training among older, healthy Japanese adults.

Methods: Forty older, healthy Japanese adults were randomized into either a cognitive training group or a control group. The study involved comprehensive behavioral assessments, neuroimaging (including 3D anatomy, fMRI and Diffusion Tensor Imaging), and a structured verbal articulation training regimen. The training included reading tasks which focused on enhancing both articulation and phonological skills. Neuroimaging data were acquired using a 3 Tesla Siemens MR scanner, with the FSL tool being used for white matter analysis and the CAT12 toolbox for grey matter analysis.

Results: Significant increases in grey matter volume were observed in certain regions, including the left Supplementary motor area, Postcentral gyrus, and bilateral Superior frontal gyrus among those in the training group. Correlations were noted between reading abilities and cortical volume in areas such as the left Middle temporal gyrus, pulvinar, and Middle occipital gyrus. White matter integrity also improved, as evidenced by increased fractional anisotropy in tracts such as the superior longitudinal fasciculus, corona radiata, and internal capsule. These findings suggest a link between articulation training and enhanced neuroplasticity in both grey and white matter regions related to language processing.

Conclusion: The study demonstrates that a 4-week verbal articulation training intervention period can lead to significant improvements in grey matter volume in the left Supplementary motor area, the left Postcentral gyrus, and the bilateral Superior frontal gyrus, as well as the integrity of white matter tracts associated with language processing among older adults. These results suggest that such training could be a valuable tool in enhancing cognitive functions related to language in older populations.