Effects of ageing and Alzheimer disease on haemodynamic response function: a challenge for event-related fMRI

Healthcare Technology Letters

article

Davud Asemani¹  Hassan Morsheddost²  Mahsa Alizadeh Shalchy² 

[1] Division of Radiology, Medical University of South Carolina;Biomedical Engineering Department, K. N. Toosi University of Technology

关键词: diseases;    haemodynamics;    biomedical MRI;    neurophysiology;    deconvolution;    geriatrics;    signal denoising;    medical signal processing;    ageing;    Alzheimer disease;    haemodynamic response function;    event-related fMRI;    functional magnetic resonance imaging;    brain images;    neuronal activity;    HRF;    blood-oxygenation;    deconvolution;   

DOI  :  10.1049/htl.2017.0005

学科分类：肠胃与肝脏病学

来源: Wiley

【 摘 要 】

Functional magnetic resonance imaging (fMRI) can generate brain images that show neuronal activity due to sensory, cognitive or motor tasks. Haemodynamic response function (HRF) may be considered as a biomarker to discriminate the Alzheimer disease (AD) from healthy ageing. As blood-oxygenation-level-dependent fMRI signal is much weak and noisy, particularly for the elderly subjects, a robust method is necessary for HRF estimation to efficiently differentiate the AD. After applying minimum description length wavelet as an extra denoising step, deconvolution algorithm is here employed for HRF estimation, substituting the averaging method used in the previous works. The HRF amplitude peaks are compared for three groups HRF of young, non-demented and demented elderly groups for both vision and motor regions. Prior works often reported significant differences in the HRF peak amplitude between the young and the elderly. The authors’ experimentations show that the HRF peaks are not significantly different comparing the young adults with the elderly (either demented or non-demented). It is here demonstrated that the contradictory findings of the previous studies on the HRF peaks for the elderly compared with the young are originated from the noise contribution in fMRI data.

【 授权许可】

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