碩士 / 國立台北護理學院 / 聽語障礙科學研究所 / 94 / The neurophysiological model postulates that the limbic and autonomic nervous systems are involved in mechanisms responsible for emergence of tinnitus and hyperacusis, meanwhile hyperacusis was considered as “pre-tinnitus status”. The purpose of the present study was to clarify the neurophysiological mechanism of tinnitus and hyperacusis. The premise of the study is to gain the highest spatial resolution, the most robust responses, and the shortest experimental time in high scanner noise environment of fMRI.
It is a concern about the cortical activation regions of tinnitus and hyperacusis patients elicited by auditory stimulation using BOLD functional MRI. We use (1) 5 normal controls to investigate the cortical activation of different auditory stimuli (classical music, ocean waves, engineer noise, white noise and 1000Hz pure tone), different matrix sizes (64×64, 128×128) and different intensity to get the most optimal fMRI parameters and auditory stimulus in pilot study, (2) 12 normal controls to explore the activation regions of white noise binaurally , (3) 3 tinnitus and hyperacusis patients to probe the activation regions of white noise binaurally.
The result of this qualitative pilot study demonstrated that the most optimal parameters were the white noise, 128×128 matrix size and 80-curve when compared to other auditory stimuli. Since white noise stimulation elicited activation of bilateral Heschl’s gyrus (HG) in normal controls. Under uniformed white noise stimuli, the first tinnitus patient revealed activation among multiple brain areas including HG, but not the limbic system. However, parahippocampal gyrus was activated during auditory stimulation in both the second and the third hyperacusis patients. These results suggest that the cortical activation patterns in response to loud sound are abnormal in tinnitus and hyperacusis patients. Our results were consistent with the neurophysiological model of tinntius and hyperacusis.
Identifer | oai:union.ndltd.org:TW/094NTCN0714004 |
Date | January 2006 |
Creators | Pao-Hsuan Chou, 周寶宣 |
Contributors | Tien-Chen Liu, 劉殿楨 |
Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
Language | zh-TW |
Detected Language | English |
Type | 學位論文 ; thesis |
Format | 140 |
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