以虛擬實境動態駕駛系統進行駕駛員暈車狀態與腦波反應之關連性研究

Abstract

暈車是每個人共有的生活經驗，但顯少有研究探討暈車與腦波的關係。本論文以動態虛擬駕車之平台為基礎，用非侵入式的方式量測並探討腦波在駕駛員暈車時的變化。由虛擬實境場景配合史都華平台所發展出來的虛擬動態駕車環境，提供一個接近真實的駕駛環境，也是一個低成本、高安全的實驗環境。一般的暈眩實驗，均僅使用問卷來做為受測者主觀的暈車指標評定，個體間存在無法評估的差異性，而本論文同時參考受測者主觀的暈眩問卷分數及包括心電圖、胃電圖及皮膚電導的客觀生理反應，再將各指標數據交叉驗證，以確保受測者處於暈車狀態下。針對主客觀都有暈車反應的受測者腦波進行分析，首先，將去除雜訊的腦波以獨立成分析技術(ICA)分離出與暈車相關的獨立成分，再針對這些與暈車相關的獨立成分做頻譜分析。發現受測者在暈車現象產生時，在腦部頂葉 (parietal lobe)位置附近之獨立成分的10Hz或20Hz附近的活動能量明顯被抑制。根據實驗結果，本實驗成功的找出腦部與暈車高度相關的位置及其能量被抑制的現象。

The nausea-related Electroencephalogram (EEG) dynamics corresponding to motion sickness inclining tasks is studied in this thesis with the virtual-reality based dynamic driving environment. The VR-based dynamic driving environment provides the advantages of safety, low cost, and the realistic stimuli to the subjects. The Motion Sickness Questionnaire (MSQ) is designed and the physiological responses (including Electrocardiogram (EKG), Electrogastrography (EGG) and galvanic skin response) are recorded to assess the motion sickness. The EEG changes correlated to motion sickness will not only refer to the MSQ score, but the objective indices should also be involved for systematic evaluation. It was found from the result that the EGG signal is an efficient index, which is suitable for most of the subjects with excellent response time. The independent component analysis (ICA) combined with power spectral analysis is applied to investigate the EEG dynamics during the motion sickness. The experiment results demonstrated that the subjects have the power-suppressions in some specific frequency bands (10 Hz and/or 20 Hz) in the parietal lobe region. The nausea-related region and the nausea-influenced power spectrum suppression can be successfully obtained with our experimental results.