| 摘要: | 連續表現任務（Continuous performance task , CPT）是一種評估注意力相關問題的臨床試驗。在CPT過程中，行為數據（如反應時間、正確率）和神經元訊號數據（如P3振幅）都可以被測量，並用於提供與注意力有關的疾病的診斷。過去研究指出注意力測驗中，腦波中P300振幅越高表示注意力越集中。在頻域方面，也有研究指出在注意力下降時Theta頻帶(4-7Hz) 會提高，Beta頻帶(13-30Hz)會降低，及theta/beta比值會增加。通常，CPT是在控制良好的實驗環境下給予受試者的，沒有考慮到可能意外發生的干擾的影響。在這項研究中，我們通過使用虛擬實境（virtual reality ,VR）來構建一個具有多種干擾模式的教室場景，研究環境干擾是否會對注意力產生影響。
我們招募了30名健康男性受試者。他們被要求在三維VR環境下執行GO/NO-GO任務，測試中GO條件為數字1後面為0時要按下板機，NO-GO條件則是1後面不為0而不要按板機，GO的發生機率為20%，藉此發生注意力P300波，本研究在整個任務過程中以500Hz的採樣率記錄了6通道EEG(Cz,Pz,C3,C4,FCz,CPz)和2通道EOG，並分析在執行專注力試驗時的腦波資料做時域和頻域訊號的比較。分析結果顯示，在比較NO-GO試驗時，當受試者注意目標時（即"GO"的條件），干擾的呈現導致了Pz電極P3振幅和所有電極β功率的顯著增加，但 Cz 處的 P3 幅度和 Cz、FCz 處的 theta 功率顯著降低。與無干擾試驗相比，在 go 條件下的干擾試驗中，所有電極的 theta 和 beta 功率顯著更大。 對於NO-GO條件，與無干擾相比，干擾增強了所有電極的 beta 功率。GO和NO-GO條件之間 P3 幅度的差異驗證了該 VR 系統探測注意力的有效性。增強 theta 和 beta 功率表明環境干擾引起了更多與注意力相關的神經元資源。
總之，環境干擾會影響注意力的神經元活動，這一發現可用於設計治療方案，以提高注意力相關疾病的治療效果。
;The Continuous Performance Task (CPT) is a clinical trial that assesses attention-related problems. During CPT, behavioral data (such as reaction time, accuracy) and neuronal signal data (such as P3 amplitude) can be measured and used to provide a diagnosis of attention-related disorders. Previous studies have shown that higher P300 amplitude in brain waves indicates higher attention in attention tests.In terms of frequency domain, it has also been suggested that the Theta band (4-7Hz) increases and Beta band (13-30Hz) decreases when attention decreases, and theta/beta ratio increases. Usually, CPT is given to subjects under a well-controlled experimental environment and does not take into account the effect of interference which may occur un-expectedly. In this study, we examine whether the environmental interference can have any impact on attention by using virtual reality (VR) to construct a classroom scene with multiple modes of interferences.
We recruited 30 healthy male subjects. They were asked to perform a GO/NO-GO task in a 3D VR environment, where the GO condition was to press the board when the number 1 was followed by 0, and the NO-GO condition was not to press the board when the number 1 was not followed by 0. The probability of GO was 20%, whereby a P300 wave of attention occurred.In this study, six channels of EEG (Cz, Pz, C3, C4, FCz, CPz) and two channels of EOG were recorded at a sampling rate of 500 Hz throughout the task, and brain wave data were analyzed for comparison of time domain and frequency domain signals during the execution of the attention test. The analytic results exhibited that, when compared with the no-go conditions, the presents of interferences resulted in significant increase in P3 amplitudes at Pz and the beta power of all channels but significant decrease in P3 amplitudes at Cz and the theta power at Cz and FCz when the subjects have payed attention on the cues (i.e. the “go” condition). When compared with no interference trials, the theta and beta power at all channels were significantly greater in interference trials under the go condition. For no-go conditions, the interference enhanced the beta power at all channels when compared with no interference.
The differences in P3 amplitudes between go and no-go conditions validated the efficacy of this VR system to probe the amount of attention. The enhancement of the theta and beta power with inference suggested that environmental distractions elicited greater attention-related neuronal resources.
In conclusion, the environmental interference can affect the neuronal activities for attention and this finding can be used to design the therapeutic protocol to promote the treatment efficacy of attention-related disorders. |
