以生理監測系統為基礎之合成化戰場作戰模擬訓練成效分析

Abstract

軍事作戰中，決策判斷是非常重要的能力，一個正確的決策可為團隊帶來極度正面的報酬與成就感，一個錯誤的決策可能帶來非常嚴重、萬劫不復的後果。因此每一個決策都是至關重要，除了對個體的影響外，也會影響到整個團隊的運作。決策同時會伴隨著壓力的產生，不論是處於好的或是壞的壓力，都會影響人在進行決策時的判斷。當處於不適合的高壓力之下，突如其來的決策問題常常會讓人下達不適合的決策，但有時候適當的壓力也會讓人判斷出適合的決策。根據研究發現當一個人在壓力之下，其相對應的認知表現和決策可能會受到不利的影響，特別是在某些條件的壓力之下，此個體可能會1. 屏除外在的刺激(Easterbrook, 1959; Janis & Mann, 1977; Staw, Sandelands & Dutton, 1981)，2. 藉由啟發式法則(也就是經驗法則)進行決策(Shaham, Singer, & Schaeffer, 1992; Klein, 1996)，3. 遭遇到表現的剛性或是狹隘的思想(Friedman and Mann, 1993; Keinan, 1987)，4. 失去個人分析複雜情況和處理訊息的能力(Larsen, 2001)。也有研究發現，在壓力之下任務完成的時間有可能會增加且完成的準確性則會降低(Idzikowski & Baddeley, 1983; McLeod, 1977)。

壓力除了對個體的影響外，也被證明會對團隊的運作造成負面的影響。當在壓力之下，個體可能會去失去自我掌控權並且讓權力更集中於階層的最上級，而且有效的溝通也將會減少(Driskell, Carson & Moskal, 1988)。壓力也可以引出群體思維(也就是群體中的成員會將會忽略掉對他們自我重要的訊息)強制所有的成員堅持一致的決策甚至是錯誤的決策，並且合理化不好的決策(Janis & Mann, 1977)。在人類的生活之中，為了適應環境所帶來的變化或是做出事件的決策，對動作進行抑制控制(inhibitory control)顯得非常重要，許多決策判斷都不是經常性的發生，面臨在短時間狀況下的壓力，將會影響人在進行策判斷\抑制控制的能力。在軍事作戰中，壓力、決策判斷\抑制控制是息息相關的，因為軍事作戰中，常常在關鍵事件發生後，必須要做出正確的決定，決策判斷卻會被壓力所影響，往往可能由於一瞬間的誤判，造成無法挽回的結果。例如:當有歹徒出現在面前時，是必須要馬上做出開槍反應，但是若是歹徒手邊握有人質時，開槍的動作就必須馬上停止，此就是所謂抑制控制。然而，若我們在此事件當中加入需要限制反應時間，無形中加入壓力的心理因素，那麼對於此事件反應中，是否可以適時的作出對的決策呢?

當人類執行決策判斷時，大腦的神經細胞會有同步(synchronization)活化的現象，此現象反映在腦波上會產生某頻帶腦波能量增強的結果，此外隨決策判斷反應時間的縮短，腦波的主要活化區域有逐漸提高的趨勢。因此，藉由腦波訊號的量測與擷取，經由訊號分析後可觀察腦波能量上的改變，便可評判決策判斷能力。在決策判斷/抑制控制研究中，發現在面臨短時間狀況下的壓力是影響決策判斷的一大因素。針對壓力的心理狀況，除了一般實驗中所設計的心理量表外，目前已有針對腦波與心電(ECG)訊號的方式來研究壓力等議題，就心電訊號心率變異（heart rate variability, HRV）的基本概念是認為人體的壓力主要有兩個部份，一個是生理的壓力，一個是心理的壓力；這兩種壓力是否處於放鬆且協調的狀態，可以從心跳速率與呼吸頻率窺知一二。就腦波而言，壓力和腦部前額(prefrontal)區的腦波(特別是α波)有很高的相關性，正向(positive)情緒(例如，喜悅、高興、有興趣)涉及大腦左前額的活耀，負向(negative)情緒(例如，恐懼、悲傷、厭惡)和右前額活耀有關。即便在「靜止(resting state)狀態」下(亦即，受試者不做任何作業或思考)，這種「前額α腦波不對稱性」仍然明顯存在(Davidson, 2000; Fox, 1991)。除了情緒，α腦波的腦前額不對稱性亦可反映出一個人的性格，例如，外向者的左前額腦波比內向者有較強的活躍量，內向、害羞者的右前額腦則有較強的活躍量。

目前對於決策判斷/抑制控制有關的研究，常使用傳統心理學實驗訊號終止任務(stop-signal task)作為典範，然而在傳統訊號終止任務場景中，為避免其他因素干擾，通常利用簡單符號做為刺激(例如：以圈作為反應訊號及以叉作為決策判斷/抑制訊號)，然而在實際生活中卻無法避免這些干擾因素，因此本計畫利用以虛擬場景(射擊訓練)來模擬訊號終止任務，以實際應用於現實生活中，並加入以時間作為壓力來源。此外，目前在神經科學中，常使用腦波與心電訊號技術作為研究方法，目前此技術發展均已臻至成熟，故本計畫將運用交通大學在訊號處理上的優勢，結合腦波與心電訊號技術的優點來探討在壓力生理狀況作業環境下大腦決策判斷與心電訊號的變化。

在此計畫中，先是透過傳統研究型Neuroscan系統來量測的EEG和ECG訊號，並於國防部指定配合單位或是交通大學腦科學研究中心的虛擬動態實驗室進行虛擬場景(射擊訓練)實驗，探討壓力在腦波/心率變異的差異，探討決策表現好和不好之間在腦波EEG與心率變異度上或是決策上的差異，進而建立專屬決策判斷/抑制控制力腦波與心電模組(model)，故不論是在訓練和監測決策判斷/抑制控制能力，或是分析壓力指標等，未來都有很多市場應用的空間。在建立為該模組後，可結合交通大學腦中心所開發之具有高便利性與實用性的可攜式無線EEG 腦機/ECG心電介面裝置，將此研發系統運用於空軍飛行員獲陸軍射擊手，可幫助國軍分析受訓人員於空軍戰機模擬器(如M2000或F16或IDF)及陸軍裝甲兵學校戰車訓練模擬器進行國軍合成化戰場環境下，作戰訓練優異人員之身、心狀態，進而分析易失事學員之生、心狀態與作戰反應即時訊號分析，深入瞭解作戰成敗之生理狀況，以精進整體合成化戰場環境訓練成效。

In military operations, decision-making suppression is an important ability. An accurate decision can bring extremely positive reward and accomplishment, but a wrong decision can cause serious and irreversible result. Therefore, every decision relates and affects the individual and group performance. However, decision-making always comes with stress no matter good or bad and then stress will affect decision maker’s judgment. Under inappropriate stress, sudden decision-making situation often causes inappropriate decision, but appropriate stress sometimes makes people to do the appropriate decision. According to previous studies, when a person is under stress, his/her corresponding cognitive performance and decision may suffer the unfavorable influence, especially under some conditional stress, his/her will probably 1) dismiss external stimulation 2) make a decision by heuristic rule (experience rule) 3) encounter rigidity of performance or narrow thinking 4) lose ability of analyzing complex situation and dealing with information. Another studies suggested that people may spend more time on task and the accuracy of task reduced in stress environment.

In military operations, decision-making suppression is an important ability. An accurate decision can bring extremely positive reward and accomplishment, but a wrong decision can cause serious and irreversible result. Therefore, every decision relates and affects the individual and group performance. However, decision-making always comes with stress no matter good or bad and then stress will affect decision maker’s judgment. Under inappropriate stress, sudden decision-making situation often causes inappropriate decision, but appropriate stress sometimes makes people to do the appropriate decision. According to previous studies, when a person is under stress, his/her corresponding cognitive performance and decision may suffer the unfavorable influence, especially under some conditional stress, his/her will probably 1) dismiss external stimulation 2) make a decision by heuristic rule (experience rule) 3) encounter rigidity of performance or narrow thinking 4) lose ability of analyzing complex situation and dealing with information. Another studies suggested that people may spend more time on task and the accuracy of task reduced in stress environment.

When human execute behavioral inhibition, the nerve cells of brain will have the phenomenon of synchronization activation, this phenomenon reveals that the brain activity have some strong brain wave in some frequency band. In addition, main activities of brain regions have gradual increases respond to short reaction time. Therefore, methods for measuring and analyzing the brain activity (EEG) can be adopted to observe the change of brain activity and then judge the ability of inhibitory control. In the studies of inhibitory control, we can find out that the short-term stress is a major factor in inhibitory control. Stress is a kind of mental condition. In addition to psychological scale, EEG and ECG signal can be adopted to investigate stress condition. According to basic concept of HRV, human stress has two main parts. One is physical stress and the other is mental stress. We can test the heart rate and breathing rate to observe whether these two kinds of stress are in relaxed and coordinated status. According to EEG signals, stress relates to the brain activity of prefrontal area. Positive emotion is related to the left-front brain region but negative emotion is related to the activation of right-front brain region. Even subject is at resting state, the asymmetry of alpha in front brain region still exists. In addition to emotion, the asymmetry of alpha in front brain region can reflect one’s personality. For instance, brain activity in an extrovert’s left front brain region has stronger than one of introvert. Introvert’s right front brain region has stronger activity t than one of extrovert.

Current studies often adopted the traditional psychology experiment (stop-signal task) to investigate the judge's inhibitory control and ability. However, in traditional stop-signal task scene, experimenters usually utilize the simple symbol as stimulation to reduce the interference factors. In real life, we can’t avoid these interference factors. Thus, this project adopts counter strike to simulate stop-signal task and executes the practical application in real life. We also add the limitation of reaction time as stress source. In addition, the study of neuroscience field often utilizes EEG technology as research methods and the development of EEG and ECG technology has already been demonstrated. Therefore, this project will use professional specialty of signal processing in NCTU and then combine the advantage of EEG and ECG technology to investigate the changes in brain activity, heart rate variability, decision-making and performance in stress environment.

In this project, first, we adopt traditional Neuroscan system to measure the EEG and ECG signals simultaneously and build up the counter strike experiment in army base/school or BRC lab in NCTU. We investigate the difference between EEG and Heart rate variability (HRV) under stress environment and different decision (accuracy and wrong decision). Second, we build the exclusive judgment and inhibition control model based on EEG and ECG signals. The model can be wildly used for market in the feature no matter which be adopted in judgment training/monitoring or stress analysis, Then, we can combine conveniently and usable wireless EEG BCI and A+Care™ Telecardio© BCI, which are all developed by BRC lab in NCTU, with the exclusive judgment and inhibition control model. Furthermore, we can adopt this BCI to analyze the physiological and psychological conditions of soldier/air service under battlefield which is simulated by air force fighter simulator (M2000 or F16 or IDF) and tank simulator from army armor school. Thus, we can understand the difference in the physiological and psychological conditions between perfect and unqualified soldier/air service. Further, we can understand the physiological and psychological conditions of success or failure and master the training effectiveness in synthesis battlefield environment.