【作者】 高扬；

【导师】 万柏坤；

【作者基本信息】 天津大学 ， 生物医学工程， 2004， 硕士

【摘要】 脑—机接口（Brain-Computer Interface——BCI）是在人脑和计算机或其他电子设备之间建立的一种直接的信息交流和控制通道, 是一种不依赖于常规大脑输出通路（外周神经和肌肉组织）的全新的信息交流系统。瘫痪病人所患的多种神经肌肉紊乱都会阻断大脑与外界环境的信息交换及对其的控制通道，使患者丧失基本的运动功能和正常的交流能力，严重的已经不能借助传统辅助装置进行基本交流。BCI作为一种全新的信息交换和控制技术，将能为瘫痪病人，特别是那些丧失了基本肢体运动功能但思维正常的患者，提供一种与外界进行信息交流和控制的新途径，正受到越来越多的重视。本文根据90％脑神经功能正常的人在短时间闭眼后脑电（EEG）中alpha（α）波幅均可明显增强这一普适特征，设计了一套简便易行的基于脑电α波的脑—机接口系统。该系统仅需在操作者头后部放两个脑电检测电极，无需训练就可以快速而可靠地控制外接机电装置运行开关，还可以扩展为多选项实时控制系统。作者首先搭建了闭眼alpha波控制系统（Eye-Closure Based Activation System，ECBAS），引入开关抑制模块和声音反馈减少误控制，实现了对单个开关的快速可靠控制，经10名操作者试验，获激活开关平均时间2.4秒、平均错误率3％的好成绩，证实该系统可以简便易行、快速可靠地控制外部机电设备的开关运行。在此基础上，进一步开发设计了基于计算机LabVIEW平台显示的循环灯选择系统（Recycling Lights Choice Menus System, RLCMS），利用α波控制单个开关的功能，通过四灯循环作为指示菜单，实现了四个目标的α波控制选择。为验证系统的有效性，设计了四时程、每时程20次连续选择（时间递减）实验。经5名操作者试验，证实每个受试者均只需少数训练时程即可达到10%或更低的错误率，说明系统无需繁复学习或生物反馈训练的易操作性，以ECBAS为基础的扩展功能可以实现由两种状态选择控制到多个选项的选择控制。最后，再以RLCMS为原型，设计了α波小车控制系统（Minicar System Controlled by Alpha, MSCA）以实现α波对电动小车的实时控制。经5名操作者参加连续25次随机方向控制实验，平均正确率达到91.2％，再次证实本文设计的α波的脑—机接口系统进行多选项控制的可实现性和潜在应用价值。如实现系统集成化和便携化，配置适当的控制显示面板，可望进一步开发出专供那些患有全身性重症瘫痪但头脑功能正常的残疾人使用的新型助残轮椅等产品。更多还原

【Abstract】 Brain Computer Interface (BCI) is a direct information communication and control channel established between human and computer or other electronics devices and it is a wholly new communication system that does not depend on the brain’s normal output pathways of peripheral nerves and muscles. A wide variety of neuromuscular disorders can disrupt the channels through which the brain communicates with and controls its external environment, usually deprive patients of their basic movement function and normal communication. Those most severely affected may be completely locked in to their bodies, unable to communicate with conventional assistive devices. As a wholly new information communication and control technology, EEG-based BCI may provide the paralyzed, especially those “locked-in” but with intact ideation, with an effective communication and control channels with outside world. That’s why BCI is winning more and more attention. In terms of the fact that increase in the alpha component of EEG during eye closure exists among at least 90% of people with normal brain neural function, this dissertation presents a simple and easy alpha wave based BCI system. It requires only two electrodes to be placed towards the rear of the head for each person, can rapidly and highly reliably control a switch needless of training and it can further be extended to offer more sophisticated real time control. First, the lab Eye-Closure Based Activation System (ECBAS) is established. By providing with Switch Suppress Module（SSM）and sound feedback, a user can rapidly and reliably switch a single indicating light. Ten subjects attended ECBAS experiment by switch an indicating light continuously for 50 times. They have acquired the average error rate of 4% and average switch time of 2.4 seconds. This result indicates that the alpha amplitude variety with eye open and eye closure can be a rapid and reliable control for electronics switch. Next, on base of ECBAS, the Recycling Lights Choice Menus System (RLCMS) is developed and designed on the computer LabVIEW platform. It Extends ability of switching a light during eye closure to four options choice by a recycling light choice menu. Five subjects attended the experiment for RLCMS by continuously choosing demanded options for 20 times in four sections. All subjects have <WP=4>acquired an error rate of at least 10% after a short-term training. It is indicated that RLCMS is easy to learn and operate needless of extra biofeedback training and that the ECBAS is reliable enough to be extended to four options control from only two-state switch control. Last, with RLCMS as a prototype, the Minicar System Controlled by Alpha (MSCA) is designed to realize telecontrol minicar control by eye closure alpha wave. Five subjects attended continuous 25 times random command control experiment, and they have acquired average correction rate of 91.2%. By successfully realizing the real time control of outer device, it is proved that the RLCMS is feasible and with potential application value. With further development of integrated and portable system and suitable control panel, this alpha wave based BCI system could provide those locked-in but with intact mind with a new assistive product, such as control of a wheelchair.更多还原