Department of Biomedical Engineering, Kyung Hee University, Republic of Korea.
Department of Biomedical Engineering, Kyung Hee University, Republic of Korea.
Comput Biol Med. 2014 Feb;45:118-25. doi: 10.1016/j.compbiomed.2013.12.001. Epub 2013 Dec 17.
P300 is an event related potential of the brain in response to oddball events. Brain Computer Interface (BCI) utilizing P300 is known as a P300 BCI system. A conventional P300 BCI system for character spelling is composed of a paradigm that displays flashing characters and a classification scheme which identifies target characters. To type a word a user has to spell each character of the word: this spelling process is slow and it can take several minutes to type a word. In this study, we propose a new word typing scheme by integrating a word suggestion mechanism with a dictionary search into the conventional P300-based speller. Our new P300-based word typing system consists of an initial character spelling paradigm, a dictionary unit to give suggestions of possible words and the second word selection paradigm to select a word out of the suggestions. Our proposed methodology reduces typing time significantly and makes word typing easy via a P300 BCI system. We have tested our system with ten subjects and our results demonstrate an average word typing time of 1.91 min whereas the conventional took 3.36 min for the same words.
P300 是大脑对异常事件的事件相关电位。利用 P300 的脑机接口 (BCI) 被称为 P300 BCI 系统。传统的字符拼写 P300 BCI 系统由显示闪烁字符的范式和识别目标字符的分类方案组成。要输入一个单词，用户必须拼写单词的每个字符：这个拼写过程很慢，输入一个单词可能需要几分钟的时间。在这项研究中，我们通过将单词建议机制和字典搜索集成到传统的基于 P300 的拼写器中，提出了一种新的单词输入方案。我们的新的基于 P300 的单词输入系统由初始字符拼写范式、提供可能单词建议的字典单元以及用于从建议中选择单词的第二个单词选择范式组成。我们的方法通过 P300 BCI 系统显著减少了输入时间，并使单词输入变得容易。我们已经用十个受试者对我们的系统进行了测试，结果表明，对于相同的单词，我们的系统的平均单词输入时间为 1.91 分钟，而传统的系统则需要 3.36 分钟。
