• Home > Journal Search > Past Issues

Past Issues

Endnote RefWorks Scholar's Aid Excel TXT
Vol.17, No.2, 91 ~ 101, 2014
Title
The effects of the methods of eye gaze and visual angles on accuracy of P300 speller
 
Abstract
This study was to examine how visual angle of matrix corresponding to the physical properties of P300 speller and eye gaze corresponding to the user`s personal characteristics influence on the accuracy of P300. Visual angle of the matrix was operated as the distance between the user and the matrix and three groups were composed: 60 cm group, 100 cm groups, and 150 cm group. Eye gaze methods was consisted three conditions. Head moving condition was putting eye gaze using head, pupil moving condition was moving pupil with the head fixed, while the eye fixed condition is to fix the eye gaze at the center of the matrix. The results showed that there was significant difference in the accuracy of P300 speller according to the eye gaze method. The accuracy of the head moving condition was higher than the accuracy of pupil moving conditions, accuracy of pupil moving conditions was higher than the accuracy of the eye fixed conditions. However, the effect of visual angle of matrix and interaction effect were not significant. When P300 amplitude of target character was measured depending on how you stare at the target character, P300 amplitude of the head moving condition was greater than P300 amplitude of the pupil moving condition. There was no significant difference in the error distribution in head moving condition and pupil moving condition, while there was a significant difference between two eye gaze conditions and fixed gaze condition. The error was located at the neighboring characters of the target character in head moving condition and pupil moving condition, while the error was relatively distributed widely in fixed eye condition, error was occurred with high rate in characters far away from the center of matrix
Key Words
뇌-컴퓨터 인터페이스, P300 문자입력기, ERP, 시선, 시각도, brain-computer interface, P300 speller, ERP, eye gaze, visual angle
| PDF

로고이미지