Electrooculogram based study to assess the effects of prolonged eye fixation on autonomic responses and its possible implication in man-machine interface

Need of an alternative method for communication has been seriously felt for man-machine interface (MMI) because of difficulties in the analysis of complex electroencephalogram (EEG). The proposed method analyses the alterations in autonomic responses due to prolonged eye gaze. The experimental paradigm was designed to include 20 trials of 30 s for eye gaze and 10 s for relaxation. Along with electrooculogram (EOG), electrocardiogram (ECG), pulse plethysmogram (PPG) and electrodermal activity (EDA) was recorded from the five male subjects. Results demonstrated that the eye gaze modulates heart rate, pulse rate and EDA signals that were too analyzed to occur with the latency of nearly 5 s, which is nearer to the EEG based brain-machine interfaces (BMI). The alterations in autonomic variables persist for longer duration and the maximum change in pulse rate was observed at 26.79 s (5.16 beats/minute) in comparison to the maximum change of heart rate (6.27 beats/minute) at 27.45 s, respectively. Further, the changes in EDA were found more at the onset of events. With the above findings, it can be suggested that the changes in autonomic responses with the mental effort produced by eye gaze were distinct and provides a good platform for the development of MMI.