BRAIN POTENTIALS ASSOCIATED WITH EYE FIXATIONS DURING VISUAL TASKS UNDER DIFFERENT LIGHTING SYSTEMS

The variations of eye fixation related potentials (EFRPs) were examine d in hvo tasks under three lighting conditions for assessment of light ing environments. Sixteen subjects participated in two tasks: a diffic ult and an easy reading task under three lighting conditions: Spot lig ht (S), General light (G) and Mixed light (M). EEG (Oz) and EOG were r ecorded. EEG epochs time-locked to onset of eye fixations were collect ed at random and averaged separately in two arrays to obtain a pair of EFRPs. Two wave forms under the S were similar, although those under the G showed the disparity, the largest disparity being in the easy ta sk under the G. Under the S, wave forms of EFRPs were stable in the di fficult task. The amplitude changed with the task load. The results su ggested that EFRPs might be an index of the work load under lighting c onditions.