Effects of Light-Emitting Diode Light on Human Electroencephalogram in Comparison with Fluorescent Light

Abstract

Selecting suitable illumination is an integral part of increasing productivity in the office or factory, because poor lighting conditions may often cause decreased work efficiency. Light emitting diode (LED) light is becoming recognized as one of the most promising general sources of illumination. We conducted spectral power analysis of electroencephalograms (EEGs) obtained during resting and cognitive task activities to identify the effects on human arousal and cognitive performance under LED light compared with conventional fluorescent light. Methods: Thirteen healthy, right-handed students participated in the present study. Each subject took part in two experimental sessions, one under fluorescent and one under LED lighting conditions. The experimental measurements consisted of a resting state EEG, an event-related potential (ERP) during a visual working memory (VWM) task, and a questionnaire about subjective feelings regarding the lighting conditions. The EEG power spectra, the amplitude and latency of the P300 ERP component, the behavioral responses for the VWM task, and the questionnaire data were compared for the two lighting conditions. Results: The EEG spectral power showed no difference between the LED and fluorescent lighting conditions. The amplitude of the P300 component decreased significantly with increasing numbers of items, while there were no differences between the two lighting conditions. Additionally, behavioral responses and subjective feelings were the same under the two lighting conditions. Conclusions: Our study suggests that there are no significant differences between LED light and fluorescent light on the human arousal state and VWM.