A study of noise effect on the fast brain activity

Abstract

This paper describes the effect of noise on the fast brain activity using Electroencephalogram (EEG). This study aims to find the correlation between noise exposures to the development of stress and investigate either it does affect the fast brain activity of human. There were 13 males aged between 20 to 22 years old with no past medical history voluntary participated in this study. PowerLab 4/25T Data Acquisition Systems (ML865; ADInstruments, Canada) were used to measure EEG signal during the experiment. Subjects were exposed to the noise at 90 dB for ten minutes. Noise at 90 dB was generated by using INTERM M500 Power Amplifier (INTERM M500, Cunnings, UK).This study focused only on two types of brain wave which are alpha (8-12 Hz) and beta wave (13-30 Hz). Alpha wave is important as stress indicator meanwhile beta wave is associated with fast brain activity such as analytical problem solving, judgment, decision making and processing information. EEG signals were recorded while subjects performed IQ test with and without noise exposure. High magnitude of alpha wave and low magnitude of beta wave that obtained before the noise exposure indicates that subjects were relaxed yet focused. However, when subjects exposed to the noise, beta waves magnitude increase, indicates that subjects in alert and agitated. Meanwhile, the decrease of alpha wave magnitude shows that subjects in tense. Wilcoxon test showed a statistically significant differences in mean of alpha and beta wave magnitude while performed IQ test with and without noise exposure (p<0.05).