Influence of Binaural Beats on EEG Signal

Abstract

Binaural beats are subjective hearing sensations, which occur when one of tone signals is applied to one ear, and the other one, with a slightly different frequency is applied to the second ear. A listener then receives a resultant sound with an amplitude which changes with a frequency equal to the difference of frequency of applied signals. The aim of this thesis was to examine the influence of binaural beats on changes in the morphology of the brain bioelectrical signal. Verification of previous studies, such as stimulation of binaural beats affects the brain and can cause changes in other frequency bands. Previous studies have been conducted on individual leads and dealt with the occurrence of follow up effect. In the research there were used binaural beats with a frequency of f = 10 Hz. The left ear was exposed to a signal with a frequency of 100 Hz, and the right ear -to a signal with a frequency of 110 Hz, the acoustic pressure level SPL = 73 dB. The research was conducted on a sample group of 20 people. The analysis of average amplitudes of spectral density function of EEG strength signal proved that the exposition of binaural beats brought about a follow-up effect, which means that a component frequency in the EEG signal morphology was observed which corresponds with a frequency of the exposed binaural beats. It was also noted that during the exposition of binaural beats, there occurs a statistically significant decrease of average amplitudes of spectral density function of EEG strength signal for alpha and beta frequency ranges. However, it was observed that the amplitude of spectral density function of the strength has increased in theta frequency range.

Effect of Binaural Stimulation on Attention and EEG

“…The binaural tones show how neuronal firing in the auditory nerve maintains the phase information of the received signal (Kasprzak, 2011;Ozimek et al, 2008). The route of the auditory nerve to the brain allows the exchange of information coming from both sides, before the sound reaches the cortex, ensuring conscious listening.…”

“…This exchange occurs at least in two areas of the auditory nerve: in the upper olive grove body, small mass of gray matter located in the ventral pontine reticular system (in charge of contralateral integration of auditory system), and transfers it to other area, the inferior colliculus (Schwarz, Taylor, 2005). The two signals arriving from different ears are connected in the brain, resulting in a third signal called the binaural tone (Kasprzak, 2011;Padmanabhan et al, 2005).…”

“…Kasprzak examined experimentally the effect of a binaural wave in 20 subjects (Kasprzak, 2011). The carrier frequency was 100 Hz, 73 dB SPL, with 20 minutes of binaural stimulation.…”

The Effect of the Narrow-Band Noise in the Range 4-8 Hz on the Alpha Waves in the EEG Signal

“…The initial 5 min was recorded without the infrasound exposure, 20 min with the signal exposure, and 10 min without the exposure [10]. The study was conducted with the approval of the Local Commission of Bioethics in ód».…”

Influence of Infrasound on the Alpha Rhythm of EEG Signal

“…The initial 5 min was without the infrasound exposition, 20 min with the signal exposition and 10 min without the exposition [7,8].…”