2:45 PM - 3:00 PM
[HTT21-05] On the Method to Evaluate Environmental Sound Using EEG Analysis
Keywords:The environment, Sound, EEG
1.Introduction
The outbreak of the "Covid-19" has prevented us from going out. Such rapid changes in the living environment have greatly impaired the quality of daily life. Therefore, from the perspective of creating a comfortable space, it is necessary to regain a part of people's lives so far.
2.Purpose and method of research
In the future, we may not be able to go out and go to our favorite places. Therefore, if we can experience something that reminds us of the target environment by using the idea of remoteization that has become a corona disaster, we think that it is important to experience a comfortable environment in a pseudo manner. In this research, we focused on sound. We aim to clarify the existence of a sound environment that the person feels comfortable without being aware of it, and the tendency of that sound. We let the subjects listen to endless recordings of the original sound in each environment. To identify the classification of environmental sounds that tend to be preferred by the subjects and their individual differences, the α-wave frequency band of the brain wave, which is a physiological response, was compared and analyzed.
3.EEG measurement
The equipment used in the experiment was a PCM recorder, EMOTIV EPOC X, and a monitor earphone. With the dedicated software EMOTIV PRO, we analyzed only the ease of occurrence of the α wave frequency band and the numerical values from the brain waves measured for each environment. The experiment was conducted for students without telling the contents of the experiment. All with slight differences detected similar waveforms. It was possible to classify into pattern 1 (large brain wave intensity) and pattern 2 (low brain wave intensity) from the appearance of the intensity of the α wave average value for each section. From the measurement results, the tendency of the preferred environmental sound differs depending on the pattern. From the above, it is considered that there is a relationship between the ease of occurrence of the α wave frequency band and the characteristics of the preferred environment, although there are some individual differences among listeners.
4.Fourier Analysis
In order to compare the tendency of the appearance of the α wave intensity value of the environmental sound itself for each pattern, a Fourier Analysis was performed using the data obtained from the EEG measurement experiment. The waveform of the approximate curve for both patterns has a similar shape. The comparison of the tendency to increase or decrease the amplitude at different frequencies resulted in three different combinations. Although there are few elements in common with each sound type, it can be said that the perspective is similar as an environmental sound. In addition, a large difference in the amplitude of each environmental sound was observed only in the small frequency band of pattern 1. It is probable that they were sensitive to each sound in the section and were deeply immersed in the sound source in a relaxed state in a short time.
5.Conclusion
In this study, we conducted EEG measurement experiments and compared the intensities of the α wave frequency band. By performing a Fourier Analysis, the appearance of the α wave frequency band was analyzed. As a result, those who can hear the sound source deeply prefer calm environmental sounds, and those who cannot hear it tend to prefer "mixed sounds", which are difficult to hear individually. We think there may be. However, it was not possible to find a clear degree of comfort in the environmental sound itself. It is thought that the reason is that the visual image was difficult to spring up because the measurement time of the experiment was short. Individual differences must be considered to evaluate environmental sounds in detail. Therefore, it is necessary to perform verification with other factors and handle more data statistically.
The outbreak of the "Covid-19" has prevented us from going out. Such rapid changes in the living environment have greatly impaired the quality of daily life. Therefore, from the perspective of creating a comfortable space, it is necessary to regain a part of people's lives so far.
2.Purpose and method of research
In the future, we may not be able to go out and go to our favorite places. Therefore, if we can experience something that reminds us of the target environment by using the idea of remoteization that has become a corona disaster, we think that it is important to experience a comfortable environment in a pseudo manner. In this research, we focused on sound. We aim to clarify the existence of a sound environment that the person feels comfortable without being aware of it, and the tendency of that sound. We let the subjects listen to endless recordings of the original sound in each environment. To identify the classification of environmental sounds that tend to be preferred by the subjects and their individual differences, the α-wave frequency band of the brain wave, which is a physiological response, was compared and analyzed.
3.EEG measurement
The equipment used in the experiment was a PCM recorder, EMOTIV EPOC X, and a monitor earphone. With the dedicated software EMOTIV PRO, we analyzed only the ease of occurrence of the α wave frequency band and the numerical values from the brain waves measured for each environment. The experiment was conducted for students without telling the contents of the experiment. All with slight differences detected similar waveforms. It was possible to classify into pattern 1 (large brain wave intensity) and pattern 2 (low brain wave intensity) from the appearance of the intensity of the α wave average value for each section. From the measurement results, the tendency of the preferred environmental sound differs depending on the pattern. From the above, it is considered that there is a relationship between the ease of occurrence of the α wave frequency band and the characteristics of the preferred environment, although there are some individual differences among listeners.
4.Fourier Analysis
In order to compare the tendency of the appearance of the α wave intensity value of the environmental sound itself for each pattern, a Fourier Analysis was performed using the data obtained from the EEG measurement experiment. The waveform of the approximate curve for both patterns has a similar shape. The comparison of the tendency to increase or decrease the amplitude at different frequencies resulted in three different combinations. Although there are few elements in common with each sound type, it can be said that the perspective is similar as an environmental sound. In addition, a large difference in the amplitude of each environmental sound was observed only in the small frequency band of pattern 1. It is probable that they were sensitive to each sound in the section and were deeply immersed in the sound source in a relaxed state in a short time.
5.Conclusion
In this study, we conducted EEG measurement experiments and compared the intensities of the α wave frequency band. By performing a Fourier Analysis, the appearance of the α wave frequency band was analyzed. As a result, those who can hear the sound source deeply prefer calm environmental sounds, and those who cannot hear it tend to prefer "mixed sounds", which are difficult to hear individually. We think there may be. However, it was not possible to find a clear degree of comfort in the environmental sound itself. It is thought that the reason is that the visual image was difficult to spring up because the measurement time of the experiment was short. Individual differences must be considered to evaluate environmental sounds in detail. Therefore, it is necessary to perform verification with other factors and handle more data statistically.