Siska Ayu Nirmala, MS Thesis, Dept. of Physics, Bandung Institute of Technology, 2015
The human brain is an organ that regulates and coordinates all activities of the body. Neuroimaging is a way to study how the brain works. One of the latest neuroimaging instrumentation that is non-invasive and being developed is Brain ECVT. In this study, 2-electrode Brain ECVT was used in two experiments. In the first experiment, Brain ECVT was used to record the capacitance data for various type of ionic solutions Na+, K+, Ca2+, and Cl-, as embodied in the neurons, with different molarity level. The molarity used are 10 mM, 50 mM, 150 mM, 300 mM, and 400 mM. The experimental results indicate that the increased molarity of the solution causes the decrease in capacitance value. In the second experiment, 2-electrode Brain ECVT was used to record the activity of the human brain during stress and relax condition . Stress and relax condition were achieved by Guided
Imagery Technique. The experiment involved five participants for 6 minutes for each condition. 2-electrode Brain ECVT signal analyzed by two techniques, the first technique used Wavelet Transformation and Fast Fourier Transform, and the second technique used Periodogram-Welch Method. These both techniques indicate that the value of total power spectral and average power spectral for stress conditions is higher than the relax conditions. The power spectral estimation using Periodogram-Welch showed that alpha wave and beta wave component appear in both conditions, stress and relax.
Keywords: 2-electrode Brain ECVT, Stress, Relax, Wavelet Transformation, FFT, Periodogram-Welch