Visualization of Epilepsy Patient’s Brain Condition based on Spectral Analysis of EEG Signals using Topographic Mapping

In analyzing the epilepsy patient data it is necessary for a doctor to know where the epileptic focus are located. This information is related to the determination of the type of drug delivery and the therapeutic measures that will be performed for the epilepsy patient. In this research, a system that can visualize the state of the brains of epilepsy patients by performing an analysis of brain wave signals or electroencephalography (EEG) is built. Visualization is performed using topographic mapping techniques on each EEG signal sub-band, namely delta, theta, alpha, beta and gamma sub-bands. The feature extraction process is conducted using Fast Fourier Transform (FFT) to transform signals from time domain into frequency domain. The absolute power and relative power data of EEG signals are used as input values in the visualization process. The results are compared to neurologist analysis and they indicate that this system can visualize the brain condition of epileptic patients to find out where the epileptogenic zone is located by adjusting data cutting process to the duration of the seizure wave that occurs.