Abstract:
The EEG has become one of the most important diagnostic tools in clinical neurophysiology. However, EEG analysis still relied mostly on its visual inspection. Due to the fact that visual inspection is hardly allow any statistical analysis or standardization, several methods were proposed in order to quantify the information of EEG. Among these methods, the Fourier Transform emerged as a very powerful tool capable of characterizing the frequency components of EEG signals. Fourier Transform has some disadvantages that limit its applicability and therefore, other methods for extracting hidden information from EEG are necessary. The objective of this research is to develop off-line monitoring software for comparing methods of EEG signal analysis, Fast Fourier Transform, Short Time Fourier Transform (Gabor Transform) and B-Spline Wavelet Transform. The results form these analysis methods will be presented as 2D and 3D brain mapping and will be computed to detect EEG spike. The software was developed using Microsoft Visual Studio 2003, C#.Net and DirectX9.0C.
Finally, the software can enable users to scan and detect spikes, display spectrums on 3D scalp model and also allow users to play and study the hidden information from all provided time-frequency analysis methods. The result Time frequency resolution achieved with Wavelet Transform allowed a very detailed study of the time evolution of the frequency peaks during the seizure. This result is in agreement with the described with Gabor Transform.""