Analyses of EEG background activity in Autism disorders with fast Fourier transform and short time Fourier measure

Electroencephalography (EEG) is widely used in clinical settings to investigate neurophysiology. Since EEG signals contain a wealth of information about brain functions, there are many approaches in analyzing EEG signals with spectral techniques. In this study we have investigated the EEG background activity in Autism disorder using a number of frequency analysis techniques. We have used fast Fourier transform (FFT), short time Fourier transform (STFT) and STFT at bandwidth of total spectrum (we named its STFT-BW) for 19 channel is of EEG. Coefficients of the EEG in 10 Autism disorders and 7 age matched control subjects were measured. These coefficients were assessed with variance analysis. We find no significant different between Autism disorders and control subjects EEGs with STFT. On the other hand, Autism disorders had significantly difference FFT value (p<0.01) at electrodes FP1 and F3. STFT at bandwidth (STFT-BW) had excellent different. FP1, F3 and T5 with (p<0.01) and F7, T3 and O1 with (p<0.05) had significantly differences. In addition our findings suggested that STFT-BW have 82.4% discriminate between normal and Autism subjects with Mahalanobis distance but FFT and STFT havenpsilat results significant.