Electroencephalography (EEG) is an essential tool for the evaluation and treatment of neurophysiologic disorders. Careful analysis of the EEG records can provide insight and improved understanding of ...the mechanism causing disorders. In this study we have investigated the EEG background activity in patients with Autism disease using frequency analysis methods. We calculated LZ complexity, Short Time Fourier Transform (STFT) and also STFT at bandwith of total spectrum (we name it STFT BW) for 19 channels of EEG. Coefficients of the EEG in 11 Autism patients and 10 age control subjects with the same age were measured. These coefficient assessments 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 LZ complexity value (p < 0.05) at electrodes F7, T3 and T5. STFT at bandwidth (STFT BW) had excellent different. FP1, F3 and T5 with (p<0.01) and F7, T3 and Ol with (p < 0.05) had significantly differences. In addition our findings suggested that STFT_BW have 81.0% discriminate between normal and Autism subjects with Mahalanobis distance but LZ complexity and STFT haven't results significant.
