Brainwaves Analysis Using Spectral Entropy in Children with Autism Spectrum Disorders (ASD)

In the beginning of this recent years, the number of children with Autism Spectrum Disorders (ASD) in Indonesia has increased. Previous studies showed that brain activity of children with ASD was found to be prominently different in frontal and temporal lobes. One of the known methods to measure brain activity in both normal and disorder brain condition is the measurement of brainwaves using electroencephalography (EEG). Therefore, this study aimed to analyze the brainwaves of frontal and temporal lobes of children with ASD, using a calculation of spectral entropy. The subjects group on this research were the children with ASD and the normal children as a control group. EEG recordings were conducted while the children from both of the group was resting and eyes closed. As a preprocessing method, data filtering and algorithm normalization were done to get EEG data. Periodogram Welch method, based on Fast Fourier Transform (FFT), was then used to calculate the power spectral entropy (PSE) of alpha and beta frequency bands. The results were show that at 14 second of children with ASD had the PSE peak. The peak that was observed in the The frontal lobe (F8) located in the right hemisphere was higher than the peak shown in the temporal lobe (T8). However, the peak of left hemisphere T7 was higher than F7.On the control object, T8 had a peak with values that was greater than the peak of F8 located in the right hemisphere. Meanwhile, for the left hemisphere, the peak of F7 was greater than T7. Based on these results, it could be concluded that the ASD object and the control object had different frontal and temporal lobe PSE conditions.