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Frequency-response-based Wavelet Decomposition for Extracting Children’s Mismatch Negativity Elicited by Uninterrupted Sound Department of Mathematical Information Technology ,University of Jyväskylä,Jyväskylä 40014,Finland Center for Intelligent Maintenance Systems,University of Cincinnati,OH 45221,USA School of Psychology, Beijing Normal University,Beijing 100875,China Department of Psychology,University of Jyväskylä, Jyväskylä 40014,Finland Received 6 Apr 2011; Accepted 14 Sep 2011; doi: 10.5405/jmbe.908 Chairman:Hung-Chi Yang Presenter: Yu-Kai Wang Advisor: Dr. Yeou-Jiunn Chen Date: 2013.3.6 Outline Introduction Purposes Materials and Methods Results Conclusions Introduction Other types of activity that overlap MMN are not separated in the time and/or frequency domain To obtain pure MMN activity, researchers have used many signal processing techniques Digital filters Wavelet decomposition (WLD) Principal component analysis(PCA) Independent component analysis(ICA) Introduction Wavelet Decomposition(WLD) Which was especially designed for non-stationary signals First factorizes the signal into several levels with a particular wavelet The coefficients of some of the levels are chosen to reconstruct the desired signal Can thus be regarded as a special band-pass filter Purposes Designs a paradigm based on the fact that The magnitude of the frequency response of WLD and the spectral properties of MMN conform to each other To determine the type of wavelet The number of levels the signal should be decomposed into The levels required for the reconstruction EEG recordings before WLD is performed 2-8.5 Hz was found to be the most Optimal frequency band for MMN in their dataset