title: Answering six questions in extracting children's mismatch negativity through combining wavelet decomposition and independent component analysis.
abstract: This study combines wavelet decomposition and independent component analysis (ICA) to extract mismatch negativity (MMN) from electroencephalography (EEG) recordings. As MMN is a small event-related potential (ERP), a systematic ICA based approach is designed, exploiting MMN's temporal, frequency and spatial information. Moreover, this study answers which type of EEG recordings is more appropriate for ICA to extract MMN, what kind of the preprocessing is beneficial for ICA decomposition, which algorithm of ICA can be chosen to decompose EEG recordings under the selected type, how to determine the desired independent component extracted by ICA, how to improve the accuracy of the back projection of the selected independent component in the electrode field, and what can be finally obtained with the application of ICA. Results showed that the proposed method extracted MMN with better properties than those estimated by difference wave only using temporal information or ICA only using spatial information. The better properties mean that the deviant with larger magnitude of deviance to repeated stimuli in the oddball paradigm can elicit MMN with larger peak amplitude and shorter latency. As other ERPs also have the similar information exploited here, the proposed method can be used to study other ERPs.
authors.affiliation: Department of Mathematical Information Technology, University of Jyväskylä, 40014 Jyväskylä, Finland.
authors.forename: Fengyu
authors.initials: F
authors.lastname: Cong
authors.forename: Igor
authors.initials: I
authors.lastname: Kalyakin
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Tiina
authors.initials: T
authors.lastname: Huttunen-Scott
authors.forename: Yixiang
authors.initials: Y
authors.lastname: Huang
authors.forename: Heikki
authors.initials: H
authors.lastname: Lyytinen
authors.forename: Tapani
authors.initials: T
authors.lastname: Ristaniemi
keywords: Averaged trace; Event-related potential; Independent component analysis; Mismatch negativity; Projection; Reliability; Support to absence ratio; Wavelet decomposition