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PubMed · 17030012

The t-CWT: a new ERP detection and quantification method based on the continuous wavelet transform and Student's t-statistics.

Vladimir Bostanov·Boris Kotchoubey
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Abstract

OBJECTIVE: This study was aimed at developing a method for extraction and assessment of event-related brain potentials (ERP) from single-trials. This method should be applicable in the assessment of single persons' ERPs and should be able to handle both single ERP components and whole waveforms. METHODS: We adopted a recently developed ERP feature extraction method, the t-CWT, for the purposes of hypothesis testing in the statistical assessment of ERPs. The t-CWT is based on the continuous wavelet transform (CWT) and Student's t-statistics. The method was tested in two ERP paradigms, oddball and semantic priming, by assessing individual-participant data on a single-trial basis, and testing the significance of selected ERP components, P300 and N400, as well as of whole ERP waveforms. The t-CWT was also compared to other univariate and multivariate ERP assessment methods: peak picking, area computation, discrete wavelet transform (DWT) and principal component analysis (PCA). RESULTS: The t-CWT produced better results than all of the other assessment methods it was compared with. CONCLUSIONS: The t-CWT can be used as a reliable and powerful method for ERP-component detection and testing of statistical hypotheses concerning both single ERP components and whole waveforms extracted from either single persons' or group data. SIGNIFICANCE: The t-CWT is the first such method based explicitly on the criteria of maximal statistical difference between two average ERPs in the time-frequency domain and is particularly suitable for ERP assessment of individual data (e.g. in clinical settings), but also for the investigation of small and/or novel ERP effects from group data.

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Acoustic StimulationAdultAlgorithmsBrainElectroencephalographyEvent-Related Potentials, P300FemaleHumansMaleSignal Processing, Computer-AssistedTime FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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Vladimir Bostanov, Boris Kotchoubey. 2006-10-06. The t-CWT: a new ERP detection and quantification method based on the continuous wavelet transform and Student's t-statistics.. https://doi.org/10.1016/j.clinph.2006.08.012

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