title: Decoding Dynamic Brain Patterns from Evoked Responses: A Tutorial on Multivariate Pattern Analysis Applied to Time Series Neuroimaging Data.
abstract: Multivariate pattern analysis (MVPA) or brain decoding methods have become standard practice in analyzing fMRI data. Although decoding methods have been extensively applied in brain-computer interfaces, these methods have only recently been applied to time series neuroimaging data such as MEG and EEG to address experimental questions in cognitive neuroscience. In a tutorial style review, we describe a broad set of options to inform future time series decoding studies from a cognitive neuroscience perspective. Using example MEG data, we illustrate the effects that different options in the decoding analysis pipeline can have on experimental results where the aim is to "decode" different perceptual stimuli or cognitive states over time from dynamic brain activation patterns. We show that decisions made at both preprocessing (e.g., dimensionality reduction, subsampling, trial averaging) and decoding (e.g., classifier selection, cross-validation design) stages of the analysis can significantly affect the results. In addition to standard decoding, we describe extensions to MVPA for time-varying neuroimaging data including representational similarity analysis, temporal generalization, and the interpretation of classifier weight maps. Finally, we outline important caveats in the design and interpretation of time series decoding experiments.
authors: Macquarie University, Sydney, Australia.|ARC Centre of Excellence in Cognition and its Disorders.|University of Sydney.
authors: Tijl
authors: T
authors: Grootswagers
authors: Macquarie University, Sydney, Australia.|ARC Centre of Excellence in Cognition and its Disorders.
authors: Susan G
authors: SG
authors: Wardle
authors: ARC Centre of Excellence in Cognition and its Disorders.|University of Sydney.
authors: Thomas A
authors: TA
authors: Carlson
mesh_terms: D001921:Brain / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D059907:Functional Neuroimaging / Q000379:methods*; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods*; D015999:Multivariate Analysis; D012815:Signal Processing, Computer-Assisted