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PubMed · 9309607

Generic brain activation mapping in functional magnetic resonance imaging: a nonparametric approach.

M J Brammer·E T Bullmore·A Simmons·S C Williams·P M Grasby·R J Howard·P W Woodruff·S Rabe-Hesketh
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Abstract

We report a novel method to identify brain regions generically activated by periodic experimental design in functional magnetic resonance imaging data. This involves: 1) registering each of N individual functional magnetic resonance imaging datasets in a standard space; 2) computing the median standardised power of response to the experimental design; 3) testing median standardised power at each voxel against its nonparametrically ascertained distribution under the null hypothesis of no experimental effect; and 4) constructing a generic brain activation map. The method is validated by analysis of 6 null images, acquired under conditions when the null hypothesis was known to be true; 8 images acquired during periodic auditory-verbal stimulation; and 6 images acquired during periodic performance of a covert verbal fluency task.

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Acoustic StimulationAuditory CortexBrainBrain MappingHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingSignal Processing, Computer-AssistedJournal ArticleResearch Support, Non-U.S. Gov't

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M J Brammer, E T Bullmore, A Simmons, S C Williams, P M Grasby, R J Howard, P W Woodruff, S Rabe-Hesketh. 1997. Generic brain activation mapping in functional magnetic resonance imaging: a nonparametric approach.. https://doi.org/10.1016/s0730-725x(97)00135-5

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