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Hello - are you really sure you want to contrast event-related BOLD response against block-design response? It doesn't necessarily mean very much, as you can't assume that the neurovascular coupling is comparable in the two cases…..? Cheers, Steve. On 24 Nov 2012, at 18:01, Jennifer Townsend wrote: > I am trying to compare activation from an event-related version of a paradigm to a block version. Our subjects have 1 run of the block and 3 runs of the ER. I have 1st level analyses for each of these 4 runs per subject and am now wondering which is the correct way is to setup the higher-level Block vs ER analysis: > > 1.) Do I first create a 2nd level ER analysis for each subject (with the 3 runs as the input) and then set up a 3rd level analysis with the copes from the block 1st level and the ER 2nd level (so 2 copes per subject) and run a paired t-test? > > or > > 2) Do I create a 2nd level analysis with 4 inputs per subject (1 block FEAT and 3 ER FEATs) and then set up the paired t-test with contrast weights 1 (block) and .33 (for each of the 3 ERs)? > > Many thanks, > Jen > --------------------------------------------------------------------------- Stephen M. Smith, Professor of Biomedical Engineering Associate Director, Oxford University FMRIB Centre FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK +44 (0) 1865 222726 (fax 222717) [log in to unmask] http://www.fmrib.ox.ac.uk/~steve ---------------------------------------------------------------------------