Dear Spmers,
We performed an event related fMRI experiment on 12 subjects.
We had 3 conditions : A, B and N (for a null event).
In a first step, we performed a SPM analysis for each individual
case1 : for A condition vs B condition (contrast 1 -1)
case 2 : for B condition vs A condition (contrast -1 1)
In a second step we performed a second level analysis (random effect)
using at input the 24 .con files previously obtained, a two T-tail test
as basic model and two contrast (ie 1 -1 and -1 1).
Questions :
1) Is our analysis correct in order to access which areas are activated
by A vs B condition or B vs A condition ?
2) what will be the difference if we used a one T-tail test as basic
model on the 12 .con files obtained for case 1 or case 2 ?
Many Thanks
Michel Dojat
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Michel Dojat
Unité mixte INSERM-UJF U438 "RMN Bioclinique"
CHU de Grenoble - Pavillon B
BP 217
38043 Grenoble Cedex 9
Phone: 33 4 76 76 57 48 (secr.) / 33 4 76 76 88 97 (direct)
Fax: 33 4 76 76 58 96
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http://rhea.ujf-grenoble.fr/people/mdojat
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