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Instead of calculating the average you should calculate the min of the two conditions (con1,con2), this is the basis of the conjunction analysis. Michael Am 10.08.2016 um 04:06 schrieb MCLAREN, Donald: > Marek, > > What the reviewer is asking for is not possible because the conjunction > does not produce a con_ image. Without the con_ image, you can't do the > second-level analysis. > > I think what the reviewer is asking for is to create a contrast of the > average of the two conditions and to test if the average of the two > conditions is different between the groups. > > Best Regards, > Donald McLaren, PhD > > > On Wed, Aug 3, 2016 at 8:35 AM, Marek Wypych <[log in to unmask] > <mailto:[log in to unmask]>> wrote: > > Dear SPMers,____ > > We performed an experiment on readers and pre-readers with speech > and print conditions. On second level analysis we computed null > conjunction for the 2 contrast in each group (one sample t-test) > which produced significant activation in readers while not in > pre-readers. However, when the paper was sent to review one of the > reviewers wanted us “to compute the conjunction of print and speech > on the first level and put these contrasts into a 2-sample t-test on > the second-level”.____ > > However we came across some difficulties. If we save thresholded SPM > map from each subject when performing null conjunction in SPM > contrast manager and feed these maps to 2^nd level the model cannot > be estimated and there is an error saying “there are no inmask > voxels” (even though we used very lenient p<0.05 uncorrected > threshold for the 1st level conjunction). Is there a better way of > doing multisubject conjunction?____ > > Thank you in advance,____ > > Marek > > > > > -- > Marek Wypych PhD > Laboratory of Brain Imaging (LOBI) > Neurobiology Center > Nencki Institute of Experimental Biology > Pasteur 3, 02-093 Warsaw, Poland > Tel.: +48 22 5892 550 > http://lobi.nencki.gov.pl/ > > -- <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Dr. Michael Erb Department of Biomedical Magnetic Resonance University of Tübingen Hoppe-Seyler-Str. 3 72076 Tübingen, Germany Tel.: +49(0)7071/2987753 priv. +49(0)7071/61559 Fax.: +49(0)7071/294371 e-mail: <[log in to unmask]> www: http://www.medizin.uni-tuebingen.de/Forschung/Kliniken/Radiologie/Biomedizinische+Magnetresonanz.html <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<