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Hello all, I have a question regarding some ICA results I received on a series of fMRI images from an epileptic patient who underwent a continuous EEG-fMRI scan. The patient was scanned for interictal epileptiform activity that occurred on her EEG. I performed spatial ICA and found one component that I am convinced is related to the interictal epileptic spikes. The timing of the BOLD response corresponds to that of the epileptic spikes and the activations are occurring in what looks like the temporal lobe (the patient was diagnosed with right temporal lobe epilepsy). However, the activations have a positive z-score but the BOLD response is showing a DECREASE at each of the spike locations in the spatial brain maps (shown by the large signal discharges in the attached images). This is puzzling to me as I am expecting a BOLD signal increase and positive spatial weights. I have attached two .jpg files showing the brain maps of the component. Is it possible that perhaps the BOLD signals are INCREASING because of the sign ambiguity when doing ICA and that the spatial weights should be DEACTIVATIONS with the same z-scores (which means all I have to do is multiply the time course and spatial weights by negative 1)? If not, how is it that I am getting positive spatial weights with a declining BOLD response at each spike? These results are output from the GIFT ICA program. Thank you. Todd Penney