A confrontational naming task produces congruent increases and decreases in PET and fMRI

This work uses the well-established (by PET) confrontation naming task to c ompare PET and fMRI in a cognitive activation experiment. The signal change s from this task are much less than the changes caused by visual or motor a ctivation tasks used in previous comparisons. ANOVA methods adjusted for mu ltiple comparisons were used to determine significant changes in signal bet ween confrontation naming and figure size discrimination tasks. All 17 sign ificantly increased regions (confrontation naming signal greater) seen on o ne modality were increased on bath modalities. Ten of 13 regions that were significantly decreased on one modality were decreased on the other. Three mismatched regions showed a significant decrease on one modality and a nons ignificant increase on the other. This study could not detect a consistent difference in activation site location between PET and fMRI. (C) 1999 Acade mic Press.