Detection of the brain response during a cognitive task using perfusion-based event-related functional MRI

Event-related (ER) fMRI has evoked great interest due to the ability to dep ict the dynamic features of human brain function during various cognitive t asks. Thus far, all cognitive ER-fMRI studies have been based on blood oxyg enation level-dependent (BOLD) contrast techniques. Compared with BOLD-base d fMRI techniques, perfusion-based fMRI is able to localize the region of n euronal activity more accurately. This report demonstrates, for the first t ime, the detection of the brain response to a cognitive task using high tem poral resolution perfusion-based ER-fMRI. An English verb generation task w as used in this study. Results show that perfusion-based ER-fMRI accurately depicts the activation in Broca's area. Average changes in regional relati ve cerebral blood flow reached a maximum value of 30.7% at similar to 6.5 s after the start of stimulation and returned to 10% of the maximum value at similar to 12.8 s, Our results show that perfusion-based ER-fMRI is a usef ul tool for cognitive neuroscience studies, providing comparable temporal r esolution and better localization of brain function than BOLD ER-fMRI. Neur oReport 11:2533-2536 (C) 2000 Lippincott Williams & Wilkins.