Simultaneous FMRI/CBV and EEG During Spike-Wave Seizures in WAG/Rij Rats

In absence and other generalized seizure disorders, an abnormal electrical activity termed as spike-wave discharges (SWD) is observed by EEG. fMRI during SWD in humans and animal absence epilepsy models show both increases and decreases in BOLD signals. Here we show regional BOLD increases/decreases during SWD accompanied by CBV increases/decreases in nearly the same areas for anesthetized WAG/Rij rats. Further work will be needed to determine if regions of BOLD decreases during SWD represent vascular steal, a primary neuronal mechanism, or a defect in neurovascular coupling. These findings will be important for the interpretation of various fMRI signals in human absence epilepsy