Abstract #0376

Kim T, Hendrich K, Kim S

Changes in arterial cerebral blood volume (&[Delta]CBVa) during stimulation were quantified by modulation of tissue and vessel (MOTIVE) signals with arterial spin labeling, and then compared with changes in total cerebral blood volume (&[Delta]CBVt) determined by injection of contrast agent. There are no significant differences between &[Delta]CBVa and &[Delta]CBVt. These results demonstrate that total blood volume changes occurring during neural activation are mainly due to arterial volume changes rather than venous volume changes. This implies that BOLD signal changes are due mostly to the mismatch between cerebral blood flow and oxygen consumption.