Differences in neurovascular coupling in areas with positive and negative BOLD signal
نویسندگان
چکیده
Introduction While the dynamics and mechanism of the positive BOLD response have been well studied, much less is known about the mechanism of the negative BOLD response. Although the negative BOLD response is related to decreases in neural activity [1] and in CBF [2], the temporal dynamics differ from that of the positive BOLD signal [1]. Here, we studied the properties of the negative BOLD response in greater detail by comparing the BOLD-, functional CBVand CBFresponses in regions exhibiting positive and negative BOLD in primary visual cortex (V1) of anesthetized monkeys.
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