Modeling the Temporal Dynamics of the Positive and Negative BOLD Response
Behzadi y, Liu T
As compared to the positive BOLD responses, the negative BOLD responses exhibited greater initial delays, faster rise times, increased peak amplitudes, and a less pronounced post-stimulus undershoot. In this work, we examine the dynamics of the positive and negative BOLD responses using an arteriolar compliance model of the cerebral blood flow response (CBF)coupled with a Balloon model of the venous compartment. The model simulations suggest that the observed differences may be a result of the varying contribution of smooth muscle compliance during increases and decreases of neural activity.