Brain Parenchymal fMRI Signals During Cortical Spreading Depression

Joonas Arttu Autio¹, ², Artem Shatillo¹, Rashid Giniatullin¹, Olli Grhn¹

Using functional magnetic resonance imaging (fMRI) of the rat brain we found a novel type of parenchymal fMRI signals during large increases in metabolism. Cortical spreading depression (CSD), a self-propagating wave of tissue depolarization, associated with several pathological conditions such as migraine and stroke, was used as paradigm to evoke enhanced brain metabolism. The underlying CSD activated signal changes were investigated using spin-lock (SL), T1 relaxation in the rotating frame (T1), weighted fMRI. Our results show that during CSD propagation SL-fMRI signal is generated by endogenous parenchymal mechanisms.