Figure 21.

SPW‐R‐triggered multi‐structure BOLD activity. (A) Time–frequency representation of the SPW‐R events in the macaque monkey under anesthesia. (B) Average activation maps. Positive BOLD response is observed in the neocortex and limbic cortex, while activity suppression of BOLD signal is seen in the diencephalon, mesencephalon and metencephalon. (C) Time courses of each group each region of interest (ROI). Note the sign change in the transition from cortical to subcortical areas and the differences in response onset. (D) Fractions of activated voxels for each region of interest. The blanket reduction of the BOLD signal in subcortical structures, however, do not mean suppression of spiking activity (see text). Reproduced from Logothetis (2015).