FIG. 2.
(A) Relations between neuroimaging signals (BOLD, CBF, and CBV) and neuronal activity (LFP, MUA). Evoked neuronal activity (LFP and MUA) show linear correlations with evoked neuroimaging signals (BOLD, CBF, and CBV) with increasing number of stimulus pulses at rates of 1.5 Hz (○) and 3 Hz (Δ). The multi-modal data suggest tight neurovascular coupling. (B) Dynamic comparison of ΔCMRO2 and LFP (for 3 Hz stimulation frequency). The dynamic correlation between the calculated ΔCMRO2 and the measured LFP suggests tight neurometabolic coupling. All data from (Herman et al., 2009) and (Sanganahalli et al., 2009). BOLD, blood oxygenation level-dependent; CBF, cerebral blood flow; CBV, cerebral blood volume; LFP, local field potential; MUA, multi-unit activity.