Columnar specificity of microvascular oxygenation and blood flow response in primary visual cortex: evaluation by local field potential and spiking activity.
The relation of cortical microcirculation, oxygen metabolism, and underlying neuronal network activity remains poorly understood. Anatomical distribution of cortical microvasculature and its relationship to cortical functional domains suggests that functional organizations may be revealed by mapping cerebral blood flow responses. However, there is little direct experimental evidence and a lack of electrophysiological evaluation. In this study, we mapped ocular-dominance columns in primary visual cortex (V1) of anesthetized macaques with capillary flow-based laser speckle contrast imaging and deoxyhemoglobin-based intrinsic optical imaging. In parallel, the local field potentials (LFPs) and spikes were recorded from a linear array of eight microelectrodes, carefully positioned into left and right eye columns in V1. We found differential activation maps of blood flow, after masking large superficial draining vessels, exhibited a column-like pattern similar as the oximetric maps. Both the activated spikes and γ-band LFP demonstrated corresponding eye preference, consistent with the imaging maps. Our results present direct support in favor of previous proposals that the regulation of microcirculation can be as fine as the submillimeter scale, suggesting that cortical vasculature is functionally organized at the columnar level in a manner appropriate for supplying energy demands of functionally specific neuronal populations.
Department of Psychology, Vanderbilt University, Nashville, Tennessee 37212, USA.
Zheng
Z
Wang
Anna W
AW
Roe
D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D001931:Brain Mapping / Q000379:methods*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D023882:Dominance, Ocular / Q000502:physiology; D006454:Hemoglobins; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D008833:Microcirculation / Q000502:physiology; D055806:Microvessels / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology*; D010775:Photic Stimulation; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D014793:Visual Cortex / Q000098:blood supply* / Q000502:physiology; D056969:Voltage-Sensitive Dye Imaging
D006454:Hemoglobins; C100003:deoxyhemoglobin