Neural activation increases blood flow locally. This vascular signal is used by functional imaging techniques to infer the location and strength of neural activity. However, the precise spatial scale over which neural and vascular signals are correlated is unknown. Furthermore, the relative role of synaptic and spiking activity in driving haemodynamic signals is controversial. Previous studies recorded local field potentials as a measure of synaptic activity together with spiking activity and low-resolution haemodynamic imaging. Here we used two-photon microscopy to measure sensory-evoked responses of individual blood vessels (dilation, blood velocity) while imaging synaptic and spiking activity in the surrounding tissue using fluorescent glutamate and calcium sensors. In cat primary visual cortex, where neurons are clustered by their preference for stimulus orientation, we discovered new maps for excitatory synaptic activity, which were organized similarly to those for spiking activity but were less selective for stimulus orientation and direction. We generated tuning curves for individual vessel responses for the first time and found that parenchymal vessels in cortical layer 2/3 were orientation selective. Neighbouring penet...Continue Reading
Fluctuations and stimulus-induced changes in blood flow observed in individual capillaries in layers 2 through 4 of rat neocortex
Columnar resolution of blood volume and oximetry functional maps in the behaving monkey; implications for FMRI
Localization of activity-dependent changes in blood volume to submillimeter-scale functional domains in cat visual cortex
Depth-resolved optical imaging and microscopy of vascular compartment dynamics during somatosensory stimulation
Fine detail of neurovascular coupling revealed by spatiotemporal analysis of the hemodynamic response to single whisker stimulation in rat barrel cortex
Experience with moving visual stimuli drives the early development of cortical direction selectivity
Cortical depth-specific microvascular dilation underlies laminar differences in blood oxygenation level-dependent functional MRI signal
Columnar specificity of microvascular oxygenation and blood flow response in primary visual cortex: evaluation by local field potential and spiking activity
The smallest stroke: occlusion of one penetrating vessel leads to infarction and a cognitive deficit
Improved blood velocity measurements with a hybrid image filtering and iterative Radon transform algorithm
Regional Blood Flow in the Normal and Ischemic Brain Is Controlled by Arteriolar Smooth Muscle Cell Contractility and Not by Capillary Pericytes
Transcranial Direct Current Stimulation Post-Stroke Upper Extremity Motor Recovery Studies Exhibit a Dose-Response Relationship
What is feasible with imaging human brain function and connectivity using functional magnetic resonance imaging
Mapping of the brain hemodynamic responses to sensorimotor stimulation in a rodent model: A BOLD fMRI study
Benchmarking laminar fMRI: Neuronal spiking and synaptic activity during top-down and bottom-up processing in the different layers of cortex
Multi-scale mapping along the auditory hierarchy using high-resolution functional UltraSound in the awake ferret
Blood oxygenation level dependent signal and neuronal adaptation to optogenetic and sensory stimulation in somatosensory cortex in awake animals
In vivo real-time imaging of cutaneous hemoglobin concentration, oxygen saturation, scattering properties, melanin content, and epidermal thickness with visible spatially modulated light
Propagation of BOLD Activity Reveals Task-dependent Directed Interactions Across Human Visual Cortex.
Differential effects of aquaporin-4 channel inhibition on BOLD fMRI and diffusion fMRI responses in mouse visual cortex
Structural and Microvascular Changes in the Macular Are Associated With Severity of White Matter Lesions
Neural Sources and Underlying Mechanisms of Neural Responses to Heartbeats, and their Role in Bodily Self-consciousness: An Intracranial EEG Study
Patterns of Cortical Visual Field Defects From Embolic Stroke Explained by the Anastomotic Organization of Vascular Microlobules
Intercellular Conduction Optimizes Arterial Network Function and Conserves Blood Flow Homeostasis During Cerebrovascular Challenges.
Average firing rate rather than temporal pattern determines metabolic cost of activity in thalamocortical relay neurons
Laminar specific fMRI reveals directed interactions in distributed networks during language processing
Functional ultrasound imaging of the brain reveals propagation of task-related brain activity in behaving primates
A proof-of-concept study for developing integrated two-photon microscopic and magnetic resonance imaging modality at ultrahigh field of 16.4 tesla
nNOS-expressing interneurons control basal and behaviorally evoked arterial dilation in somatosensory cortex of mice.
Effect of Repeated Anodal HD-tDCS on Executive Functions: Evidence From a Pilot and Single-Blinded fNIRS Study.
Time-dependent spatial specificity of high-resolution fMRI: insights into mesoscopic neurovascular coupling.
Assessing Uncertainty and Reliability of Connective Field Estimations From Resting State fMRI Activity at 3T.
Here is the latest research on barrel cortex, a region of somatosensory and motor corticies in the brain, which are used by animals that rely on whiskers for world exploration.