Several aspects of the proposal, which aims to expand open access, require serious discussion and, in some cases, a rethink.
Image credit: Dave Cutler (artist).
New Research In
Physical Sciences
Featured Portals
Articles by Topic
Biological Sciences
Featured Portals
Articles by Topic
Abstract
Coupling between cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) was studied using multiple sequential administrations of 15O-labeled radiotracers (half-life, 123 sec) and positron emission tomography. In the resting state an excellent correlation (mean r, 0.87) between CBF and CMRO2 was found when paired measurements of CBF and CMRO2 from multiple (30-48) brain regions were tested in each of 33 normal subjects. Regional uncoupling of CBF and CMRO2 was found, however, during neuronal activation induced by somatosensory stimulation. Stimulus-induced focal augmentation of cerebral blood flow (29% mean) far exceeded the concomitant local increase in tissue metabolic rate (mean, 5%), when resting-state and stimulated-state measurements were obtained in each of 9 subjects. Stimulus duration had no significant effect on response magnitude or on the degree of CBF-CMRO2 uncoupling observed. Dynamic, physiological regulation of CBF by a mechanism (neuronal or biochemical) dependent on neuronal firing per se, but independent of the cerebral metabolic rate of oxygen, is hypothesized.
Focal physiological uncoupling of cerebral blood flow and oxidative metabolism during somatosensory stimulation in human subjects
Sign up for Article Alerts
Jump to section
You May Also be Interested in
Several large or long-lived animals seem strangely resistant to developing cancer. Elucidating the reasons why could lead to promising cancer-fighting strategies in humans.
Image credit: Shutterstock.com/ronnybas frimages.
PNAS Profile of NAS member and biochemist Hao Wu
A study suggests a putative gene-expression hallmark common to monogamous male vertebrates of some species, namely cichlid fishes, dendrobatid frogs, passeroid songbirds, common voles, and deer mice, and identifies 24 candidate genes potentially associated with monogamy.
Image courtesy of Yusan Yang (University of Pittsburgh, Pittsburgh).
Physical and social well-being in old age are linked to self-assessments of life worth, and a spectrum of behavioral, economic, health, and social variables may influence whether aging individuals believe they are leading meaningful lives.
Image courtesy of Pixabay/MabelAmber.
More Articles of This Classification
Related Content
Cited by...
- Genetically defined cellular correlates of the baseline brain MRI signal
- Neurovascular dysfunction in dementia - human cellular models and molecular mechanisms
- Prefrontal oxygenation correlates to the responses in facial skin blood flows during exposure to pleasantly charged movie
- Respiration-Deficient Astrocytes Survive As Glycolytic Cells In Vivo
- Foliage Plants Cause Physiological and Psychological Relaxation as Evidenced by Measurements of Prefrontal Cortex Activity and Profile of Mood States
- Impaired cerebral blood flow and oxygenation during exercise in type 2 diabetic patients
- Impact of puberty on the evolution of cerebral perfusion during adolescence
- Stability of cerebral metabolism and substrate availability in humans during hypoxia and hyperoxia
- Coupling blood flow and neural function in the retina: a model for homeostatic responses to ocular perfusion pressure challenge
- Coupling of functional connectivity and regional cerebral blood flow reveals a physiological basis for network hubs of the human brain
- PET/MRI for Neurologic Applications
- "Overshoot" of O2 Is Required to Maintain Baseline Tissue Oxygenation at Locations Distal to Blood Vessels
- Absolute Quantification of Oxygenated Hemoglobin within the Visual Cortex with Functional Near Infrared Spectroscopy (fNIRS)
- Nonlinear coupling between cerebral blood flow, oxygen consumption, and ATP production in human visual cortex
- Attenuation of Cerebral Venous Contrast in Susceptibility-Weighted Imaging of Spontaneously Breathing Pediatric Patients Sedated with Propofol
- Evidence for a vascular contribution to diffusion FMRI at high b value
- A coherent neurobiological framework for functional neuroimaging provided by a model integrating compartmentalized energy metabolism
- Theoretical model of temperature regulation in the brain during changes in functional activity
- Neuron-glia metabolic coupling and plasticity
- Synchronization between background activity and visually evoked potential is not mirrored by focal hyperoxygenation: implications for the interpretation of vascular brain imaging.
- Brain lactate kinetics: Modeling evidence for neuronal lactate uptake upon activation
- Separate Spatial Scales Determine Neural Activity-Dependent Changes in Tissue Oxygen within Central Visual Pathways
- Coupling of the cortical hemodynamic response to cortical and thalamic neuronal activity
- Temporal Dependence in Uncoupling of Blood Volume and Oxygenation during Interictal Epileptiform Events in Rat Neocortex
- Neuroimaging With Calibrated fMRI
- Columnar Specificity of Microvascular Oxygenation and Volume Responses: Implications for Functional Brain Mapping
- Increased lactate/pyruvate ratio augments blood flow in physiologically activated human brain
- NADH augments blood flow in physiologically activated retina and visual cortex
- The Underpinnings of the BOLD Functional Magnetic Resonance Imaging Signal
- Functional Brain Imaging and Human Brain Function
- Appraising the brain's energy budget
- Increase in focal concentration of deoxyhaemoglobin during neuronal activity in cerebral ischaemic patients
- Hemodynamic Response Changes in Cerebrovascular Disease: Implications for Functional MR Imaging
- Changes in Blood Flow and Oxygen Metabolism During Visual Stimulation in Carotid Artery Disease: Effect of Baseline Perfusion and Oxygen Metabolism
- Activation-Induced Resetting of Cerebral Metabolism and Flow Is Abolished by {beta}-Adrenergic Blockade With Propranolol
- Metabolic and electrophysiological validation of functional MRI
- In Vivo Detection of Postictal Perturbations of Cerebral Metabolism by Use of Proton MR Spectroscopy: Preliminary Results in a Canine Model of Prolonged Generalized Seizures
- The Effect of Acute Hypoglycemia on Brain Function and Activation: A Functional Magnetic Resonance Imaging Study
- Imaging in epilepsy: a paediatric perspective
- Blood flow and oxygen delivery to human brain during functional activity: Theoretical modeling and experimental data
- The Role of Functional MR Imaging in Patients with Ischemia in the Visual Cortex
- Cerebral energetics and the glycogen shunt: Neurochemical basis of functional imaging
- A default mode of brain function
- Functional MRI at 1.5 tesla: A comparison of the blood oxygenation level-dependent signal and electrophysiology
- Coupling between changes in human brain temperature and oxidative metabolism during prolonged visual stimulation
- Functional MRI cerebral activation and deactivation during finger movement
- Changes in cerebral blood oxygenation of the frontal lobe induced by direct electrical stimulation of thalamus and globus pallidus: a near infrared spectroscopy study
- MR Blood Oxygenation Level-Dependent Signal Differences in Parenchymal and Large Draining Vessels: Implications for Functional MR Imaging
- Neuronal activity alters local blood flow in brain tumour adjacent to the activating cortex
- Tracking neuronal fiber pathways in the living human brain
- Linear coupling between cerebral blood flow and oxygen consumption in activated human cortex
- Determination of Cognitive Hemispheric Lateralization by "Functional" Transcranial Doppler Cross-Validated by Functional MRI
- Retinotopic mapping of lateral geniculate nucleus in humans using functional magnetic resonance imaging
- Actions of Caffeine in the Brain with Special Reference to Factors That Contribute to Its Widespread Use
- An Increase in Lactate Output by Brain Tissue Serves to Meet the Energy Needs of Glutamate-Activated Neurons
- Imaging of H217O distribution in the brain of a live rat by using proton-detected 17O MRI
- Mental chronometry using latency-resolved functional MRI
- Language-Activated Cerebral Blood Oxygenation and Hemodynamic Changes of the Left Prefrontal Cortex in Poststroke Aphasic Patients : A Near-Infrared Spectroscopy Study
- Calibrated functional MRI: Mapping the dynamics of oxidative metabolism
- A neural system for human visual working memory
- Behind the scenes of functional brain imaging: A historical and physiological perspective
- Pilot Study of Functional MRI to Assess Cerebral Activation of Motor Function After Poststroke Hemiparesis
- Functional Anatomic Studies of Memory Retrieval for Auditory Words and Visual Pictures
- Interactions Between Electrical Activity and Cortical Microcirculation Revealed by Imaging Spectroscopy: Implications for Functional Brain Mapping
- What Words Are Telling Us about the Brain
- Functional Brain Imaging Studies of Cortical Mechanisms for Memory
- Magnetic Resonance Imaging of Regional Cerebral Blood Oxygenation Changes Under Acetazolamide in Carotid Occlusive Disease
- Nonoxidative glucose consumption during focal physiologic neural activity
- Cerebral energetics and the glycogen shunt: Neurochemical basis of functional imaging
- Functional MRI at 1.5 tesla: A comparison of the blood oxygenation level-dependent signal and electrophysiology
- Blood flow and oxygen delivery to human brain during functional activity: Theoretical modeling and experimental data