Neural regulation of cerebral blood flow is a complex process that involves coordination between neural activity, blood vessels, and metabolic factors. Here is a detailed summary based on the provided sources:
Neural activity leads to increased cerebral blood flow to active regions through neurovascular coupling. When neurons are active, they utilize more oxygen and glucose, which triggers vasodilation of local blood vessels to deliver more blood to that area [1]. The mechanism linking neural activity to vasodilation is not fully understood, but may involve release of signaling molecules like nitric oxide or prostaglandins from active neurons and astrocytes [3].
Beyond neurovascular coupling, the brain uses additional mechanisms to regulate blood flow. Cerebral autoregulation maintains steady blood flow over a range of blood pressures through myogenic constriction/dilation of arterioles and metabolic feedback [5]. The autonomic nervous system can also influence cerebral blood flow – sympathetic activation during stress shifts the autoregulation curve to higher pressures [2].
Changes in cerebral blood flow are used to make inferences about regional brain activity with neuroimaging techniques like PET and fMRI. These measure overall activity rather than firing of individual neurons, so cannot distinguish excitatory and inhibitory processes [4].
Sources:
- Toates, F. M. (2005). Biological psychology (3rd ed.). Nelson Thornes.
- Mason, P. (2011). Medical neurobiology. Oxford University Press.
- Bechtel, W. (2008). Mental mechanisms: Philosophical perspectives on cognitive neuroscience. Psychology Press.
- Panksepp, J., & Biven, L. (2012). The archaeology of mind: Neuroevolutionary origins of human emotions. W.W. Norton & Company.
- Mason, P. (2011). Medical neurobiology. Oxford University Press.
- Guenther, F. H. (2016). Neural control of speech. MIT Press.