Brain complexity: Consciousness, brain 42% active (Introduction)

by David Turell , Friday, May 27, 2016, 14:41 (3102 days ago) @ David Turell

An amazing study using radioactive glucose on patients in various states of consciousness and normal controls finds consciousness requires 42% of the brain must be active. Glucose is the brain's fuel:-http://www.the-scientist.com/?articles.view/articleNo/46175/title/Quantifying-Consciousness/&utm_campaign=NEWSLETTER_TS_The-Scientist-Daily_2016&utm_source=hs_email&utm_medium=email&utm_content=30023521&_hsenc=p2ANqtz-_m2MWMeq2tvPluxBmYMTWS3sZ0pMe67UAippNDSqyz-yW07f4wHOlUCaURQ1Q_NVsqmG3uNddGo_nwChk82JO8gYrYJQ&_hsmi=30023521/-"Differentiating states of consciousness in brain-injured patients is a major challenge for clinicians. Researchers from the University of Copenhagen, Denmark, and their colleagues recently used positron emission tomography (PET) to measure the metabolism of glucose in the brains of 131 patients, finding that 42 percent of normal cortical function is the minimum amount of energy required for conscious awareness. The findings provide “a simple and objective metabolic marker” of consciousness, the authors wrote in their study, published today (May 26) in Current Biology.-***-"In the present study, Kupers and colleagues conducted PET imaging on 131 patients with disorders of consciousness and 28 healthy controls. This involves injecting glucose labeled with a radioactive tracer into the bloodstream to measure sugar uptake in an organ—in this case, the brain. To account for differences among individuals, the researchers normalized glucose uptake in the brain with that of surrounding tissue.-"Kupers's team identified a sharp cutoff for regaining consciousness of 42 percent of the normal, healthy metabolic rate. One year after the PET study, the brain's metabolic rate predicted the return of awareness for 94 percent of the patients in the study, the researchers reported. In addition, regional differences in glucose metabolism (relative to whole-brain metabolism) correlated with the patients' likelihood of regaining certain cognitive functions, such as vision and language comprehension, the team showed.-"In the present study, Kupers and colleagues conducted PET imaging on 131 patients with disorders of consciousness and 28 healthy controls. This involves injecting glucose labeled with a radioactive tracer into the bloodstream to measure sugar uptake in an organ—in this case, the brain. To account for differences among individuals, the researchers normalized glucose uptake in the brain with that of surrounding tissue.-"Kupers's team identified a sharp cutoff for regaining consciousness of 42 percent of the normal, healthy metabolic rate. One year after the PET study, the brain's metabolic rate predicted the return of awareness for 94 percent of the patients in the study, the researchers reported. In addition, regional differences in glucose metabolism (relative to whole-brain metabolism) correlated with the patients' likelihood of regaining certain cognitive functions, such as vision and language comprehension, the team showed.-***-"The take-home message . . . is that consciousness is a highly energy demanding process, involving the brain at large,” Kupers said in the statement. “This fundamental physiological trait can help clinicians determine the potential for recovery of awareness in patients suffering from severe brain injuries of any kind.'”-Comment: It is not difficult to understand that a flat EEG means unconsciousness, making observed flat EEG patients who have had NDE's more significant.