Life SciencesBiochemistryPhysiologyBioenergeticsCellular MetabolismMetabolismBrain Energy MetabolismCerebral PhysiologyEnergy MetabolismMetabolic RateNeuronal MetabolismTricarboxylic Acid CycleBrain Energy SensingBrain Fuel Utilization During FastingCerebral Glucose UtilizationCerebral Metabolic RateRegional Brain Metabolism