Astrocytes interface both synapses and blood vessels, thus they are in the ideal position to mediate energy supply from the vasculature to neurons. The astrocyte-neuron lactate shuttle hypothesis has been proposed to outline a scheme in which blood-supplied glucose is converted to lactate in astrocytes and shuttled to neurons. However, the exact picture of this system is yet to be described. Moreover, astrocytes are known to store glucose in the form of glycogen, which has been recognized critical for memory formation. We will characterize the cerebral distribution of glycogen in various behavioral and pathological conditions to gain insight into the realistic organization of brain energy metabolism. Currently, we have established glycogen immunohistochemistry to assess the spatial distribution of glycogen in fixed tissues. Ultimately, we aim to monitor long-term changes of cerebral energy metabolism using multiple imaging modalities.