Performing complex cognitive tasks leads to glutamate accumulating in a key region of the brain, a study finds, which could explain why mental labor is so exhausting.
So-called mossy fiber synapses in the hippocampus can meter the amount of neurotransmitter they receive by sending glutamate against the usual direction of synaptic flow.
In an unexpected twist in neuroscience dogma, the cells on the receiving end of neurotransmission appear to be able to release glutamate to regulate the transmitting cell’s activity.