In short: The brain is mainly made up of a network of neurons and astrocytes. The neurons conduct the excitations, the astrocytes perform auxiliary tasks and influence the neurons. Brain researcher Prof. Gerhard Roth explains this clearly: the astrocytes are the servants for the neurons.
The fact is, the neurons are nourished by way of astrocytes and this is costly. An astrocyte feeds many neurons and a neuron is nourished by many astrocytes. There is still no plausible explanation for the amount of astrocytes. After all, about 50% of all brain cells are astrocytes. The nutrient reserves in the astrocytes are low. As a result, if one neuron consumes a lot, the other neurons supplied have less. The neurons have to share the nutrients (there would be no problem if they were taken directly from the bloodstream). The supplied neurons are energetically dependent on the nutrient reservoirs. Now with these thoughts it is the other way round: now the neurons are the servants. The neurons do the work (excitation conduction) and the astrocytes evaluate this by means of many small nutrient reservoirs. This now in detail in language german.

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Stefan Pschera
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