Andrew Huberman· PhD
it's simply a collection of brain structures, not one brain structure, but a collection of brain structures that generally are responsible for shifting the overall state that we're in from states of more relaxed and calm to states of more alert and focused. The limbic system is intimately related to the so-called autonomic nervous system, which regulates our sleep wake cycles and a number of other things like our digestion, et cetera, our level of hunger and on and on.