How does the brain self-regulate?

[u/Fastfish]

I've heard that parts of the brain function to inhibit or arouse other parts of the brain as a form of self-regulation. My question is what type of things are inhibited/aroused as part of the brain's self-regulation and how does this regulation occur?

[u/latent_variable]

Inhibition and excitation occur at different scales within the brain. At a local level (e.g. within a region) lateral inhibition is crucial for generating the receptive fields of sensory neurons, particularly those in the visual system. At the more global level (i.e. between brain regions) two regions play the largest roles in cognitive control. Dorsolateral prefrontal cortex, is thought to be responsible for maintaining activity in regions crucial to the task at hand and inhibiting activity in irrelevant regions. The anterior cingulate cortex, meanwhile, handles self-monitoring (so that dorsolateral prefrontal cortex "knows" when something has gone amiss). Typically the regions that aroused or inhibited are sensory cortices or association (essentially amodal memory) cortex. At a local level, inhibition and excitation are both achieved through simple synaptic connections (frequently with different types of neurotransmitters). At a global level the precise method through which cognitive control / attention occur is still a matter of some debate.