Final answer:
Homeostatic mechanisms in the brain maintain neural stability by adjusting cellular properties and synaptic scaling, particularly to preserve the excitatory and inhibitory balance in neuronal networks and prevent excitotoxicity.
Step-by-step explanation:
Homeostatic mechanisms in the brain adjust the cellular and synaptic properties of cortical networks to maintain stable levels of neural activity and compensate for changes in the environment. This adjustment is crucial for the survival and proper functioning of neurons. Synaptic scaling is one such mechanism, which involves changes in the properties of ion channels and the regulation of neurotransmitter receptors on the cell surface, such as NMDA and AMPA receptors. Homeostatic plasticity helps to preserve excitatory and inhibitory balance (E/I balance) within neuronal circuits, adapting to ongoing activity levels and preventing excitotoxicity. For instance, memantine, a partial and weak antagonist of NMDA receptors, has been shown to slow excitotoxic effects by its action on homeostatic mechanisms.
Understanding how cortical networks self-regulate through homeostatic plasticity is vital in unveiling the underlying pathophysiology and developing treatments for various neurological and neuropsychiatric disorders that upset the E/I balance.