A pathological process in which neurons are damaged or killed due to overstimulation by excitatory neurotransmitters, mainly glutamate. Hyperactivation of receptors causes an excessive influx of calcium ions into cells, which triggers a cascade of damage and death of neurons. Excitotoxicity plays a role in acute brain injuries (stroke, traumatic brain injury) and chronic neurodegenerative diseases (Alzheimer’s, Parkinson’s, ALS).