Traumatic brain injury refers to visible injuries to the head or brain caused by external forces, typically resulting in serious consequences. Such injuries often lead to varying degrees of permanent functional impairment, depending largely on whether the damage is localized to a specific area of the brain (focal) or diffuse. Damage in different brain regions can cause different symptoms, with focal symptoms including motor, sensory, speech, visual, and auditory abnormalities. Meanwhile, diffuse brain damage commonly affects memory, sleep, or can lead to confusion and coma.