Mechanisms of Brain Injury

Primary Injury

The primary or immediate injury disrupts the chemical responsible for brain functions, which in turn produces an altered state of consciousness and explains many of the symptoms associated with an initial injury.

Internal injuries such as cerebral vascular accidents (when blood vessels become clogged), infections, brain tumors or oxygen depravation.

External injuries or injuries caused by a force outside of the body, such as a blow to the head or face, deceleration, head/neck rotation, cavitation (shock wave through brain matter) or diffuse axonal injury which is the tearing of brain nerve fibers.


Once the initial injury occurs secondary injury evolves and can complicates the primary injury. Primary brain injury is a complete and nonreversible event that triggers a series of subsequent neuro-electro-chemical cascade events (secondary injury) that ultimately end in neuronal cell death. Cascade events include disrupted blood flow (emboli or hemorrhage), swelling (cellular edema), impairment of neuronal chemical messengers and how the brain uses energy sources.

Brain injury is not just an event.  It causes chronic physical, cognitive and mental health issues, and is not a “treat with meds and it will all get better” situation.