Gunshot to the Head Effects

Overview

This lecture analyzes what physically and biologically happens when someone is shot in the head, why death isn't always instant, and what factors influence survival or fatality.

Physics and Anatomy of a Gunshot to the Head

• When the trigger is pulled, the firing pin ignites the primer, causing an explosion that propels the bullet.
• The bullet's pointed tip helps it penetrate skin, bone, and brain tissue by concentrating kinetic energy.
• A bullet entering the skull causes a traumatic brain injury (TBI) and creates a permanent cavity in the brain.
• The injury can be a penetrating wound (bullet stays) or a perforating wound (bullet passes through).

Biological Effects and Fatality Factors

• A bullet creates pressure waves and cavitation, stretching and damaging tissues beyond its direct path.
• Shockwaves can cause brain swelling, rupture blood vessels, and increase intracranial pressure, often leading to death.
• Bullet type, caliber, trajectory, and entry point critically affect injury severity and likelihood of survival.
• Gunshot wounds to the head are fatal about 90% of the time; most victims die instantly or at the scene.
• Hitting vital brain regions or major blood vessels almost always leads to immediate death.

Rare Survival and Brain Recovery

• Some victims, like Ahad Israfil, survive severe gunshot wounds due to factors like bullet path and prompt care.
• Surviving with one damaged hemisphere can leave motor and sensory deficits but may preserve certain functions.
• The human brain can sometimes adapt to severe injury, but survival depends on many favorable factors.

Hollywood Myths vs. Reality

• Media often misrepresents gunshot deaths as either always instant or survivable, but reality includes a range of outcomes.
• Survival is rare and requires a combination of low-caliber weapon, non-vital injury, distance, and rapid medical treatment.

Key Terms & Definitions

• Cartridge — The full ammunition unit, including bullet, casing, propellant, and primer.
• Bullet — The projectile portion of ammunition that is fired from a gun.
• Traumatic Brain Injury (TBI) — Brain damage caused by external force, such as a bullet.
• Penetrating Wound — Bullet enters but does not exit the body.
• Perforating (Through-and-Through) Wound — Bullet enters and exits the body.
• Cavitation — The temporary cavity created by the bullet’s passage and shockwave in tissue.

Action Items / Next Steps

• Review types of brain injuries and causes for next lesson.
• Watch supplemental video: "What Happens When You Die?"