Final answer:
Choking prevents the flow of air into the lungs, leading to a decrease in oxygen supply to the brain. This causes increased pressure in the head, resulting in severe headaches and potential brain damage.
Step-by-step explanation:
When you choke yourself, pressure builds up in your head due to the obstruction of the flow of air. Choking prevents breathing and may result in asphyxia or suffocation. The mechanical obstruction of airflow into the lungs causes a decrease in oxygen supply to the brain, leading to increased pressure in the head. This increase in pressure can cause severe headaches, constricted blood flow, and serious damage to the brain.