Adrenaline is also known as epinephrine. It’s a hormone found in the blood and brain. It’s essential to the fight-or-flight response - it increases alertness, increases blood flow to your muscles, dilates your pupils, dulls the sensation of pain, and may make possible great feats of strength.
Adrenaline is associated with fear. It’s produced in response to stress by the sympathetic nervous system.
You can get hits of adrenaline by:
- Riding a thrill ride
- Watching a scary movie
- Deliberate cold exposure
Source
- Huberman Labs
- Wikipedia