The orbicularis oculi muscle is the primary muscle responsible for blinking. It's a circular muscle that surrounds the eye and helps close the eyelids.
The orbicularis oculi has three parts:
- Orbital part: This part is responsible for forceful closure of the eyelids, such as when you squint or close your eyes tightly.
- Palpebral part: This part helps with gentle closure, like when you blink normally.
- Lacrimal part: This part helps pump tears from the tear sac into the nasal cavity.
The levator palpebrae superioris muscle is another muscle involved in eyelid movement, but its primary function is to lift the upper eyelid, opening the eye.
During blinking, the orbicularis oculi muscle contracts, closing the eyelids, while the levator palpebrae superioris relaxes. This coordinated action allows for efficient blinking.
