Smiles : Genuine and Fake

Genuine Smile involves both voluntary and involuntary contraction from two muscles: the zygomatic major (raising the corners of the mouth) and the orbicularis oculi (raising the cheeks and producing crow's feet around the eyes).

Fake Smile or ‘Say Cheese’ smile involves the contraction of just the zygomatic major since we cannot voluntarily contract the orbicularis oculi muscle.

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