學會如何微笑，這纔是自拍的正確打開方式

We all have our own idea of what the perfect smile should look like, whether we show a mouthful of pearly whites or keep our lips closed and turned up at the corners just so. New research suggests that there really is a proper way to smile, and it has everything to do with facial expression.
完美的微笑應該是什麼樣子的呢，是露出一口大白牙，還是抿起雙脣並使嘴角上揚，對此我們都有自己的想法。一項新研究指出，確實是有正確的微笑方式的，而且這與面部表情密切相關。

When we think of the perfect smile, we often envision a wide, beaming grin, with all of our teeth showing. However, Nathaniel Helwig and his colleagues at the University of Minnesota discovered that a genuine smile actually rests less on showing teeth and more on facial balance and symmetry .
當我們想起完美的微笑的時候，我們往往想象的是喜氣洋洋且露出所有牙齒的微笑。然而，明尼蘇達大學的納撒尼爾·赫爾維希和他的同事們發現，真正的微笑實際上並不在於露出幾顆牙齒，而更多地在於面部表情的均衡和對稱。

Researchers looked at 3D computer-animated facial models of more than 800 participants. The computer-animated facial models underwent a series of facial transformations, with researchers changing the mouth angle, amount of teeth shown, the extent of the smile, and how symmetrical the smile was. Participants were then asked to rate the models’ smiles based on effectiveness, genuineness, pleasantness, and perceived emotional intent.
研究人員着眼於800多位參與者的3D電腦動畫面部模型。他們爲這些模型做了一系列的面部轉換，改變了這些模型嘴角的弧度、露出的牙齒的數量、微笑的程度以及微笑的對稱度。然後參與者被要求基於有效性、真誠度、愉悅感以及所領會到的情感意圖來爲這些模型的微笑評分。

The results of the study found that the most successful smile—one that was rated most pleasant, genuine, and effective—had a perfect balance of teeth, an ideal mouth angle, and a smile length that extended to what was dubbed the “sweet spot.” Smiles that demonstrated a quick sync of the left and right side of the face during smiling were also more highly related.
研究發現，最成功的微笑，也就是那個被評爲最令人愉快、最真誠、最有效的微笑，它所展現的牙齒非常勻稱，嘴角的弧度十分完美而且微笑的時間也被認爲是“最合適的”。微笑的時候，臉部兩邊的快速同步也與此密切相關。

As Science Daily notes, smiling makes up a good portion of our nonverbal communication, making it important to have a grin that will draw people to you and also seem sincere. It’s also worth noting that perfect smile could help improve your health too.
《每日科學雜誌》指出，微笑在我們的非語言交流中佔據着很高的比例，面帶微笑會吸引着人們來到你的身邊，還會使你顯得真誠，而這也使微笑變得尤爲重要。值得注意的是，完美的微笑可能還有助於改善你的健康。