Has anyone ever told you that you looked sad or tired when you weren’t? If the problem isn’t your mood, it might be your face, according to a study in the medical journal Plastic and Reconstructive Surgery.

Yale University researchers set out to determine how facial features like eyebrow shape, eyelids and wrinkles affect facial expressions. They took a photo of a woman’s eyes and digitally altered it to change the eyebrow or lid shape or add wrinkles. After producing 16 different versions of the same face, they asked 20 study participants to rate, on a scale of 0 to 5, the presence of seven expressions or emotions: tiredness, happiness, surprise, anger, sadness, disgust and fear.

What was surprising about the study is that many of the pictures that mimicked various plastic surgery procedures, such as eyelid surgery or brow lifts, actually generated worse scores, with study participants rating those faces as looking angry or tired.

For instance, drooping of the upper eyelid was the biggest indicator of tiredness, but a picture that simulated a type of eyelid surgery — involving the removal of excess skin from the upper eyelid — made the woman look even more tired and sad, the study participants reported. Raising the upper eyelids produced an increase in the perception of surprise and fear.

“A significant number of plastic surgery patients opt for eyelid surgery, forehead lifts and face-lifts not only for rejuvenative reasons, but to change an unattractive facial expression as well,” said Dr. John A. Persing, one of the study authors. “Our findings indicate that moderation is best when removing excess skin in the upper eyelid. You do not want to create an overdone look that actually makes you look more tired.”

Eyebrows made a big difference in how people perceived the mood of the woman in the picture. When the brows were lowered or slanted toward the nose, or when forehead wrinkles were added, ratings of anger and disgust increased.

Also, raising the outer corner of the eyebrows produced an increase in the perception of surprise. Raising the inner corner of the eyebrows away from the nose was perceived as a sad facial expression.

According to the American Society of Plastic Surgeons, more than 241,000 eyelid surgeries, 43,000 forehead lifts and 118,400 face-lifts were performed in 2007. But the study shows that people contemplating eye surgery should talk to their doctor about how a procedure might affect their facial expressions. And some people might want to think twice about eliminating some sets of wrinkles. One digitally-altered picture added crows’ feet — tiny wrinkles around the eyes — and received high ratings for “happiness.'’

“The eyes and their related structures nonverbally communicate a wide range of expressions that are universal to all people,” Dr. Persing said. “Therefore facial expression should be a factor in how patients and their plastic surgeons select various rejuvenation procedures. As our findings show, even the slightest modification can elicit profound changes in how others perceive us.”

有没有这种情况？有人说你看起来悲伤或很疲倦，可是你实际并不是这样。修复重建与整形外科杂志中登出一项研究成果表明, 如果你的心情并不是这样，可能是你的面部表情"惹的祸"。

耶鲁大学的学者们开始研究脸部特征如眉毛的形状，眼皮和皱纹如何影响面部表情。他们拍下了一位女士眼睛的照片，然后通过数码技术改变眉毛,眼皮的形状或者增添一些眼角皱纹, 在同一张脸上制出十六张不同效果的照片，他们请20个人从0到5的范围内打分评价七种表情或者情绪：疲倦，高兴，惊讶，生气，悲伤，厌恶和恐惧。

出乎意料的是, 许多副照片其实是模仿不同的整容手术程序作出来的，象眼皮手术或者提眉，而这些手术实际产生的效果并不尽如人意，人们给出的评价是整形过的脸看上去有的是愤怒,有的则显出疲惫。

例如，上眼皮耷拉下来最能代表疲倦，但是一副照片是模仿一种眼皮手术-----从上眼皮除去多余的皮肤-----人们评价这样使人看起来更疲惫或者沮丧。提高上眼皮则让人呈现惊奇和恐惧的表情。

“大量的整容手术患者选择双眼皮手术，提额和面部除皱，不只是为了青春常驻，还是为了改善面部表情。我们发现去除上眼皮多余的皮肤时最好适可而止。不要去除得太多，否则会使你看起来更没有精神。”这项研究的作者约翰波森博士说。

眉毛在人们解读他人的心情上意义重大。如果眉毛低垂或者向鼻子方向倾斜，或者额头上的皱纹增加，说明生气或者厌恶情绪。

还有就是眉毛的外缘提升会显得惊奇，内缘提升与鼻子的距离拉长则让人显得悲伤。

美国整形外科学会提供数据表明，2007年共做了241000例眼皮额手术，43000例提额手术和118400例面部除皱手术。但是研究表明，想要做眼部手术的人应该与医生谈谈, 明白他们将要进行的手术会怎样影响他们的面部表情。想要除去皱纹的人也要三思而行，因为一幅照片用数码技术增加了眼角纹的长度----结果人们普遍评价照中人的情绪是“快乐”。

“眼睛及周围的肌肉无声地表达了许多种情绪，们们对这些情绪的理解是共通的。因此要做面部整容手术的人在选择手术程序时，应该将面部表情作为主要考虑因素。因为研究发现，即使是很微小的修改也会改变人们对我们的心情的看法。”