In the past decade, scientists have made the facial transplants a reality. Now, surgeons can give someone an entirely new, functioning face grafted from a deceased donor. But after these initial successes, came new questions for the first wave of patients. Can a new face accurately display the way the recipient feels?

It takes time and training, but a transplanted face is capable of the movements needed to convey our innermost emotions, according to a study published Wednesday in JAMA Network Open.

In a small sample of six patients who underwent full facial or partial facial transplants, a team at Brigham and Women’s Hospital found that they were able to reliably express happiness, sadness, anger, surprise, fear, and disgust after undergoing a face transplant.

Not all emotions can be expressed equally. There were only small, but detectable improvements in sadness, anger, surprise, fear, and disgust. But the expression of happiness recovered to about 43 percent to that of healthy controls. These emotions were captured and analyzed with video software.

Dr. Miguel Dorante, the study’s first author, tells Inverse that this is finding is relevant to the next wave of facial transplant research.

Now that the basic anatomy of a face can be restored, scientists are investigating how patients can use that new face to express their personal concept of a smile, or their idea of a frown, using those new parts. Adjusting to a new face is a considerable challenge. The ability to layer one’s emotional identity upon a new face can make all the difference.

“In essence, everybody has a face with the necessary hardware that makes it a face,” says Dorante. “But the individual parts are as diverse as all of us and the way that we use them is just as diverse — and coded by our experiences and cultures.”

Not just a smile, your smile

In the study, Dorante describes the process of face transplantation in terms of hardware and software.

The hardware is the face itself — once the body’s immune system accepts the new face, you’ve successfully installed the new hardware.

As of 2018, about 40 face transplants have been done worldwide, suggesting that scientists are getting better at the procedure. But even now, there are questions as to whether that new face is capable of lasting a lifetime.

To add to that, this decade’s challenge will be to push the procedure further, uncover the psychological and emotional components of having a new face, and find solutions to related challenges.

That’s where what Dorante calls software comes in. That software is the personal interpretation of something like a smile — “something that’s learned over a lifetime,” he says.

For example, Dorante says to look at the way that the distinct way Dwayne “The Rock” Johnson raises his eyebrows. Maybe you were inspired by that gif-worthy expression and somewhere during your life, incorporated it into your own facial expressions.

“Emotional expressions are ‘coded” and often we can’t really access that code when prompted to because it is unique to the person and their cultural experiences,” says Dorante.

This study shows that, after facial transplant, patients are able to manipulate their new faces into recognizable emotions (your standard-issue smile, for instance). Dorante says the patients initially found this difficult and laughed at being asked to make comically angry or happy faces.

"If their code runs smoothly, the hardware will react and make the expression they want.”

However, Dorante explains that asking patients to do this is a first step towards accessing a deeper level of emotional expression — that software level. He likens emotions to code, that can be used by the “hardware” of a new face.

“That is why we asked the patients to make motor movements that are necessary for the emotional expressions to test whether the hardware works,” Dorante says. “If their code runs smoothly, the hardware will react and make the expression they want.”

These new results show that there are ways to make that new hardware roughly sink up to the transplant recipients internal emotional software. And, importantly, actual computer software may be one of the ways to push this idea forward.

Dorante and his colleagues suggest that computer software is good enough at recognizing emotions that it could be an “objective, noninvasive, and non-obtrusive” tool, that can allow people to get in some reps with their new faces.

What’s in a face

We don’t think twice about it, but we’re constantly reading emotional signals on other people’s faces. Facial recognition is intertwined with empathy. Facial expressions, even small ones, have been likened to an entire language of its own.

"We have to ask ourselves why people would undergo the risks of immunosuppression and experimental surgery?”

Face transplant recipient Patrick Hardison (who was not a part of this study) poses with his family and Dr. Eduardo Rodriguez. NYU Langone/Jay Brady

This paper emphasizes that the face itself allows entry an entirely non-verbal social world. And people undergoing facial transplants are learning to re-enter that world with a face that didn’t begin as their own, but often find that the risks of the procedure are worth it, says Dorante.

“These are relatively healthy people who could survive fine without a face transplant but who desire to be another face in the crowd and be able to be in society living the life they want to live,” Dorante says of the patients in this study.

He continues: “So we have to ask ourselves why people wound undergo the risks of immunosuppression and experimental surgery?”

The value of being able to fully express emotions, he hopes, will hopefully make a new face even more functional, and worth the complex procedure that’s required to get it fully installed.

“I hope that people just realize that there is more to a face than its many parts,” he says.

Partial Abstract:

Design, Setting and Participants: This single-center case-control study analyzed videos with commercially available video analysis software capable of detecting emotional expression. The study participants were 6 patients who underwent face transplant at Brigham and Women’s Hospital between April 2009 and March 2014. They were matched by age, race/ethnicity, culture, and sex to 6 healthy controls with no prior facial surgical procedures. Participants were asked to perform either emotional expressions (direct evaluation) or standardized facial movements (indirect evaluation). Videos were obtained in a clinical setting, except for direct evaluation videos of 3 patients that were recorded at the patients’ residences. Data analysis was performed from June 2018 to November 2018.

Main Outcomes and Measures: The possibility of detecting the emotional expressions of happiness, sadness, anger, fear, surprise, and disgust was evaluated using intensity score values between 0 and 1, representing expressions that are absent or fully present, respectively.

Results: Six patients underwent face transplant (4men; mean[SD] age,42 [14] years). Four underwent full face transplants, and 2 underwent partial face transplants of the middle and lower two-thirds of the face. In healthy controls, happiness was the only emotion reliably recognized in both indirect (mean [SD] intensity score, 0.92 [0.05]) and direct (mean [SD] intensity score, 0.91 [0.04]) evaluation. Indirect evaluation showed that expression of happiness significantly improved 1 year after transplant (0.04 point per year; 95% CI, 0.02 to 0.06 point per year; P = .002). Expression of happiness was restored to a mean of 43% (range, 14% to 75%) of that of healthy controls after face transplant. The expression of sadness showed a significant change only during the first year after transplant (−0.53 point per year; 95% CI, −0.82 to −0.24 point per year; P = .005). All other emotions were detectable with no significant change after transplant. Nearly all emotions were detectable in long-term direct evaluation of 3 patients, with expression of happiness restored to a mean of 26% (range, 5% to 59%) of that of healthy controls.

Conclusions and Relevance: Partial restoration of facial emotional expression is possible after face transplant. Video analysis software may provide useful clinical information and aid rehabilitation after face transplant.