This website uses cookies to store information on your computer. Some of these cookies are used for visitor analysis, others are essential to making our site function properly and improve the user experience. By using this site, you consent to the placement of these cookies. Click Accept to consent and dismiss this message or Deny to leave this website. Read our Privacy Statement for more.
Eye on Psi Chi: Winter 2016


Eye on Psi Chi

Spring 2016 | Volume 20 | Issue 3


Image copyright 2016 by Pixar Animation Studios. Printed with permission.

Inside Out:Behind-the-Scenes Science With Dacher Keltner, PhD

Bradley Cannon, Psi Chi Writer

View this issue in Digital and PDF formats.

Six years ago, Pete Docter (the director of Pixar’s Monsters, Inc and Up) made a phone call to explain his ideas for a film about how emotions shape people’s interior lives and relationships with others. On the other end of the call was Dacher Keltner, PhD, an emotion psychologist at the University of California, Berkeley. Dr. Keltner agreed that these would be great topics for a movie and became a major consultant throughout the development of Pixar’s Inside Out. Today, he discusses his interactions with Pixar, as well as some of the scientific thought that went into this highly successful and well-liked 2015 film.

In his own words, Dr. Keltner says, “What I mainly did at Pixar was to serve as a scientific sounding board for their core interests such as how people remember emotions and how our current emotions shape our recollection of the past.” In addition to many e-mails and phone calls, he estimates that he visited Pixar Studios at least five or six times to speak with small groups of three to seven. These groups included people such as Docter; Doctor’s right-hand man, Ronnie del Carmen; and some of the film’s animators. “Sometimes,” he explains, “I would talk about the science of emotional expression or neurophysiology of emotion. Then, most of the time, I would really just answer questions and have conversations.”

How Scientifically Accurate Is Inside Out?

In the film, an 11-year-old girl named Riley struggles to adapt when she and her parents move from Minnesota to San Francisco. To help her through this difficult transition, Riley is guided by five emotions living in her head—Joy, Sadness, Anger, Fear, and Disgust, each of whom have very different ideas about how to handle the many challenges ahead. As Dr. Keltner has said many times about the movie, “I think they really nailed it” (Hamilton & Ulaby, 2015, para. 4). Today, he elaborates by recounting how astounded he was at Docter’s “curiosity and careful treatment of the science.” Describing just one of many e-mail exchanges, he says, “After the film came out, Pete told me that he was about to speak with a Russian neuroscientist about the film. He had all of these questions for me about dopamine, the opioids, oxytocin, and the neural chemistry of emotion. I sent him a bunch of stuff, and then he asked some really deep follow-up questions. That typified my experiences with him. He was really focused on wonderful conversations about emotion science.”

According to Dr. Keltner, “The influence of the science of emotion is used in a lot of places in the film.” A few examples include the way that emotions can change memories over time, that emotions guide human perceptions of the world, and that all emotions—both positive and negative—are important to create healthy individuals (Judd, 2015; Keltner & Ekman, 2015). For another example of science used in the film, Dr. Keltner says he studies something called vocal bursts, which are little universal sounds that people make to express emotions. Pieces of these vocal bursts are used in the movie, in particular when Riley reunites with her mom and dad near the conclusion.

Of course, not everything in the film is scientifically accurate. For instance, to create a more viewer-friendly film, the number of emotion characters was reduced to only five. Also, Riley’s brain is missing any sort of conscious control mechanism to regulate her emotions. However, Docter and his team spoke with Dr. Keltner about making changes of this sort often. They explained that they appreciated the information he gave them, but they also reminded him that they were artists paid to create a film. Thus, they would sometimes have to deviate from the science.

About this, Dr. Keltner is quick to express his acceptance of their decisions, and he reminds readers that “these were all simply tensions that the filmmakers had to deal with.” Rather than letting small inaccuracies distract him, he instead appreciates the awareness that the film has brought to emotion science. He also embraces the many discussions about emotions that have stemmed from the film and its artistic choices.

The Purpose of Sadness

Perhaps the part of the film that Dr. Keltner had the most tangible influence on was in the character, Sadness. About this, he says, “I distinctly remember Pete reaching out to me about two and a half years into the film’s development to ask me about sadness.”

He asked questions such as

  • “What is sadness?”
  • “Why do we have it?”
  • “Does it do us any good?” and
  • “What is its evolutionary function?”

In response, Dr. Keltner told him about sadness being “a necessary part of development, a catalyst of change, and a way of uniting people.” It is likely that the prominence of Sadness in the film, which he thinks is one of the really exciting parts to it, came out of the conversation in part.

He says, “There was kind of a key moment, as is often the case with Pixar films because they tend to go through five years of development, take a lot of creative talent, and often hit roadblocks or points of critical decision. Very interestingly, when Joy gets lost, they were originally going to have Anxiety or Fear accompany her, but Pete really wanted it to be Sadness so that he could delve into the themes of joy and sadness, and the purpose of sadness in a young girl’s mind. The executive staff was skeptical and worried that the movie would be too melancholy. Pete had to really fight for that, and I think it was a triumph and the critical artistic decision in the film.”

Six “What If” Questions to Consider
  1. What if Riley had been a boy?
  2. “We talked a lot about this,” Dr. Keltner exclaims. “When girls reach the preteen years, their positive emotions plummet, and when they become teenagers, a gender difference in sadness and depression really hits. This is shown in the work of the late Susan Nolen Hoeksema, which is really compelling work about how girl teenagers are twice as vulnerable to depression as boys. I think that is one reason why the sadness was so poignant in the film.” “What you would have to do if Riley was a boy,” he continues, “is make the story a little more about anger and a little more about getting into a different kind of trouble. For example, instead of retreating into himself, the boy might be bumping into other kids or doing something that breaks the law such as stealing. In that case, I think anger would have played a more prominent role.”

  3. What if Riley had lived in another culture?
  4. One of Dr. Keltner’s many interests is in how emotions vary in different cultures. To provide an example of an alternate view than the Western view presented in the film, he says, “Let’s say that you were to tell this story in Japan. What we know from the work of people like Shinobu Kitayama and Yukiko Uchida is that joy would not have been so hyperactive and so agentic. The positive state in Riley’s mind would have been oriented toward social harmony rather than self-assertion, and that would make for a very different movie. If it took place in Japan, I really would have made a strong case that embarrassment would need to be a character because Japan has a more respectful- and modesty-oriented culture. As another example, there are cultures like some Alaskan indigenous people who just don’t feel anger. It isn’t so prominent in how they react to a situation, so that might have involved a Riley without Anger.”

  5. What if you could change the characters to make them more scientifically accurate?
  6. “Pete e-mailed and called me a lot to say things like, ‘Hey, tell me the latest about dopamine and the vagus nerve,’ or ‘What happens to a girl’s emotions when she is 11?’ and I would pass on things we have learned from the science. After the first screening of the film, he asked me, ‘How would you change the emotions?’ One of the things that I felt was that disgust is very intense like the social disgust people feel toward others who they disapprove of. I felt that the Disgust character was really great, but I suggested that they could intensify that if they wanted to be really true to the science. Otherwise, I felt like the characters were interesting and close to what I would have portrayed them as in the Pixar vein.”

  7. What if the emotion characters were different sexes?
  8. Dr. Keltner laughs. “If you were to be entirely truthful to the science, emotions obviously wouldn’t have human forms. They would have chemical structural forms, so they wouldn’t be gendered or have mustaches. They would be multigender entities. Men do tend to get a little angrier than women, so it is maybe a little justified to make Anger a man in Riley’s head. Studies also show that women tend to cry a little more, so it is maybe okay to make Sadness a woman. But if you wanted to be totally scientifically accurate, you would do it differently with respect to gender.”

  9. What if Riley’s parents’ emotions had been different sexes?
  10. Dr. Keltner says that he never spoke to anyone at Pixar about that, but he guesses that they probably made all of Riley’s mother’s emotions women and her father’s emotions men because they recognized that there would be six-year-old kids watching the film. As Dr. Keltner explains, “Certain kinds of complexities, like the idea that you are inside a person’s head, are tough for a six-year-old to handle, so they probably wanted to keep it really simple artistically. I think that they probably made the gender decision for that reason.”

    “Also, I can’t remember if I talked about it with them, but I find that I personally felt very multigender when I was a young 20-year-old, as did my girlfriend. However, when people have kids, they kind of bear down into a more homogenized arrangement. Most moms and dads are overworked raising their kids and feel a little more gendered and a little bit more like moms and dads, so I think that might also have been a part of their thinking.”

  11. What if there had been a character named Awe?
  12. A large part of Dr. Keltner’s career has been built upon his research of the emotion, Awe. He says, “During my first meeting with Docter, I pitched Awe and all of these other emotions.” Ultimately, Awe, Embarrassment, Compassion, Surprise, and many others emotion characters were not used in the film. However, the thought of what any of those characters might have been like is certainly intriguing.

    “As for, Awe,” Dr. Keltner says, “the preteen years would be an okay time to portray this character, but not as good as it would be to show Awe in a sequel where Riley is 18. That would be the best age because of, for example, the abundance of rock and roll music, great ideas in college, nature, backpacking, and so forth. If Awe had been a part of Riley’s experience, I think it would have been tremendous because there could have been a moment where she listens to music or visits the Grand Canyon when her identity suddenly opens up and changes. I think that would have been aesthetically spectacular, but of course, they didn’t do it.”

Public Impact

Dr. Keltner has been truly blown away by how powerful the response has been to the film. Since it was released in June, he gets about two e-mails a day on average from people who saw that he was involved because of his name in the credits, on the film’s Wikipedia page, or because they heard so in an interview. According to Dr. Keltner, they usually contact him to say something like, “I teach Inside Out in a high school literature class and talk about how it conveys emotion.” Other times, they may say, “My daughter experienced early trauma, and she has seen the film six times. It gave her this insight into sadness that really changed her life.” Dr. Keltner pauses to let this sink in before continuing. “To have a sense that there is any kind of cultural experience that can change a child’s life is powerful. I have also had middle-aged dads tell me that, after seeing the film, they now understand their daughters and know how to relate to their daughters. I have had wives tell me that, when their husband saw it, the husband suddenly became more accessible. I had a mom e-mail me to say that she has a son who has Asperger’s who could never communicate about his emotions until he saw the film.”

Looking Outside of Inside Out

To anyone interested in learning more about emotions, Dr. Keltner says that you can expect to see a rich statement in the future about how emotion science is improving social media such as Facebook and Twitter. He also has high hopes that there might one day be another Inside Out movie in 10 or so years where Riley is 18 years old. In the meantime, many other articles about the science of the film are available online. Be sure to check these out, and then don’t stop there. Look outside of the film too, by continuing to reflect on and talk about the variety of emotions you encounter in your everyday life.


Hamilton, J., & Ulaby, N. (2015, June 15). The science of sadness and joy: ‘Inside Out’ gets childhood emotions right. Retrieved from

Judd, J. W. (2015). A conversation with the psychologist behind ‘Inside Out.’ Retrieved from

Keltner, D., & Ekman, P. (2015, July 3). The science of ‘Inside Out.’ The New York Times. Retrieved from

1Learn more about Dr. Keltner's research on the emotion awe in Cannon, B. (2014, Spring/Summer). Understanding the sensation of awe (without spoiling it) with Dacher Keltner, PhD. Eye on Psi Chi, 18(3). Retrieved from

Image from Rivera, J. (Producer), & Docter, P. (Director). Inside Out [film]. Copyright 2016 by Pixar Animation Studios. Printed with permission.

Dacher Keltner, PhD, is a full professor at the University of California, Berkeley and director of the Berkeley Social Interaction Lab ( and faculty director of the Greater Good Science Center ( Dr. Keltner’s research focuses on the biological and evolutionary origins of compassion, awe, love, and beauty, emotional expression, power, social class, and inequality. He is the coauthor of two textbooks, as well as the best-selling Born to Be Good: The Science of a Meaningful Life, and The Compassionate Instinct. His next book, The Power Paradox: How We Gain and Lose Influence,will be released in May with Penguin Press. Dr. Keltner has published more than 190 scientific articles. He has written for the New York Times Magazine, The Wall Street Journal, The London Times, and Utne Reader, and has received numerous national prizes and grants for his research. He served as a consultant for Pixar’s Inside Out and has worked at Facebook and Google on emotion-related projects. WIRED magazine recently rated Dr. Keltner’s podcasts from his course Emotion as one of the five best educational downloads, and the Utne Reader selected him for one of its fifty 2008 visionaries.

Copyright 2016 (Vol. 20, Iss. 3) Psi Chi, the International Honor Society in Psychology

Want More?

Watch a video of Dr. Keltner's 2016 Psi Chi Distinguished Lecture at WPA about "The Science of Inside Out"



Psi Chi Central Office
651 East 4th Street, Suite 600
Chattanooga, TN 37403

Phone: 423.756.2044 | Fax: 423.265.1529


Certified member of the
Association of College Honor Societies