Fear (voice of Bill Hader), Sadness (voice of Phyllis Smith), Joy (voice of Amy Poehler), Disgust (voice of Mindy Kaling) and Anger (voice of Lewis Black) guide 11-year-old Riley from Headquarters, the control center inside her mind. ©2014 Disney•Pixar. All Rights Reserved. Credit: Disney/Pixar

As people get older, their emotions get more complex. Joyful memories of childhood become tinged with loss and nostalgia. The recognition that life is short and goes by fast introduces a sorrowful note into even our happiest moments, as we remember that they are going to end. But even so, you may find that a little sadness actually deepens your appreciation for and experience of joy. 

Pixar, the animation studio owned by Disney, is famous for crafting movies that capture that complex mix of emotions. Think about the heart-rending scene in "Up," in which a couple’s loving marriage passes by in a minute, Wall-E’s wordless comedy in a post-apocalyptic landscape, or the deep nostalgia of the toys in "Toy Story" remembering the happy days when they were played with.

The animated movie of the summer, "Inside Out," does more than capture these emotions -- its plot actually revolves around them. The film's main characters are the emotions in a little girl's brain, and the storyline focuses on how to recover joy after a traumatic experience.

This idea is one that the adults in the audience will relate to better than the kids they are accompanying. Scientific studies suggest that, compared with younger people, older people are much more likely to experience seemingly contradictory emotions at the same time. As people age and near the end of their life, they experience more moments of poignancy -- happy moments that also tinged with sadness, because of an awareness that the happy moment will end. These same studies show that, in addition to having more mixed emotions, older people are generally happier and more emotionally stable than younger people.

One of the main lessons of "Inside Out" is about how contradictory emotions can work in concert. The movie centers on an 11-year-old girl named Riley, whose life goes through big changes when her family moves from Minnesota to San Francisco. "Inside Out" is mostly set inside Riley’s mind, where five core emotions of Joy, Sadness, Disgust, Fear and Anger – each imagined as a tiny person and voiced by a famous comedian – manage the brain’s control center.


Disney•Pixar's "Inside Out" takes us to the most extraordinary location yet - inside the mind of Riley. (Disney/Pixar)

Riley’s childhood has been a happy one: Most of her memories have been joyful, represented as gold-colored spheres, and Joy (played by Amy Poehler) is firmly in command of the brain’s control room. But with the stress and disruption of the move, Riley’s emotions and memories start to change in unforeseen ways. Some of her joyful, golden memories gradually become tinged blue with sadness, as she undergoes the experience of loss, and recalls her happy life in Minnesota from afar.

The movie imagines the brain like a giant pin ball machine in which memories, represented as brightly colored balls of light, are created, shot far off into the distance to be stored in long-term memory, and sometimes recalled to the control room for Riley’s viewing pleasure.

The film may not give the most accurate representation of the mechanics of the brain, but, as numerous scientists and commentators have argued, it does a pretty good job of describing our emotional development. At roughly Riley’s age, kids begin to experience the loss of childhood. In the words of its director, the movie’s beautiful message to kids is that it’s difficult to grow up, and it’s okay to be sad about it.

[What ‘Inside Out,’ a film about feelings, gets right about the brain]

When we have mixed happy and sad emotions about the past, we often call that “nostalgia.” Riley experiences nostalgia when she leaves behind the childhood she loves in Minnesota, and her happy childhood memories become tinged with sadness.

But people can also have mixed emotions when they experience the present and think about the future. One study by Stanford psychologist Laura Carstensen, which Atul Gawande, a surgeon and writer, cites in his book "Being Mortal," refers to this feeling as “poignancy” – the sadness that accompanies a joyful experience, because you know that happy moment is going to end.

Carstensen's work demonstrates that older people are much more likely to experience feelings of poignancy. “Recent research has shown that in everyday life, older people experience mixed emotions, such as happiness and sadness, more so than their younger counterparts and that this co-occurrence of positive and negative emotion becomes more frequent with age,” one study says.

The researchers believe poignancy occurs because of a sense of shifting time horizons. The knowledge that happy moments could end soon makes us sad, but also heightens our appreciation for it. For older people, poignancy is definitely linked with a deeper understanding of mortality, which can tinge positive everyday events with mixed emotions. The research also shows that the feeling is more common among people who are terminally ill, or younger people who are aware of big life changes approaching, such as a move or a graduation.

Carstensen, a founding director of the Stanford Center of Longevity, came to this area of research because of a near-death experience she had when she was young. As Gawande writes in "Being Mortal," Carstensen almost died in a car crash in 1974, when she was 21. The car rolled over an embankment, and she was left in the hospital bed for months with a serious head injury, internal bleeding, shattered bones, and plenty of time to think about her own mortality.

“I got better enough to realize how close I had come to losing my life, and I saw very differently what mattered to me. What mattered were other people in my life,” she told Gawande in "Being Mortal."

Carstensen’s work has showed that older people, in addition to having mixed emotions, are generally happier than younger people. In one study, she analyzed the emotional experiences of nearly 200 people for many years, paging them randomly 35 times a week and asking them to record the emotion they were feeling at the moment. The study found that older people were less prone to anxiety, depression and anger. They found living to be a more emotionally satisfying and stable experience as time passed, even as they had more moments of positive and negative emotion mixed together.


Italian director and actor Roberto Beligni, left, kisses Italian actress Nicoletta Braschi in the movie 'Life Is Beautiful'. (AP Photo/Sergio Strizzi)

Studies on poignancy have found that the feeling can be triggered by thinking about your own mortality, or by considering a big life change. Interestingly enough, the feeling can also be brought on by watching certain movies. In one study from 2001, researchers inculcated feelings of poignancy in their subjects by showing them the 1997 movie "Life Is Beautiful."

In fact, poignancy may be why Pixar movies are popular with adults as with kids. The makers of "Inside Out" throw in a few jokes just for the adults: For example, a reference to San Francisco's male "bears." But adults are also drawn to Pixar's animated films because, unlike many saccharine cartoons, they hit a variety of emotional notes at the same time -- pulling at our heartstrings in order to bring us an even deeper joy.


Still from the movie, "Up" (2009). Disney / Pixar

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