[Jane McGonigal, PhD is the author of the New York Times bestseller Reality is Broken: Why Games Make Us Better and How They Can Change the World (you can find an extract here). Her new book SuperBetter is the definitive guide to a decade’s worth of psychology, neuroscience and medical research on how games can help us get stronger, happier, healthier, and more resilient. You can find Jane on Twitter @avantgame.]

What if you were surrounded by people ready and willing to help you with any problem at any time? How much more could you accomplish? How much more ambitious could you be?

If you play games regularly, you already have this ability. You can turn almost anyone into a real-life ally -- even a stranger, even someone who thinks they don’t like you -- by playing a game together. Whether it’s Mario Kart, League of Legends, Dance Central, Clash of Clans or Exploding Kittens, every time you play a multiplayer game, you rewire your brain in ways that actually make it easier for you to get and to give help in everyday life.

This power -- the ability to get stronger social support when you need it most -- is one of the seven “gameful” abilities I explore in my new book SuperBetter. It’s a practical, science-based guide to using games to get happier, healthier and more resilient.

I’m excited to share this book with the Gamasutra community -- because I know that if you understand this science, it will help you make better games. More importantly, you’ll make games that help your players get better -- not just at exploring virtual worlds, shooting zombies, or solving puzzles, but also at overcoming real-life obstacles, becoming a better friend, and even controlling their thoughts and feelings so they can ward off anxiety and depression.

I hope you enjoy this excerpt from SuperBetter chapter two: “You’re surrounded by potential allies.”  -- Jane McGonigal (author of Reality is Broken)

In Hedgewars, players commandeer an army of pink hedgehogs for intergalactic space battle. (Think multi-player Angry Birds, but a bit more challenging -- and with flying spiny mammals instead of birds.) It’s simple to learn, playable on any computer or mobile phone -- and as researchers at the University of Helsinki recently discovered, it has a powerful effect on our bodies and brains.

When two people play Hedgewars together in the same room, they experience something that Dr. Michiel Sovijärvi-Spapé and Dr. Niklas Ravaja describe as “neurological and physiological linkage.” Or, in lay person’s terms, a mind-and-body meld. The two players start to make the same facial expressions, smiling and frowning in unison. Their heart rates adapt to the same rhythm. Their breathing patterns sync. Most astonishingly, their brain waves sync, as their neurons start to “mirror” each other -- a process that helps each of them anticipate what the other will do next. All these changes happen almost immediately, within minutes of starting to play.

Surprisingly, this synchronization occurs whether the two players are cooperating or competing with each other. It doesn’t matter whether you consider your fellow player a teammate or an opponent. When you play Hedgewars together, your minds and bodies start to operate in near-perfect harmony.

What makes these biological linkages so interesting to researchers? As psychologists have recently discovered, all four types of synchronization -- facial expression, heart rate, respiration, and neural activity -- are strongly correlated with increased empathy and social bonding. The more we sync up with someone, the more we like them -- and the more likely we are to help them in the future.

It’s not surprising, then, that in surveys conducted afterward, Hedgewars players do indeed report feeling high levels of empathy and connection with each other -- again, regardless of whether they played cooperatively or competitively.

Hedgewars, as it turns out, is not special in this regard. In fact, as an expanding field of research shows, any game played simultaneously by two people in the same physical location creates this same kind of “mind meld” and body synchronization -- laying the foundation for a more powerful and positive relationship after the game is over.

How do games trigger a mind-and-body connection so quickly and effectively -- and is there anything else you can do to achieve a similar effect? Let’s dig into the science of synchronization to find out.

The science of mind-body synchronization

Humans unconsciously mirror and imitate each other constantly. We fall into lockstep when walking together. We return someone’s smile naturally, without thinking. We shift our body language to match the posture of people we like. And it’s not just a one-on-one phenomenon. At sporting events and concerts, we make the same facial expressions and move in unison with other fans, creating entire crowds of biologically linked individuals.

Not all synchronization is visibly obvious. Research shows, for example, that a mother’s heartbeat synchronizes with her infant’s when she holds her. And when a close friend tells you a story about his day, you experience what scientists call neural coupling. Your brain activity mirrors your friend’s as closely as if it were your own experience he were describing. It’s quite amazing when you think about it: your brain processes your friend’s story as if what happened to him had actually happened to you.

Why are these spontaneous biological connections so common? Scientists argue that without them, survival -- let alone successful social interaction -- would be impossible. In order to interact with other people, we have to be able to understand them. What are they thinking? What are they feeling? What action are they about to take? Do they want to hurt you or help you? But it’s not easy to read someone else’s mind or guess what they’re feeling. In fact, the only way we can do it is by recreating their thoughts and feelings in our own minds and bodies.

Consider this example: A stranger is smiling at you. Does he mean you well, or does he mean you harm? You involuntarily smile back -- with the same kind of smile he just gave you. Your smile may be fleeting -- maybe it lasts just for a microsecond, barely detectable. But now your brain understands the stranger’s intentions. It knows whether the smile you just gave back is the kind of warm, genuine smile you typically give people you intend to be nice to, or a pained, insincere smile you give to people you don’t like. Only by becoming a mirror for someone else are you able to accurately deduce his intentions.

Here’s another example: You run to catch up to someone and start walking beside her. You naturally fall into lockstep, and in doing so, you get important information about her state of mind. Perhaps your stride feels slightly longer and faster than usual -- you physically start to feel her sense of urgency. Or perhaps you notice yourself relaxing, walking more slowly than usual. You start to feel the same sense of calm as your partner. By unconsciously mimicking her physical movement, you suddenly have access to her emotions!

We synchronize like this hundreds of times every day without thinking about it. People who do it more tend to score higher on measures of empathy and social intelligence. That’s because the more you mirror and mimic, the better you understand the people around you.

That just leaves one important question to answer: why do we like people better when we mimic and mirror them? It’s not just a matter of better understanding. Countless studies have shown that we become closer to, more affectionate toward, and more likely to help the people we sync up with. Why?

Scientists theorize that syncing up creates an “upward spiral” of positive connection between two people. It helps us understand each other better, which means we have smoother social interactions -- and that makes us more willing to interact with each other again in the future. When we’re biologically synced up, studies show, we also perform more effectively together, because we’re better able to anticipate each other’s actions. Experiencing success together makes us more likely to help each other in the future. Meanwhile we more naturally like people who we perceive to be like ourselves. So when we unconsciously notice someone else mirroring us, we start to feel more positively about them. And the more positively we feel about someone, the more time we tend to spend with them, giving us more opportunities to sync up and strengthen our bond.

Why gameplay synchronization is more powerful than any other kind

If synchronization happens all the time, what makes the syncing that takes place during game play so special?

In some regards, there’s nothing special about it -- it works exactly as synchronization works during any kind of social interaction. Because you and your fellow player are focusing your attention on the same activity at the same time, your neurons start to mirror each other. And because emotions are contagious, you will pass your emotions back and forth -- whether it’s pride in a successful move, or frustration over a difficult obstacle, or surprise at an unexpected outcome. As your feelings align, so do your bodies -- from the muscles in your face that express different feelings, to the amount of sweat on your skin that reveals how excited or stressed out you are.

All shared activities -- such as watching a movie, having a conversation, or listening to music -- have a similar potential to create mind-and-body links. However, the intensity of game-based linkage is typically much stronger, owing to the special kind of attention we give to games: when we play, we go into a state of deep focus, or flow. And when two people are in flow together, the synchronization is far greater (and far more enjoyable) than when they participate in less mentally absorbing activities. Likewise, because we tend to feel heightened emotions like excitement, pride and wonder during game play, the quality of emotional linkage is heightened as well. The stronger our synchronized feelings, the deeper our mind-and-body connection.

But what’s really special about syncing during game play is best explained by what psychologists call theory of mind, which is short for having an accurate theory of what’s going on in someone else’s mind. When you’re playing a game with someone else, you spend a tremendous amount of time trying to anticipate what they’re going to do next. This is true whether you’re playing cooperatively or competitively: the more you can accurately model what your coplayer is thinking, the more successful you’ll be in the game.

Game play requires a powerful theory of mind, much more so than ordinary social interactions. Compared with taking a walk together or having a conversation, game play -- with all its unpredictability and constant decision making -- demands much tighter and more sustained synchronization. It’s due to this high-demand social environment that neurological and physiological links happen so quickly and easily whenever we play. It’s simply the nature of the game.

Because synchronization happens so rapidly, reliably, and deeply during game play, many gamers find it particularly useful for creating stronger social bonds. This is especially true for introverted individuals, who seem to benefit greatly from the easy and powerful social connections afforded by games.

Real-world studies offer even more insight into the benefits of syncing up through game play. Research from Brigham Young University’s School of Family Life, for example, shows that playing video games together regularly in the same physical space increases the sense of connection between parent and child. And for children with autism, multiplayer video games have been shown to increase cooperation, improve family social interactions, and increase social intelligence. Children with autism communicate more directly and confidently with their peers and siblings after playing a game together. They also pay each other more compliments and engage more frequently in positive touching, such as giving each other high-fives.

The research is clear: If you want to strengthen your bond with someone, consider taking the time to play together more often in the same physical space. You’ll have a much stronger connection with that person, in body and in mind. And as an added benefit, your brain will become even better at syncing up with others -- making you a better potential ally to anyone, even people you don’t play games with.

What this science means for game developers

Synchronization (and the specific social benefits that come with it) only happens when we’re in the same physical space as other players. So consider making games that support co-located play -- whether it’s simultaneous play on a single device, turn-based, split-screen or multi-device. Think: the Worms games for iPads, the Mario Kart series, Lego Marvel Superheroes, Just Dance, Never Alone, board games like Pandemic, card games like Exploding Kittens, augmented reality games like Ingress, or the multi-phone mobile game Spaceteam. This is an important space that needs more experimentation and innovation-- there are so many possibilities for co-located play just waiting to be invented!

Of course, there are social benefits to online multiplayer games (like League of Legends) and asynchronous social gaming too (like Candy Crush Saga) -- just a different kind of benefit. Find out what they are, and how they can inspire your game design in… SuperBetter.