"Why are we interested in emotion in games?" asked PhD-equipped game researcher Dr. Clive Chandler during a wide-ranging GDC Canada talk about the role and consequences of emotion in games. "As yet, games have not matched the sense of engagement displayed by the movie industry," said Chandler, who has also been a trained Baptist minister and children's entertainer. "We want to grab the hearts and minds." Chandler described a "Game Turing Test," a modification of Alan Turing's well-known eponymous test -- if you can't tell whether you're playing against a bot or another player, the game has passed the Game Turing Test. "What we need to do is understand human beings," said Chandler. "What are our perceptions? What are our belief systems?" "Your role is to use psychology in design to bolster our belief system, to get players excited and buy into it." The problem with this, he admitted, is that, "psychology was invented in order to confuse the mortal man. It takes four degrees to even understand what psychology is, let alone how to do it." As a quick summary, Chandler explained that while all humans share the experience of interpreting the world through their sensory perceptions, those perceptions can be fooled. To demonstrate this, he cycled through a number of optical illusions relying on the brain's ability to take visual leaps, then had the audience create the auditory effect of rain through a number of simultaneous hand noises. In addition to perception, there is emotion theory. "There are events, which cause some kind of arounsal, whatever that may be, which causes some kind of action, whatever that may be," Chandler explained -- but psychologists don't agree on which comes first. Presentation In 2003, research found that interviewers had different biases against interviewees with different accents, even with identical qualifications and experience. BT also found that customers were most likely to trust representatives with a Scottish accent. "If an NPC looks like a ruffian and has an accent of a ruffian, they are perceived as less trustworthy," says Chandler. He explained that the feeling of belief is achieved when the emotions of acceptance and trust are developed. Partly: "Designers need to design for trust," he advised. "We develop trust in our own characters' abilities and any NPCs we encounter in a number of ways...Similarly, you can foster distrust -- the NPC ignores you, goes off and does their own things." But there is also trust in ourselves as players. "If our character dies the first time we run into an orc, we don't really trust our abilities. But if that character actually beats a boss, we turn around and start believing in our abilities." "We can design scenarios, as designer, to bolster belief in our own characters as well as those of the NPCs we encounter -- but we can also fracture that belief." Fun or Fear Factors "Fun" can be defined as "a source of enjoyment," as by Raph Koster, Chandler noted, but there is no universal definition. Some "fun factors" include teamwork, competition, feeling like a superhero, bartering and trading, and so on. But "all fun and no substance is as bad as all challenge and no fun," he warned; that's "like a roller coaster with all ups and no spine-thrilling downs. "The name of the game is balance." The counter is fear, which can cause physiological responses due to the "fight or flight" impulse. Many people love that sensation: "Look at the prevalence of the horror movie; it's everywhere. Look at horror games." "Surely there's no harm in that? Well, actually, there is," said Chandler: Scientists have recently determined that after sustained fear, bodies stop producing adrenaline and being producing cortisol, which begins to break down non-essential organs and tissues to feed vital organs, increasing pain, promoting heart disease, high blood pressure, diabetes, and obesity. While adrenalin suspends digestion and dissipates after resolution and exercise, cortisol does not. But as of this year, scientists have apparently determined that there is another anti-stress hormone that potentially counteracts the effects of cortisol. It induces emotional bonding like hugging and kissing, as well as "basic feelings of comfort, security, and love." Metrics "But unless we have some way to measure the effect of these [emotions], how are we going to know what to do with it?" asked Chandler. Emotions result in physiological responses, and we can measure physiological responses, but it is difficult to match specific responses to specific emotions. However, in games, since developers create specific situations, it becomes easier to match stimuli with emotions. At Staffordshire University, Chandler and others are attempting to develop a "fear index" that determines a cortisol threshold measurement and links it to physiological respons. Essentially, "don't prolong fear," Chandler recommended. Include "cute, cuddly bits" after frightening parts to keep the roller coaster-like alternation. Conclusions "Human emotions are powerful. We need to be careful to produce an enjoyable roller coaster," concluded Chandler. "Cortisol can kill, and I don't think we want to be in the business of being sued because our games kill through fear. And I have to say, we're getting there, and we have to stop before we get there."