The science of fear: How to measure scares in gaming

From the lackluster scares of Resident Evil 5 to looping dread of P.T., fluctuations in the quality of horror games have made the genre a notoriously unreliable venture. But what if you could ensure your video game would feature genuine scares?

As part of a preliminary push toward finding an answer to this question, British game studio Supermassive Games is experimenting with technology originally used to measure stress levels in children with epilepsy. Throughout the development of Until Dawn, the studio's first step into the horror genre, the game developer is using electrodermal sensors to test the effectiveness of its scares.

Can you measure fear?

"We can only really tell whether we're achieving what we set out to achieve when we put it in the hands of players for their first time," Supermassive Games' managing director Pete Samuels tells us. Until Dawn, originally announced in 2012 for PlayStation 3, has since experienced enormous changes during development. While the studio first planned to pair the game with the PlayStation Move controller, major steps have since been made to take the horror homage to the new-gen PlayStation 4 instead. Alongside these changes, the studio is now focusing on using new technology to test what fear looks like in modern gamers.

"It's not a new problem for developers though," Samuels said. "Testing our work throughout development on hundreds people that have an interest in the type of game we're making and then analysing their first-time-experience is an essential part of the development process. We set up these test environments slightly differently in order to test specific aspects of the game. For testing fear and fright, we use what we refer to as the ‘fear machine', which has the player wired to a device that detects skin response.

"Galvanic Skin Response Testing, picks up the immediate change in moisture content of the skin at times of heightened emotion. It's not something that a person can directly control, so we can trust the results as ‘honest'. As a subject plays the game this scientific equipment plots the response levels on a graph so that we can see, in real-time, whether the techniques we've used to drive emotional responses such as fear and fright have worked. By analysing the results from hundreds of candidates we can determine how well we've achieved that for the majority of people. If the test results suggest that something doesn't work in the way we expected or wanted, we revisit it, re-design it, change it and test it again, and we repeat this process until we get the results that we want."

Fight or flight

This electrodermal tech was developed by the Massachusetts Institute of Technology's Media Lab under a simple premise, a representative at MIT Media Lab project's Affectiva tells us.

When a person experiences stress, moisture collects under their skin as part of a response from their nervous system. The rise in moisture causes skin to become more electrically conductive. These "skin conductance" sensors will send out a small electrical pulse to an area of the skin and measure the strength of this signal compared to another area of skin in order to test the conductivity. Whether this is used to measure stress in sufferers of epilepsy or not, she tells us, the fight or flight response remains the same.

Sensors like this have been in use for over a year in trial studies that aim to create a measurement of psychological pain in patients where diagnosis can be difficult. The device is also being used to measure the efficacy of medication in sufferers of Rett Syndrome, a genetic neurological disorder that causes loss of speech and other impaired cognitive functions.

Sony, the publisher for Until Dawn, has previously tested the waters of these electrodermal testing methods. During early development of the PlayStation 4 hardware, the company went through a number of different models for the DualShock 4 controller, including one that sensed players' stress through sweaty hands, lead architect Mark Cerny previously confirmed.

The technology of fear

According to Cerny, Sony tested gamepads that could detect players' galvanic skin response — that is, the conductivity of players' skin, which can indicate increased stress based on how sweaty their palms are.

"We had a long research project where we looked at pretty much any idea we could think of," Cerny said at the time. "Would it help to measure the galvanic response of the skin? We tried out a tremendous number of things — and then we went to the game teams to ask them what they thought they could use from the controller."

But the technology is imperfect, an Affectiva representative tells us, particularly due to external factors like temperature and humidity that can affect measurements and lead to inconsistent results. Likewise, internal factors including use of medications can also have an affect on measurements. And despite an increased interest in biometric testing, some developers seek alternate routes.

"There are companies using biometric testing to eke every last scream out of players," Amnesia: A Machine for Pigs lead designer Andrew Crawshaw tells us, "and ultimately you need the feedback of an audience to let you know if a game is scary or not."

Crawshaw maintains that this kind of testing is particularly useful for measuring the effectiveness of a very particular kind of scare, however.

What kinds of fear can be measured?

"I think that kind of player feedback would be useful for measuring the effectiveness of those basic, visceral responses. They're like the 'sugar hits' of horror games.

"With AAMFP we wanted to work on a more cerebral level; we wanted it to leave an unease in the player's mind, and not just a funny stain in their pants. But it's really easy to develop blind spots when making a game. You have to rely on your hunches, and remember your initial experiences with parts of the game, and combine them with periodic reviews from fresh eyes. There are periods in a game's development when doubt creeps in — but that's no different from any other creative process."

This studio's methods differ, focusing mainly on the development of its atmospheric story to "create an overall air of unease," Crawshaw continues.

"Once we knew that people felt uneasy with the storyline we were on solid ground, and we could focus on using aural and visual tricks to support (and exploit) that unease. When it came to more visceral scares, there are lots of cheap tricks you can use to frighten people and making people jump isn't all that hard. If you've created the right mood for people to be scared shitless, they end up being willing 'victims'. Once you've defined the journey you want to take you player on, defining the beats becomes easier."

A new type of horror

However, Supermassive creative director Will Byles maintains the creation of fear in video games requires methods that wouldn't be necessary in other, more traditional storytelling media.

"The fundamental difference between film and game is the obvious one of passive observation versus active interaction," Byles tells us. "A movie, no matter how good, can only be observed and as such the emotion that you as a member of the audience can feel can only be at best empathic. That is not to belittle it at all and a skilled filmmaker can create a suspension of disbelief that transports the viewer into narrative, but there is nothing you can do to affect the outcome or fate of the characters.

"Games have the opposite starting point but are faced with other challenges. The emotion that you can feel as a player, rather than a viewer, is in the first person. It is your fear that you are feeling, rather than characters fear with which you are empathising. First person emotion is much stronger than third, which can help to quickly build a sense of fear."

Challenges, says Supermassive's Byles, come in part from technological difficulties in creating a suspension of disbelief that works for an extremely sophisticated movie-going audience. In other words, if characters, sets, lighting and performances aren't believable, than the absence of suspension of disbelief can leave the player unengaged. "In that sense," he tells us, "the techniques used to suspend a player's disbelief must be more sophisticated to be effective."

Affectiva maintains the science speaks for itself as fear materializes in the same physical responses regardless of the trigger. Electrodermal activity allows for electrical changes at the surface of the skin to be measured when the skin receives innervating signals from the brain. For most people, this will happen in response to emotional arousal, increased cognitive workload or physical exertion, as your brain sends signals to the skin to increase the level of sweating. "You may not feel any sweat on the surface of the skin," reads a statement from the technology group, "but the electrical conductance increases in a measurably significant way as the pores begin to fill below the surface.

'People are different. They fear different things and different emotions are triggered by different things. Human emotion is very complex'

"I'm confident that Until Dawn will be a terrifying experience for most people, but it's extremely difficult to make something that is scary for absolutely everyone and in all situations," says Samuels. "People are different. They fear different things and different emotions are triggered by different things. Human emotion is very complex. We've been working on a feature that recognises and uses this within the story which is being implemented now and further personalises the Until Dawn story to the player in a way that plays on their own personal fears. I can't say much more about that right now but we're excited about seeing how effective this will be when we test it."