Similar Games

One of the best examples of a Biofeedback game is Nevermind: A biofeedback horror adventure. Which was being made not just as a horror game with biofeedback gameplay, but also as a tool for mental health.
This game gets more difficult the more scared you get, so you must learn to control yourself in order to complete the game. It is basically a mental health tool to combat anxiety.


The Nevermind Gameplay Trailer! from Erin Reynolds on Vimeo.

Unfortunately it was a Kickstarter project that didn't quite make its money ($129,615 out of $250,000).

FEAR

There have been many horror games, but the two I'll highlight are the FEAR and Amnesia series of games, with their dark first-person look. The prototype will not look 100% like them.
However it gives an idea what the final game could look like.

Amnesia: The Dark Descent

There are a few brainwave based games mostly small and experimental such as 'Throw Trucks with your Mind!' and 'Mindball'.
Most seem to only use your Concentration levels as a way of interacting with the game and not your emotional levels like how fearful or stressed you are, the closed to this is the game 'Nevermind' which uses Biofeedback, but still even that does not use brainwaves.

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Nevermind Team. 2013. Nevermind: The Game. [ONLINE] Available at: http://www.nevermindgame.com. [Accessed 06 March 14].

Brain wave video games 'should be classified as medical devices' | Metro News. 2014. Brain wave video games 'should be classified as medical devices' | Metro News. [ONLINE] Available at: http://metro.co.uk/2013/06/24/brain-wave-video-games-should-be-classified-as-medical-devices-3854329/. [Accessed 13 March 2014].

Mind games: Using brain waves to play a video game - Los Angeles Times. 2014. Mind games: Using brain waves to play a video game - Los Angeles Times. [ONLINE] Available at: http://articles.latimes.com/2013/mar/08/business/la-fi-tn-mind-games-how-brain-waves-control-a-video-game-20130307. [Accessed 13 March 2014].