There are numerous articles and proof that getting rewarded in games causes positive chemical reactions in the brain. Here are some interesting articles on the subject:
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| [[File:Skinnerbox.gif|x300px|link=http://www.mostdangerousgamedesign.com/2013/08/the-psychology-of-rewards-in-games.html]]| [[File:Theory-of-Gaming-Motivation.png|x300px|link=http://www.thinkfeelplay.com/theory-of-gaming-motivation/]]
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| [http://www.mostdangerousgamedesign.com/2013/08/the-psychology-of-rewards-in-games.html The Psychology of Rewards in Games]