Our brains have a group of neurological structures called the “reward system.” Essentially how it works is that our brain leads us to crave the things we need to survive (eat food, have sex, etc.,) and when we do that thing, our brain lets us feel pleasure.
Video games do a really good job of “hacking” your reward system. A lot of video games have something in them called a compulsion loop – you are faced with a challenge (kill monsters,) you get a reward (gold and loot,) which leads to anticipation (level up and get better gear,) which leads to another challenge (kill stronger monsters) and so on and so forth.
The mental rewards you get from video games are a lot easier than the mental rewards you get from studying. Your brain likes the easy dopamine from video games a lot more than it likes the delayed gratification of doing well on your exams.
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