study had 210 subjects and gathered information by having them fill out "time-use diaries."
The study says that students who had a roommate bring a game console to school showed a substantial drop in time spent studying. These students did "not exhibit different levels of class attendance, partying, study efficiency or paid employment - all factors that also could affect grades ... This means that the lower grades of students whose roommates brought video games can be attributed to the fact that these students studied less." The simple lesson to walk away from this is that if you're going to play video games, make sure it doesn't affect your study time. That's it, lesson learned.