A recent study of college students found that they consumed more food after working on hard test problems than after a bout of running on a treadmill. Study authors suggest that this means that using intense brain power may trigger hunger more than physical exercise. You can learn more about the study here. 

Of course, this study used only a small cohort of students–38–and they were all college students in a lab setting. The lead researcher noted that time of day, testing lunch instead of dinner, and comparing different exercise types may yield different results. Still, it’s an interesting first foray into the study of how using your brain may make you hungry.