Unlike physical exercise, mental workouts probably do not demand significantly more energy than usual. Believing we have drained our brains, however, may be enough to induce weariness
Between October and June they shuffle out of auditoriums, gymnasiums and classrooms, their eyes adjusting to the sunlight as their fingers fumble to awaken cell phones that have been silent for four consecutive hours. Some raise a hand to their foreheads, as though trying to rub away a headache. Others linger in front of the parking lot, unsure of what to do next. They are absolutely exhausted, but not because of any strenuous physical activity. Rather, these high school students have just taken the SAT. "I was fast asleep as soon as I got home," Ikra Ahmad told The Local, a New York Times blog, when she was interviewed for a story on "SAT hangover."
To read the full, original article click on this link: Does Thinking Really Hard Burn More Calories?: Scientific American
