Thinking takes real effort. It requires sustained attention. Scientists have known for some time that focusing your mind consumes considerable metabolic resources. But in our day-to-day lives, we discount the effort needed to pay attention and think because it doesn’t feel as physically strenuous as, say, lifting a 50-pound weight.
Next time you’re in your classroom and the students are struggling with a task, maybe you’ll want to think of this study. In it, participants would rather get zapped with an electric heater instead of completing an intense mental task.