Why concentrating for long periods makes us tired

Concentrating for long periods of time results in fatigue, which is the brain’s way of diverting us to other more leisurely activities so that it can resume its general functions. — Zuma Press/dpa

Concentrating for a long time usually makes us tired, even though we’re not engaging in physical activity.

Researchers have now found a possible reason for why that could be and how cognitive fatigue can influence decision-making.