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Many people assume that productivity depends mainly on willpower, yet researchers studying attention have found that the first few hours after waking often provide a physiological advantage for focused work, independent of how motivated a person feels. During this window, levels of a stress-related hormone that sharpens alertness are naturally elevated, and the brain has not yet accumulated the mental fatigue caused by decision-making throughout the day. This helps explain why many people report that tasks requiring deep concentration feel easier in the morning, even without deliberate effort to avoid distractions. However, the researchers caution that this advantage varies significantly between individuals, since some people's internal body clocks are naturally shifted later, meaning their optimal focus window may occur closer to midday or even evening rather than immediately after waking.