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Cognitive scientists studying attention have grown increasingly interested in the first ninety minutes after waking, a window some researchers term the 'cognitive prime.' During this period, cortisol levels rise sharply, sharpening alertness before the day's decisions and distractions accumulate. Studies tracking knowledge workers found that tasks requiring sustained analytical focus, such as drafting reports or debugging code, were completed markedly faster when attempted in this window rather than in the afternoon. Interestingly, the benefit was not simply a matter of fewer interruptions; even in controlled, distraction-free environments, morning performance surpassed afternoon performance on the same task type. Researchers caution, however, that the effect diminishes for people with certain sleep disorders or irregular shift patterns, whose cortisol rhythms are disrupted, suggesting the advantage stems from a biological rhythm rather than merely from a quieter morning schedule.