Our biological clock learns to anticipate our wake-up time and triggers a rise in cortisol just before the alarm goes off, allowing us to wake up naturally.

noli's read

This phenomenon of hormonal anticipation is scientifically well-documented, notably by a significant experimental study published in the journal Nature (Born et al., 1999). This research demonstrated that individuals expecting to be awakened at a specific time showed a progressive increase in preparatory hormones in the hour preceding awakening, compared to those awakened by surprise. Our internal clock, orchestrated by the suprachiasmatic nucleus, effectively synchronizes this transition by increasing cortisol and decreasing melatonin to wake us up gently. However, the specific 'four-day' rule for programming this anticipation is a simplification by the creator; chronobiology research shows that the speed of our rhythm's adjustment varies greatly depending on the regularity of our bedtime and our chronotype. Furthermore, this spontaneous awakening depends heavily on other factors such as exposure to daylight, and not solely on learning the alarm time. In short, the concept of hormonal anticipation is very solid, even if the transition to a natural awakening involves overall regularity rather than simple mechanical training.

the sources

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