When overhead LED lights or digital screens emit bright blue light in the evening, the ipRGCs absorb these photons and immediately transmit high-frequency electrical signals down the retinohypothalamic tract directly into the suprachiasmatic nucleus (SCN)—the brain's central biological clock38. The SCN registers this light as daytime and subsequently sends an inhibitory signal to the pineal gland, forcefully applying the physiological brakes to the synthesis and release of endogenous melatonin (the hormone that signals biological darkness and initiates the sleep-wake transition)39. Because melatonin requires a gradual, rolling onset (often referred to as Dim Light Melatonin Onset, or DLMO), abruptly turning off the lights immediately before getting into bed is insufficient39. By aggressively dimming overhead lights and switching to low-lux, warm/red-toned light sources placed low to the ground exactly two hours prior to sleep, the ipRGCs remain dormant, lifting the inhibition on the pineal gland and allowing a robust, natural wave of melatonin to flood the cerebrospinal fluid, perfectly synchronizing sleep architecture39.