Executive Friction begins at the environmental layer — the gains that accrue while you do nothing. Three sub-systems carry the strongest evidence: circadian lighting (bright, cool morning light and dim, warm evening light entrains the sleep-wake clock); thermal sleep regulation (active cooling shortens sleep onset and supports deep sleep for many); and air quality (elevated indoor CO₂ measurably degrades cognitive-function scores — ventilation and HEPA filtration protect focus).

The habitat does the work while you sleep and think. Correct light timing repairs sleep onset; sub-1000 ppm air preserves afternoon cognition; a cool bed buys deep-sleep minutes — all passively, every night.
Circadian and air-quality effects are well-supported; thermal response is individual. Devices are optimization tools, not therapy.