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How sleepiness is measured
Sleepiness still has no roadside test. But science is learning to measure it - in the clinic and in the body's biochemistry.
How sleepiness is measured
Sleepiness still has no roadside test. But science is learning to measure it - in the clinic and in the body's biochemistry.
MSLT and MWT
How quickly you fall asleep, and how long you can stay awake. Sleep centre tests, EOC.
IRM Zurich study
Looking for a direct signal of sleepiness in a biochemical sample. The path below.
The problem
Sleepiness has no breathalyser. Unlike alcohol, it leaves no measurable trace at an accident scene.
The three conditions
Twenty volunteers, in random order, compared across three states: eight hours of sleep (control), six hours for four nights (restriction), one night awake (total deprivation).
The method
Saliva is analysed by mass spectrometry. A machine learning model looks for the patterns that separate the conditions.
The result
Acute deprivation leaves a recognisable metabolic fingerprint: about twelve molecular features, clearest in the morning.
The limits
It is a proof of concept. The sample is small and homogeneous, twenty young men. It must be validated in real driving conditions.
The direction
A step toward an objective marker of sleepiness. What can be measured can be prevented.