Sleep Science
Your body clock is a physical structure, not a metaphor
It sits above the optic chiasm, it contains about 20,000 neurons, it keeps near-24-hour time in a dish with no external input, and the genes that run it won a Nobel Prize.
Sleep Science
Circadian rhythm, sleep stages and what the lab actually measures.
Sleep Science
What actually happens across a night of sleep
Sleep is not a single state you fall into and climb out of. It is four distinct conditions the brain cycles through, and the order they arrive in explains almost everything about how a night feels.
Sleep Science
Are you really a night owl? What chronotype is and how much of it is fixed
A substantial part of your preferred sleep timing is genetic and cannot be trained away. The rest is light exposure, which can — and the difference matters for anyone fighting their alarm clock.
Sleep Science
Insomnia: the treatment that works is not a tablet
Cognitive behavioural therapy for insomnia outperforms sedatives in the medium and long term, and its most effective component is the one that sounds like the worst possible advice.
Sleep Science
How much sleep do you actually need, and who decided on eight hours?
The recommendation is a population range, not a personal prescription. Individual requirement varies substantially, a rare genetic variant permits four hours without penalty, and both ends of the curve carry risk.
Sleep Science
The glymphatic system: what the brain does with its waste while you sleep
A drainage network described only in 2012 appears to run far more actively during sleep than wakefulness. It is one of the most exciting findings in the field and one of the most over-claimed.
Sleep Science
Caffeine, adenosine and the reason coffee stops working
Caffeine does not supply energy. It blocks the signal that tells you how tired you are, and the debt it conceals is still accruing underneath.
Sleep Science
Can you learn while you sleep? Almost none of what you have been told
The idea was tested seriously in the 1950s, discredited, revived by commercial products, and then partially rehabilitated by findings that are real, narrow, and much less useful than the advertising.
Sleep Science
Shift work and the clock that will not adapt
Around one in five workers in industrialised economies works outside standard hours. Full circadian adaptation is rare, and the reason is that everyone goes home to daylight on their days off.
Sleep Science
Naps: how long, when, and what the different lengths do
A twenty-minute nap and a ninety-minute nap are different interventions with different mechanisms. Getting the length wrong is what produces the grogginess that makes people conclude naps do not suit them.
Sleep Science
Blue light, screens and the evidence that is thinner than the marketing
Light does suppress melatonin and shift the body clock. Whether your phone at bedtime does enough of it to matter is a more interesting question than the blue-light-filter industry suggests.
Sleep Science
Sleep and the immune system: why you get ill after a bad week
Volunteers deliberately exposed to a cold virus are several times more likely to become infected if they have been sleeping badly. The mechanism runs through cytokines, T-cells and antibody response.
Sleep Science
Sleep, temperature and why the room should be cooler than you think
Core body temperature has to fall for sleep to begin, and the mechanism runs through the hands and feet. Which is why warm socks and a cool room are not contradictory advice.