What is a nap#
A question most people think is already settled
Where this starts#
There is no previous week. So: the nap is a biological need that modern work schedules erased.
Twelve weeks on its science, its history, and its return.
Today is the first of those.
The course’s claim#
- most adults feel a dip in alertness in the early afternoon
- most institutions are built as though they don’t
Both halves of that sentence are worth a semester.
Sleep is a sequence, not a state#
Light sleep, then slow-wave sleep, then REM. Then back around.
Roughly ninety minutes for a full lap.
Not one thing you are either doing or not doing.
Not a small night’s sleep#
An entry into that sequence, stopped partway
So what decides how you feel#
Which stage you were in when the alarm went.
- not how tired you were beforehand
- not whether you are “a nap person”
One variable, and it is the one nobody tracks.
Why this is not obvious#
The experience of napping is a poor guide to it.
People routinely cannot tell whether they slept — and are confident either way.
So we are not going to settle this by asking the room.
What we can measure, and how badly#
- self-reported sleepiness
- reaction time
- from week 10 — the devices that claim to do better than both
Every one of those is an approximation. Knowing which kind is the skill.
This week’s lab#
Locating your own dip.
- notice roughly when in the day your alertness drops
- change nothing while you do it
- do not look anything up first
Week 4 is about why it is where it is.
Who here is bad at napping?#
Nobody is bad at napping. People are bad at choosing a length, and the length is not a matter of temperament.