I suffer from brain-fog related to chronic fatigue. Getting about 20 mins sleep in the day is a fantastic recharge. Any more I find I don't sleep at night. I set a 30 min timer, 10 mins to drop off.

I’ve been devoting at least 20 minutes later in the morning to rest for months now. It really makes me incredibly sharper through the rest of the day.

Another thing I’m learning: blocking my eyes so I can focus on something I’m hearing to better absorb its content. Thinking of really good interviews with heady scientists or programmers.

Sleep apnea perhaps?

A nap of under 30 minutes never fails to reinvigorate. For that matter, a nap of even just one or two minutes brings a wave of refreshment. Nap evangelism!