Reading time
1 min read
Cat sleeping

Dear friends,

I received a copy of Why We Sleep: Unlocking the Power of Sleep and Dreams as a Christmas gift — back in the pre-Covid era — and finished it last weekend. This book by Matthew Walker, director of UC Berkeley’s sleep and neuroimaging lab, is a useful reminder of the importance of sleep for learning and also for physical and mental health.

Say you spend a few hours learning something new on Wednesday. Getting a solid night of sleep the same day will help consolidate the new memories and strengthen your long-term retention. If your sleep on Wednesday night is disrupted, your long-term retention will be affected even if you catch up on sleep later in the week.

But the story doesn’t end there. Over the next few days, your brain may still be busy consolidating the new learnings. A surprising study showed that even if your sleep is disrupted on Friday — two days later — long-term retention can still be significantly affected.

Bottom line: After you spend time studying during the day, I encourage you to get a good night’s sleep. Even better, try to get a good night’s sleep every night.

The world is going through turbulent times. With society buffeted by biological, social, and political forces, who has time for sleep?! I try to sleep from midnight to 8 a.m. every day, including weekends. With an 18-month-old daughter who wakes up whenever she wants, and occasional meetings with business partners in Asia or in Europe at odd hours, my sleep schedule is far from perfect.

You’re probably incredibly busy as well. Despite everything going on, I make sleep a priority, and I hope you will, too.

Keep learning,



Subscribe to The Batch

Stay updated with weekly AI News and Insights delivered to your inbox