Sleep

Are you a lark or an owl?

Larks are most alert around noon, and feel most productive at work a few hours before they eat lunch. They don't need an alarm clock because they invariably get up before the alarm rings - usually before 6 AM. Larks get drowsy in the early afternoon, and go to bed around 9 PM. About 10% of the population are larks.

Owls are most alert around 6 PM, experiencing their most productive work times in the late evening. They rarely go to bed before 3 AM, and most definitely need an alarm clock (with multiple alarms) to wake up. About 20% of the population are owls.

The rest of us, about 70% are hummingbirds, flitting back and forth on a continuum between more owlish behavior, or more larkish behavior, or somewhere in between. Our sleep patterns shift back and forth as our circumstances dictate.

Who's right? How much, and what kind, of sleep does a person need. The short answer: science doesn't know. However, studies have shown that whatever amount of sleep is right for you, when robbed of that (in either direction), bad things really do happen to your brain.

John Medina's "Brain Rules" gives 12 principles for surviving and thriving at work, home, and school. I've been looking at a few of the these this week, and the "sleep" brain rule has been an interesting one!

Sleep well, think well.

• The brain is in a constant state of tension between cells and chemicals that try to put you to sleep and cells and chemicals that try to keep you awake.


• The neurons of your brain show vigorous rhythmical activity when you're asleep - perhaps replaying what you learned that day.


• People vary in how much sleep they need and when they prefer to get it, but the biological drive for an afternoon nap is universal.


• Loss of sleep hurts attention, executive function, working memory, mood, quantitative skills, logical reasoning, and even motor dexterity.


• We still don’t know how much we need! It changes with age, gender, pregnancy, puberty, and so much more.


• Napping is normal. Ever feel tired in the afternoon? That’s because your brain really wants to take a nap. There's a battle raging in your head between two armies. Each army is made of legions of brain cells and biochemicals –- one desperately trying to keep you awake, the other desperately trying to force you to sleep. Around 3 p.m., 12 hours after the midpoint of your sleep, all your brain wants to do is nap.


• Taking a nap might make you more productive. In one study, a 26-minute nap improved NASA pilots’ performance by 34 percent.


• Don’t schedule important meetings at 3 p.m. It just doesn’t make sense.

Just be careful where you nap!