I’m going to write about sleep deprivation because I am deprived (and depraved, but no amount of rest will fix that). Something I realised when I was doing the topic on sleep in a neuropsych unit, was that it is possible to sleep more efficiently.

To explain: Sleep involves a number of stages which can be distinguished by looking at brain activity. Stage I is very light and people woken from it may not even realise that they were asleep. The stages get progressively deeper with less and less activity until Stage IV, where people will usually be quite groggy if woken. But after that something strange happens: REM sleep. Named after the Rapid Eye Movements that occur, during this stage the brain activity suddenly jumps up to levels that look like Stage I or even consciousness. What’s even more interesting is that this appears to be when all the important bits of sleep happen. This is when you dream, and when you get, literally vital, rest (rats deprived of REM sleep die, rats deprived of the same amount of non-REM sleep do not). If you don’t get enough REM sleep you actually accrue a “REM-debt” where your body tries to make up the lost REM sleep next rest.

Sleep follows a roughly 90 minute repeating pattern of reducing brain activity through the stages, a sudden jump for REM sleep before dipping just as quickly down again and gradually rising back up to stage one. You only spend a small fraction of sleep in the REM stage. However, this cycle alters when sleep deprived. Your brain will progress more quickly into REM stage and will stay there longer. This means that a REM debt gets paid off quickly and even long periods of sleep deprivation can be recovered from within a relatively short time of healthy sleeps. (If only my financial debts worked this way!)

When I learned about this change it occurred to me that it might be possible to train yourself to get more REM sleep. People can train themselves to change many body rhythms when made aware of them (e.g. heartbeat rate, on a biofeedback machine anyone can quickly learn to alter their heart-rate at will). Unfortunately, since you are, by definition, asleep at the time it’s difficult to implement training. My thought was that if a machine was programmed to give a pleasant sensation (intracerebral drugs?) as long as you were in REM it might be possible to train the body to stay in REM stage longer. Effectively sleeping more efficiently. Of course there might be hitherto unknown necessities in non-REM sleep (sleep is not a well understood phenomena), but we can only know by trying, right? (-:

Unfortunately, lacking such a machine there is only one way to increase sleep efficiency and that is with deprivation. Although I only got 90 minutes sleep last night (deliberately timed it to give myself a full sleep cycle, which I’ve found is a great way to get the most out of a small amount of sleeping time) tonight I will have recovered most of my REM debt and therefore slept at nearly 200% of normal efficiency.

So last night I was not “burning the midnight oil” nor was I “pulling an all-nighter”. Instead I was “working on my sleep efficiency”.