He (Prather, 2022, p. 5) focuses first on the process of homeostasis:
“Your homeostatic sleep drive is essentially “pressure” for sleep that builds up the longer you’re awake. Picture a balloon. It’s flat and empty the moment you open your eyes in the morning. As you go through your day, it gradually begins to inflate, filling up with sleepiness. When it’s at this optimal amount—picture a perfectly inflated balloon—you feel the need for sleep. Your eyes get heavy, you climb into bed, and drift off. When you take a nap, you’re basically “letting some of the air” out of the balloon, or relieving some of that sleep pressure.”
Prather’s analysis is certainly useful as a way to describe our growing desire for sleep as the day wears on. However, what if we operate not on the basis homeostasis, but rather on the basis of Peter Sterling’s Allostasis? This could mean that the balloon varies a bit in size, depending on what is happening in our body at any one point in time during the day. This being the case, then our desire to fall asleep will change from day-to-day (and even from hour-to-hour) depending on not just the level of the balloon’s deflation, but also the size of the balloon.
Alternatively, Allostasis suggests that it is not just the status of the balloon that determines our level of sleepiness; it is also a matter of how our body interprets the status of the balloon. We might anticipate that the balloon has a major impact on our waking state, or that it has a minimal impact. If we are taking a drink with caffeine, then our body is likely to discount or over-ride the balloon. Conversely, after drinking a warm cup of cocoa, and having just sat down by the fire after several hours of snow skiing, then our body might anticipate the balloon having a big impact and complementing the fatigue and drowsiness that our immediately past activities and our present consumption of a sleep-inducing beverage, warm fire, and comfortable chair provide.
Perhaps we should be referring to Allostatic sleep . . .
Polystasis and Circadian Cycles
We can push further. Aric Prather (2022, pp. 6-7) takes us to the second “driver” of sleep. This is our circadian cycle (or rhythm):
“Your circadian rhythm is, most basically, your “master clock” that governs the rhythm of all your body’s processes-including sleep and wakefulness. All of the cells in your body, all of your organs, including your brain, have rhythms. There’s an ebb and flow of processes and activity throughout the course of a twenty-four-hour day. That master clock that controls all of this lives deep in an area of the brain called the suprachiasmatic nucleus, or SCN, which is found in the hypothalamus, a small but influential area of the brain that controls everything from the release of hormones, to thirst, to body temperature, and more. It also determines your “alertness rhythm” throughout the day. In general, our alertness tends to spike higher in the morning, dip in the afternoon, rebound slightly, and then wane slowly through the evening until we need to go to sleep.”
Once again, we can expand on (and slightly alter) Prather’s description of the circadian rhythm by reintroducing the psychology of anticipation and the Polystatic process. As we consider the many things we anticipate during the day, some will inevitably have to do with how we “feel.” Some of how we “feel” (our somatic template) will be influenced by where we are on our circadian clock. We are at a high point when we have an abundance of energy (usually in the morning). Or are we finding it hard to keep our eyes open (usually in the afternoon).
