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This is a guest post by Griffin Colaizzi, Williams College class of 2018.
I “woke up” the other morning and tried not to panic. I could not move. At all. I attempted to move any part of my body but to no avail. All I could do is glance around frantically. I lay there, breathing out of my nose because my mouth was closed and I couldn’t open it. I kept on looking at my ceiling, hoping I would eventually flinch and snap out of this state. When I finally did, I immediately sprang out of bed to avoid slipping into this “sleep paralysis” again.
Why does this happen? Think about it as gating. When you want to raise your left hand, you activate the “arm and hand” area of your motor cortex on the right side of your brain. This causes the muscles in your arm to move and you to raise your hand. However, your motor cortex does the same thing when you think about raising your hand! Of course, when you visualize moving your hand, your hand doesn’t actually move. Gating is the mechanism that prevents this movement. Because your motor cortex is active, this “blockage” of movement must happen downstream of your motor cortex.
What does any of this have to do with sleep paralysis? It all has to do with dreaming. In dreams we are often walking around or at least engaging in some movement. In order to prevent our bodies from moving while we sleep, we experience gating. When I experience sleep paralysis, I am awake (in a sense), but my body is still gating. This is preventing me from moving anything other than my eyes. (I can still move my eyes because we dream in Rapid Eye Movement (REM) sleep so clearly eye movements are not gated.) Sleep-paralysis is a case of the gate being closed when it should be open, but the reverse also happens. Under-gating is called sleep walking! When sleepwalking, we fail to experience gaiting while sleeping, and end up acting out our dreams.
Is gating only beneficial for preventing sleepwalking? No! Gating is also critical for visualization practices. As mentioned above, when you visualize yourself performing an action, your motor cortex still performs this action. Are there actually benefits to doing this? In a study done by Wohldmann, Healy, and Bourne (2008), participants practiced motor movements on a keyboard by either physically typing or mentally typing 4 digit numbers. Participants in both groups then proceeded to a test where they had to physically type 4 digit numbers. The study found that there was equal or better performance following the mental practice.
This means that simply visualizing yourself perform a physical task can make you better at this task. Imagine the possibilities: you can visualize yourself taking penalty kicks on your bus ride home, you can visualize yourself throwing a baseball while you walk to class, you can improve in almost anything physical just by imagining yourself doing that thing! All of this, of course, is thanks to the process of gating.
This is a guest post by Griffin Colaizzi, Williams College class of 2018.
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Sources:
Wohldmann, E. L.; Healy, A. F.; Bourne, L. E. (2008). Journal of Experimental Psychology: Learning, Memory, and Cognition, Vol 34, 823-833.
