Sleep and Stress: Understanding the Nervous System

Consider this: Imagine you are camping on safari in Africa.  If you thought there was a real possibility that a tiger was circling your camp, would you have difficulty falling asleep? If you did get to sleep, would a sudden movement in the tent wake you up?

Of course.

What would wake you up in this circumstance is your sympathetic nervous system, aka “fight or flight” mode, which is designed to keep you safe.  Its the mode your body goes into when there is a threat (or perception of a threat), and it prepares your body to either fight the threat, or run from the threat.  When the threat (or perception of the threat) has dissipated, your body is meant to shift back to your normal resting mode, your parasympathetic nervous system, aka “rest and digest.”

When in “fight or flight,” our body conserves energy by only activating responses that are critical to survival.  So our heart rate and blood-pressure increase, to help pump oxygen to our muscles, so we are as strong as possible to fight or flee.  Our digestion and sex-organs are inhibited, as we don’t want to be digesting lunch or distracted by procreation desires while we are running from a tiger.

Our “rest and digest” mode is a return to a state of equilibrium, where the body can relax and repair its self, and access a deep, restorative sleep.

Ideally, “fight or flight” is a short-term state, that is activated in the presence of a real threat, and then we shift back to “rest and digest,” which is where we want to spend most of our time.  However, often this short-term state, becomes a chronic state for people, as “fight or flight” is not only activated in the presence of real threats, but also in the presence of perceived threats.  Our body does not know the difference between a real tiger, and the thought of a tiger, responding to both with “fight or flight” activation.

So if people are in a chronic state of stress, they are in a chronic state of “fight or flight.”  Or if someone is worried about an upcoming event, or ruminating on a stressful event that has already happened, the body (not knowing there is no direct threat to physical safety), will activate “fight or flight” mode.

In addition to stressful thoughts, there is another common way the “fight or flight” mode is activated: caffeine consumption.  It is a vicious cycle, as people who don’t sleep well are often tired and groggy in the morning, and as a way of helping them get through the day, people often turn to caffeine.  Unfortunately, this can further activate “fight or flight,” and make it even harder to fall asleep at night, and contributing to that “tired but wired” feeling.

So if the “fight or flight” mode is activated, we won’t get deep, restorative sleep since the body is prepared to keep us safe.

The good news is you can learn to shift your body from “fight or flight” back to “rest and digest.”  Firstly, limiting caffeine consumption (ideally eliminating caffeine all together eventually) to small amounts, first thing in the morning will help the body shift into a “rest and digest” state at night.  Secondly, you can learn to use meditation and the breath, to activate the “rest and digest” state.

Taking slow, smooth diaphragmatic breaths (where you allow your stomach to expand on the inhale, and release on the exhale), can help shift into a relaxed state.   A guided meditation that focuses on the body and breath sensing can help send the signal to your body that its safe to sleep and shift from “fight or flight” to “rest and digest.”  Meditation can also help people deal with stressful thoughts, by learning to redirect attention back to the breath.

Remember, if you’re stressed, its because your body thinks there is a real threat to your safety. Use one of the tips above to help calm your nervous system down, or remind yourself that you’re in a safe place, that there is no tiger outside, and its safe to drift into a deep sleep.

Today there are many wonderful ways of learning meditation online, and below are a few helpful links.

Apps: Aura and Insight Timer and YouTube.