Everyone likes to think they’re in control of their own lives and, at the very least, their own bodies. Bodily autonomy is a thing that people talk about. Most people agree that you have the right to decide what you’re going to do for yourself. You can refuse medical treatment, if you want, for instance. You can get tattoos and piercings if you want. You can dress the way you want, you can do your hair the way you want. You have control. Except for when you don’t.
There are facets of your body over which you do not have control. This isn’t in terms of choices you make, but functions. Like the beating of your heart, for instance. While there are some exercises you can do to calm yourself down if your heart is racing, you typically can’t start your heart beating or stop it from beating at will. Which is a good thing, of course.
You can hold your breath, but most of us couldn’t do it to the point of actually passing out or dying. And if you did pass out, you would automatically start breathing again, provided there was nothing else preventing you from doing so.
Digestion, the flow of blood, and things like hormones throughout your body are all done without any input from your conscious mind. So, how does your body decide what you can control and what you can’t? And what about the things over which we have some limited control, like breathing, or when you go to the bathroom? Let’s take a look at the remarkably complex machine that is you and, in particular, your nervous system.
Nervous Systems in General
You have two nervous systems in your body, at least technically. One is the central nervous system and one is the peripheral nervous system. However, the peripheral can be broken down even more. The peripheral includes your autonomic nervous system and your somatic nervous system.
Your peripheral can also be broken down further to include the sympathetic, the parasympathetic, and the enteric nervous systems. We’re not going to cover all of that, but we’ll start with the sympathetic nervous system, and then look a bit at the autonomic and somatic and see how they relate to what it is you can control in your body.
The central nervous system is your brain and your spinal cord, which receives and responds to all sensory data. Your enteric nervous system controls your digestive system and does fall in line with things you don’t control, but is also not super relevant to the rest of the point, so we’ll ignore that, too. Let’s just focus on the peripheral and branch out from there.
Peripheral Nervous System
If your central nervous system is like the hard drive of a computer processing and responding to information, the peripheral nervous system is all the plug-and-play devices that are attached to it. All the cables, the cameras, the keyboard, and whatever else you have. This is what transmits information to and from the central nervous system.
The information communicated through your peripheral nervous system to your central nervous system is what controls all the functions in your body that you have no conscious control over. Basically, whatever nervous system isn’t your brain or your spinal cord is the peripheral nervous system. So these are the actual nerves that run through your body, and any other sensory receptors that you have.
The peripheral nervous system can be broken down into the autonomic nervous system and the somatic nervous system. Everything it does is controlled by those two systems. That covers all of your senses, like touch, smell, sight, as well as all the movement your body does, and all the unconscious processes that are happening inside your body all the time. That’s what we want to take a look at.
Autonomic Nervous System
Your autonomic nervous system connects your brain to most of the organs in your body. So everything that your liver, your heart, your lungs, and so on do is governed by the autonomic nervous system. Much of this is obviously unconscious. Things like your eyes are covered by the somatic nervous system because you have conscious control over those, although the function of seeing once your eyes are open, in terms of pupil dilation and such, would be part of the autonomic nervous system.
As mentioned earlier, your autonomic nervous system can be broken down into the sympathetic, parasympathetic, and enteric nervous systems.
The sympathetic nervous system is sometimes called the fight-or-flight response. This essentially governs everything that has to do with stress in your body. This can include your heart rate, blood pressure, and sweating, but also digestion and urination.
Conversely, your parasympathetic nervous system is sort of the opposite. In fact, one of the nicknames for this one is the rest and digest system. While sympathetic can help you during stressful times, parasympathetic is for non-stressful times. What it controls is essentially the same, just not when you need a stress response. So it can tighten airways to make your lungs relax, or lower your heart rate, or anything needed to help you stay calm and cool.
Although it sounds simple on paper, there is a lot of complicated coordination that goes on throughout the autonomic nervous system to maintain the delicate balance that is your day-to-day functionality as a living, healthy being.
Consider the enteric nervous system that we touched on before. This controls your digestion, but it begins with the salivary process in your mouth. When you are about to eat food or you first taste that food, your mouth produces saliva, which begins the digestion process. That function is controlled by your nervous system. The passage of food down into your stomach, the muscle contractions that force the food bolus along, the whole process of digestion and food being moved through your stomach into your intestines is all controlled by the same system, like a factory that has a beginning, middle, and end to the line of production. And that’s just one process.
The vagus nerve network is responsible for much of the information sent from organs to the brain stem and ultimately the brain, and it is vastly complex. So much so that we have only just begun to understand how these nerves interact with our brain in organs and how data is transmitted between them and processed.
It is the vagus nerve that is ultimately responsible for things like digestion, heart rate, breathing, blood pressure, sensations you feel through skin and muscle, urination, speech, immune response, and even your sense of taste.
With 100,000 fibers traveling to the base of the brain and back, the vagus nerve network covers as many as 37 types of sensory neurons that can react to all kinds of stimuli, including pressure, toxins, nutrients, and even stretching. And they transmit not just to the brain stem but to much more complex sections of the brain which deal with memory, emotion, and our overall sense of self. Meaning these automatic processes are far more in-depth than any of us know.
Somatic Nervous System
Your somatic nervous system is a little easier to understand. That’s thanks to the fact that we actively engage with it all the time. While your autonomic nervous system controls everything unconsciously, your somatic nervous system is what you have conscious control over.
When you decide to put one foot in front of the other and go for a walk, that’s your somatic nervous system at work. When you pick up your phone and start scrolling through social media, your somatic nervous system is controlling the muscles in your hands, your arms, and even the movement of your eyes as you read the screen. Anything that you choose to do with your body is controlled by your somatic nervous system.
A series of nerves control most of our conscious body functions. Ten cranial nerves that come from the brain stem control most of the movements of the head, for instance. Most of the peripheral nervous system is made up of 43 nerves, including the vagus nerve we mentioned earlier. Thirty-one pairs of these nerves come from the spine, while 12 pairs are cranial. All the movements of your body, including reflex actions, are governed by these nerves and the data they receive and transmit.
Can You Consciously Control Autonomic Functions?
So why is it you have control over your somatic system but not your autonomic system? What is the function by which one is conscious and one is not? And how is it that you can’t exert any control over those autonomic functions? Or at least, not any great degree of control.
After all, it is possible to hold your breath. And, as we mentioned earlier, it’s possible to do exercises that can slow your heart right down. People who have mastered meditation can slow their heart rate down incredibly. There is also evidence that conscious control of breathing methods and contractions of abdominal muscles can change the heart rhythm and even bring on cardiac arrest.
Certain monks have been shown to exert control over their own body temperature during meditation. They managed to increase the temperature of their fingers and toes by over 8 degrees C. That’s over 46°F. They can also significantly raise and lower their metabolism.
Wim Hof, sometimes called the Iceman, has been studied for his ability to endure incredibly cold temperatures for extended periods of time. It has been shown that Hof has the ability to consciously activate his sympathetic nervous system. He is able to release epinephrine and suppress immune responses to the cold and it’s not a result of weird genetics. He has taught the technique to others.
The use of biofeedback has proven valuable in giving people some minor control over their autonomic nervous system functions. Through sensors that measure these unconscious actions, such as breathing, heart rate, and muscle response, a participant can see the data presented on a computer as it happens. If there is a pain response, for instance, you can watch your breathing and heart rate increase, and your muscles tense. This allows you to focus on those things and consciously put effort into changing them. You can focus and slow your heart rate, slow your breathing, and relax your muscles.
Controlling autonomic functions with the aid of biofeedback has been shown to aid people dealing with various medical conditions, including diabetes, where it, along with relaxation techniques, has been shown to lower blood glucose levels, and ADHD.
Other people have demonstrated an ability to voluntarily give themselves goosebumps, something traditionally governed through unconscious nerve response.
While much of this requires some extensive practice and meditation, there are simpler ways to get some mild control over your autonomic functions. The simplest way to do this is through deep breathing exercises, muscle control, and even your imagination. Since the sympathetic nervous system is your fight-or-flight response, and your parasympathetic is the rest and relax, you can switch from the sympathetic to the parasympathetic by forcing yourself to relax.
Obviously, it’s not as complex as being able to raise the temperature of your fingertips or withstand freezing cold temperatures, but you can lower your heart rate and your pulse as a result.
In simple terms, you want to start by slowly breathing in through your nose and holding it for five seconds, then breathing out through your mouth. Pause for ten seconds, then start again.
Muscle relaxation techniques involve tightening or flexing all the muscles you can from one group, like your face or arms, back and shoulders, legs, or abdomen, holding for five seconds, then releasing for 10 seconds. You only need to do this a couple of times, but cycle through all your muscle groups.
In terms of imagination, this is very Fight Club. You can find a happy place for yourself, just an image you hold in your mind that is relaxing and peaceful to you. That’s about as complicated as it needs to be.
By and large, you will never gain full control of your autonomic functions and, honestly, you probably don’t want to. Who wants to forget to salivate or excrete urine? But with practice, you can get some control if you’re very committed to it.