Autonomic Nervous System
Think of the Autonomic Nervous System (ANS) as your “automatic” nervous system. It controls involuntary functions, like heart rate, breathing, digestion, and your body’s response to stress. Working constantly behind-the-scenes—even while you’re asleep—the ANS keeps you balanced and ensures your survival.
WHERE IS THE AUTONOMIC NERVOUS SYSTEM?
The ANS isn’t confined to a single place in the body. It’s a network that connects the brain and spinal cord with various organs and tissues throughout the body, from your eyes to your gut. The ANS sends signals to organs like your heart, lungs, digestive organs, blood vessels, skin, and glands—allowing it to coordinate responses in multiple areas at once.
Central Nerves (Brain and Spinal Cord): The ANS control center, located in the brainstem and hypothalamus, sends signals down the spinal cord to reach organs and tissues throughout the body.
Peripheral Nerves: Branches from the spinal cord extend to various organs, where the ANS influences muscle contractions, hormone release, and gland activity. For instance, ANS signals can increase or decrease heart rate, dilate pupils, and adjust blood flow as needed.
THE THREE MAIN BRANCHES OF THE ANS
Each branch of the ANS has specialized roles, and they often work in balance to help you respond, recover, and adapt to changes in your environment:
Sympathetic Nervous System (SNS) – “Fight or Flight”
This system prepares your body to respond to stress or danger, increasing alertness and energy. Known as the “fight or flight” response, the SNS directs energy to muscles, dilates your pupils to improve vision, increases heart rate, and even slows digestion temporarily to conserve energy for immediate action.
Parasympathetic Nervous System (PNS) – “Rest and Digest”
The PNS works in opposition to the SNS, calming the body after a stress response and promoting relaxation. Often called the “rest and digest” system, it slows the heart rate, stimulates digestion, and supports recovery processes. Its signals focus on restoration, helping you to relax and regenerate energy.
Enteric Nervous System (ENS) – The “Second Brain” in the Gut
The ENS, also called the “second brain,” operates independently within the gut but stays in close communication with the brain. It manages digestive functions like the movement of food through the intestines and the release of digestive enzymes. The ENS is part of the gut-brain axis, a connection that links digestion with mood and even cognition.
WHY UNDERSTANDING THE ANS MATTERS
No one system is more important than the other—just like no part of a car (brakes, gas pedal, or steering wheel) is more essential than another. We need them all in harmony because they affect our body, mind, and spirit.
These systems shape our daily experiences of stress, relaxation, digestion, and even immune and hormonal health. When they’re out of balance, we feel it. If our SNS is chronically active, keeping us in “fight or flight,” we might feel tired and wired, experience persistent feelings of anxiety or irritability, digestive issues, or have increased sensitivity to stimuli. On the other hand, if we’re too parasympathetic-dominant, with low SNS activation, we might experience symptoms like lethargy, low energy, difficulty getting motivated, slower reaction times, or poor stress tolerance.
And all of this affects our enteric nervous system, which is also influenced by our diet. What we eat impacts our microflora (healthy gut bacteria), which communicates with us through our nervous and immune systems.
IN THE MEANTIME
Over the next few posts, we’ll break down each of these systems to understand how they work and how we can support them to create harmony for optimal health.
In the meantime, a great way to start supporting your nervous system is to simply observe your experience. Notice your breath throughout the day—is it shallow? Are you sighing a lot? Are you breathing from your chest and shoulders, or from your belly? How do you feel before and after you eat? What’s your sleep like?
Don’t worry about what any of this means for now—just notice, and keep these observations in mind as we dive deeper in the coming posts. I look forward to guiding you through ways to support your nervous system over the next few weeks!
What's coming:
The Autonomic Nervous System - The Intro
The Sympathetic Nervous System - "Fight or Flight"
The Parasympathetic System and the Vagus Nerve - "Rest & Digest"
The Enteric Nervous System - The Gut-Brain Connection
The Somatic Nervous System - Move & Sense
The Cranial Nerves - Pathways of Sensory and Motor Control
Brain Regions and Their Roles in Thought, Mood, and Movement
How the Nervous System Impacts Mental Health & Trauma Recovery
Craniosacral Therapy - Enhancing Nervous System Balance
Are there specific areas of the nervous system you're curious about? Drop a comment below, and I'll be sure to cover them as we journey through this incredible body-wide network!
