The Nervous System
By Liah Tsotros - Traditional Chinese Medicine
The nervous system is an intricate web that allows our brain to communicate with our body. It’s divided into two main parts:
The Central Nervous System (CNS) – the brain and spinal cord, responsible for processing and sending information.
The Peripheral Nervous System (PNS)– the network of nerves that connects the CNS to the rest of the body.
Within the PNS, we have the Autonomic Nervous System (ANS), which regulates unconscious bodily functions like heart rate, digestion, and breathing. The ANS has two branches:
The Sympathetic Nervous System – our “fight or flight” response. This system kicks in when we face stress or danger, increasing alertness, heart rate, and respiratory rate to help us react quickly.
The Parasympathetic Nervous System – our “rest and digest” response. Once the threat has passed, this system restores balance, slowing the heart rate and promoting a recovery state.
When functioning properly, these two systems work in harmony, keeping us adaptable to life’s demands. However, chronic stress, trauma, or illness can dysregulate the nervous system, leaving us stuck in a heightened state or unable to properly rest and recover.
The Vagus Nerve
The vagus nerve is the longest cranial nerve in the body, running from the brainstem down through the neck and into the chest and abdomen. It acts as a communication superhighway between the brain and vital organs, helping regulate heart rate, digestion, and emotional responses.
One of its key roles is in the parasympathetic nervous system, where it signals the body to shift from “fight or flight” into “rest and digest.” When the vagus nerve is functioning well, it helps:
Slow heart rate and lower blood pressure\
Support digestion and gut motility\
Reduce inflammation\
Regulate mood and emotional resilience
What is Vagal Tone?
Vagal tone refers to the strength and efficiency of the vagus nerve’s signaling. A high vagal tone is linked to better stress recovery, improved digestion, and a more balanced nervous system. A low vagal tone, on the other hand, can contribute to chronic stress, digestive issues, and difficulty shifting out of a heightened state.
Modern life tends to keep people stuck in a sympathetic state, meaning the vagus nerve isn’t always activated as it should be. This can contribute to issues like anxiety, poor digestion, and chronic inflammation.
Pain and the Nervous System
Pain isn’t just a sensation—it’s a complex process involving both the body and the brain. The nervous system plays a key role in how we perceive and process pain, with two main pathways involved:
The Peripheral Nervous System (PNS): Detects pain signals through specialised nerve endings called nociceptors and sends them to the spinal cord.
The Central Nervous System (CNS): Processes these signals in the brain, determining their intensity and emotional impact.
Chronic pain is often due to nervous system dysregulation rather than tissue damage alone.
The brain and spinal cord are adaptable, but sometimes, they learn pain patterns too well. This process, known as central sensitisation, makes the nervous system more sensitive over time, causing it to amplify pain signals (even in response to minor stimuli), continue sending pain signals even after an injury has healed and affect mood, sleep, and overall well-being
Conditions like fibromyalgia, migraines, and neuropathy are often linked to this maladaptive pain processing. When the nervous system is stuck in overdrive, breaking the cycle of pain requires more than just treating symptoms—it requires retraining the nervous system itself.
How Acupuncture Influences the Nervous System
Acupuncture is often thought of as a treatment for pain, but its effects go much deeper—it directly interacts with the nervous system, helping to regulate stress responses, modulate pain, and restore balance.
Regulating the Autonomic Nervous System (ANS)
One of acupuncture’s most well-documented effects is its ability to shift the body out of a sympathetic (fight-or-flight) state and into a parasympathetic (recovery) state. Studies suggest that acupuncture can:
Lower cortisol levels (the body’s primary stress hormone)
Slow heart rate and reduce blood pressure
Promote relaxation by activating parasympathetic pathways
This is why many people feel deeply relaxed or even sleepy after a treatment—it’s the nervous system downshifting into a state of recovery.
Stimulating the Vagus Nerve
Since the vagus nerve plays a key role in relaxation and overall nervous system health, stimulating it can improve digestion, mood, and resilience to stress. Acupuncture may support vagal tone by:
Encouraging the release of neurotransmitters like serotonin and acetylcholine
Enhancing heart rate variability (a marker of nervous system balance)
Modulating gut-brain communication, supporting digestion and inflammation control
Certain acupuncture points, particularly those on the ears and along the neck and abdomen, are known to influence the vagus nerve directly.
Modulating Pain Signals
Acupuncture doesn’t just block pain—it helps rewire how the nervous system processes it. Research shows that acupuncture:
Increases the release of endorphins, the body’s natural painkillers
Influences the brain’s pain-processing centers, reducing the intensity of pain signals
Decreases neuroinflammation, which is often linked to chronic pain conditions
By interrupting pain pathways and encouraging nervous system adaptability, acupuncture can be a powerful tool for breaking the cycle of chronic pain.
Ultimately, acupuncture acts as a regulator—bringing an overstimulated nervous system back into a state of equilibrium. Whether someone is stuck in a chronic stress response, experiencing nervous system fatigue, or dealing with persistent pain, acupuncture helps recalibrate these patterns so the body can function optimally.
The nervous system is the foundation of how we experience the world—regulating stress, pain, and recovery. When it becomes dysregulated, it can impact nearly every aspect of health. Regulating the nervous system is the number one priority to restore balance, enhance nervous system function, and support overall well-being.
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