Part II: The Shared Nervous Symphony; Scent and the Olfactory Bridge Between Dogs and Humans

By Erin Alefounder, Soul Paws Massage & Wellness

Introduction: Smell as Soul Communication

When I utilize holistic aromatherapy blends into a bodywork session — whether it’s for a senior golden retriever with stiff hips, a dog with an autoimmune disorder, or an anxious dog whose in a chronic state of "fight or flight" — I know I’m doing more than offering a “nice smell.” I’m opening a two-way emotional conversation, one that travels through the nervous system, bypasses logic, and goes straight to the heart (and gut).

Scent doesn’t just float through the air; it moves through our biology. It binds to memory, emotion, and safety. In both humans and dogs, the sense of smell is a direct line to the nervous system’s emotional control centres — the amygdala, hypothalamus, and the vagus nerves.

It’s this olfactory–limbic–vagal connection that allows us to influence deep healing, calm, and even intuitive alignment — one inhale at a time.

Dog's Vs Human's Olfactory Bulbs & Receptors

Dogs Smell in Stereo — And Emotionally

We often say dogs have “better noses,” but that’s an understatement. A dog’s olfactory bulb is about 40 times larger proportionally than a human’s (Furness, 2023). With over 220 million olfactory receptors (compared to our ~6 million), they process scent at a nearly 100,000-fold sensitivity advantage.

But it’s not just about detection — it’s about interpretation. Dogs don’t simply identify a scent; they feel it. Emotional memory, body state, and environmental signals are all rolled into their olfactory experience.

Their nasal architecture supports this in a fascinating way:

• Humans have ONE olfactory pathway for both breathing and smelling.

• Dogs have TWO: one for respiration and temperature regulation, the other specifically for scent analysis (Lepri & Wysocki, 2020).

• Dogs' scent-only pathway travels directly to their huge olfactory bulb, which lives next to their limbic system and vagus nerve.

The Olfactory–Limbic–Vagal Axis: How Smell Changes the Body

Unlike sight or touch, smell bypasses the brain’s relay centre (the thalamus) and goes straight to the limbic system — the brain’s emotional hub. This includes:

• Amygdala: emotion processing (fear, pleasure, safety)

• Hippocampus: memory storage

• Hypothalamus: autonomic and hormonal regulation

This is also where the vagus nerve receives regulatory input — smell directly alters heart rate, breath, and digestion as well as the immune system.

How Your Dog Feels Your Emotions and Hormones in Seconds

You walk in the door after a long, stressful day at work, and although you look forward to seeing your dog, you cannot help but still feel stressed, either from the traffic en route home or the work issue or both! Your dog sees you, wags his tail with joy to know you're back home. You then call your friend and tell them the crazy day you had. Then while petting your dog on the sofa, you notice his ears smell moist with excess yeast and his nose and paws have a little redness showing. Your dog has not only smelled the cortisol (stress hormone) you accidentally carried inside the home, but has co-regulated and his immune system has reacted and in overdrive (redness, overactive yeast).

Co-Regulation Through Scent

When you and your dog inhale a calming blend together:

1. You relax, your heart rate slows.

2. Your pheromones and skin VOCs shift.

3. Your dog detects this change and responds biologically.

4. Their vagus nerve activates — digestion improves, muscles soften, breath deepens.

This is co-regulation — the mutual calming of two nervous systems. And it’s measurable: heart rate variability (HRV) studies show increased vagal tone when humans and dogs share calm, aromatic environments (Di Natale et al., 2023).

How Specific Scents Act As Neurochemical Messengers to Your Body (And Your Dog's)

Every time I mention "aromatherapy" to a friend, they immediately say something to the effect that many of the scents smell nice, and that they want to buy their mom a scented candle...but that's about it. I know, I used to say the same...until I learned how different scents bind to different neurochemicals in your brain (which includes your limbic system and vagus nerves that link to all major organs) and which have major effects on the body. Seriously...why is this not more a thing? Here are just a few of my favourite scents that help reduce stress and put the body's parasympathetic system into rest, digest and heal mode:

• Apomorphine and nuciferine (Blue Lotus) modulates dopamine, calms the amygdala and reduces sympathetic (fight/flight) arousal.

• Linalool (Lavender, Neroli, & Blue Lotus): binds to GABA-A receptors to lower cortisol and heart rate variability (HRV) and stimulates the vagus nerve for relaxation (Linck et al., 2010)

• β-Caryophyllene (Copaiba): activates and binds to CB2 cannabinoid receptors for inflammation reduction and immune modulation (Gertsch et al., 2008)

• alpha-pinene and incensole acetate (Frankincense/Boswellia) modifies the hypothalamic-pituitary-adrenal (HPA) axis promoting calm, and reducing inflammation.

• Citral/Neral (melissa): balances parasympathetic tone and sleep–wake rhythm (Soares et al., 2021)

• Jatamansone (Spikenard) is a natural sedative and GABA modulator that slows brain waves, enhances parasympathetic states and regulates the emotional centres linked to the vagus nerves.

These compounds entrain the nervous system — reducing sympathetic overdrive and activating parasympathetic healing. This is true for humans and for dogs! However if you can first ensure you are calm, your dog will be calm too. From there, magic can happen through scent, intentional bodywork and relaxation.

Heart Rate Variability alignment through co-regulation between guardian/practitioner and dog.

This is the subtle magic behind massage sessions. Often, a dog won’t relax until their human does. And when I am working on a dog with a stressed out guardian in the room, I may give them something important to read or show them a technique or two so that they lower their shoulders, relax and focus on something beneficial for their beloved. It is important for not only the guardian but also the practitioner, vet or other guardian involved with the dog that they know how to regulate their emotional state to be calm and relaxed. Remember, dogs feel in 3D through smelling, and they co-regulate with their people.

When the day is too stressful, there are special aromatic blends that can help bridge the divide and allow safety to be felt — simultaneously, and silently. And if you cannot unwind your stressful day, try to have the massage practitioner in another room so they can calm your dog and induce parasympathetic co-regulation where healing thrives. There’s no judgement or pressure as we live in the world where jobs are often brought home if not directly, sometimes through our stress and hormonal imbalances.

Intuition, Interoception, and Scent

The vagus nerve doesn’t just calm us — it gives us access to our internal signals (interoception), which is the biological basis for intuition. When your vagus nerve is overactive from stress, trauma, or noise, those internal whispers get lost.

Smell restores the signal.

Essential oils help balance the vagus and clear glial cell inflammation (Grubišić & Gulbransen, 2017), enhancing sensory clarity. This is why clients often describe feeling “clearer,” “lighter,” or “more themselves” after aromatic massage — their body’s radio signal was retuned.

Dogs, with their enhanced olfactory–vagal link, remain deeply intuitive. They feel truth through scent. They co-regulate with our chemistry — not our words.

Practical Application at Soul Paws

All my blends are crafted with globally sourced holistic oils to stimulate specific nervous system pathways. The Soul Hands blends are solely for human use while the Soul Paws blends are specifically blended for dogs.

Some blends are geared for:

• Anxiety reduction & vagus nerve activation (Vagus Nerve Reset)

• Inflammation & pain reduction (Inflammasoothe)

• Immune Boosting (Shinrin Calm)

• Vestibular & Balance support (Equilibria)

 (Available January 9th, 2026 - pre-order now via email: erin@soulpawsmassage.com

Final Thoughts: Scent as a Bridge

Aromatherapy is more than scent — it’s biochemical-communication.

When used with intention, it becomes a healing bridge between you and your dog — one that reaches through time, memory, and emotion, right down to the gut and heart, courtesy of our vagus nerve.

The next time you take a breath with your dog beside you, remember:

you’re not just sharing air — you’re sharing biology, nervous rhythm, and emotion.

Take a few deep breaths (box breathing), lower your shoulders, visualize something that puts a genuine smile on your face, and watch your dog melt into co-regulation.

And that’s how healing begins and thrives – in the parasympathetic state.

Other modalities intensify parasympathetic stimulation including specific massage techniques, TTouches and calming supplements such as melatonin and L-Theanine. Just remember that healing thrives in the parasympathetic nervous state.

In Part III, we’ll bring it all home with a practical exploration of immune system regulation, chronic stress relief, and multimodal healing — from massage and infrared therapy to CBD, adaptogenic support, and vagus-stimulating touch techniques. You’ll learn how these tools create lasting change at the nervous system level — not just in theory, but in touch, smell, and experience. We’ll also look at a few powerful massage and breath-work techniques you can do on yourself while your cuddled up next to your furbaby and watch how they adapt to your internal state of mind.

References

·      Di Natale, C., et al. (2023). Heart rate variability and olfactory co-regulation in human–canine interactions. Journal of Animal–Human Bond, 45(2), 103–115.

• Furness, J. B. (2023). Comparative anatomy of the olfactory system. Comparative Physiology Reviews, 12(4), 210–224.

• Gertsch, J., Leonti, M., Raduner, S., et al. (2008). Beta-caryophyllene is a dietary cannabinoid. Proceedings of the National Academy of Sciences, 105(26), 9099–9104.

• Grubišić, V., & Gulbransen, B. D. (2017). Enteric glia: The most intuitive gut guardians. Nature Reviews Gastroenterology & Hepatology, 14(3), 157–167.

• Komiya, M., et al. (1995). Lavender aromatherapy and parasympathetic tone. International Journal of Aromatherapy, 7(1), 30–36.

• Lepri, J. J., & Wysocki, C. J. (2020). The vomeronasal organ and mammalian pheromone detection. Chemical Senses, 45(2), 189–203.

• Linck, V. M., et al. (2010). Inhaled linalool induces sedation via GABA-A modulation. Phytomedicine, 17(8–9), 679–683.

• Soares, M., et al. (2021). Melissa officinalis and parasympathetic activation via citral compounds. Journal of Ethnopharmacology, 264, 113251.