The Science Behind Alveos

Part 1: Acoustic Monitoring — From Breath Sound to Body State

For years, scientists and medical professionals have recognized that the sounds of breathing reveal critical information about our health. Alveos harnesses this powerful connection using advanced acoustic sensing technology.

From Sound to Nervous System State

It is a complex acoustic and mechano-acoustic signal that reflects your breathing rate, depth, regularity, and the mechanics of chest- versus diaphragm-driven breathing [1, 7, 8].

This pattern is directly controlled by your Autonomic Nervous System (ANS):

Sympathetic State (Fight-or-Flight): When you are stressed, your ANS triggers a rapid, shallow, and often erratic breathing pattern, primarily using the chest muscles. This produces a distinct acoustic signature.

Parasympathetic State (Rest-and-Digest): When you are calm, your ANS promotes a slow, deep, diaphragmatic breathing pattern. This produces a smoother, different acoustic fingerprint.

Our technology is trained to identify these subtle acoustic patterns, which are strongly coupled to how activated or relaxed your nervous system is. This provides an emerging biomarker of your autonomic state, all from a non-invasive wearable sensor.

The Evidence

Accuracy in Real-World Conditions

Acoustic respiratory monitoring delivers medical-grade accuracy in real-world conditions. Clinical validation studies demonstrate that acoustic devices achieve respiratory rate measurements within clinically relevant margins of error, typically under 3 breaths per minute deviation from gold-standard reference devices, even in the presence of physiological noise like coughing or movement [1, 2, 3].

Beyond the Lab

Wearable and contact acoustic respiratory sensors have proven effective in high-risk clinical environments, including continuous monitoring during procedural sedation and anesthesia [3, 6], as well as long-duration, noninvasive tracking of breathing patterns using tracheal and chest acoustic signals [4, 5]. Compared to traditional spot-check or tethered methods, acoustic monitoring enables continuous, unobtrusive measurement without bulky masks or invasive tubing [5]. These systems have been validated for detecting respiratory rate, irregular breathing, and early signs of respiratory compromise in real time [4, 5, 6].

Mechano-Acoustic Biomarkers

Advanced accelerometer contact microphones can detect pathological mechano-acoustic signals emanating from the lungs, enabling both episodic and longitudinal assessment of breathing patterns and respiratory health [7]. The technology leverages high-precision sensors to capture weak, high-frequency vibrations occurring on the skin surface due to underlying respiratory activity—providing unprecedented insight into your breathing in everyday life [7, 8].

Part 2: Breath Control — A Direct Handle on Your Nervous System

Scientific research supports what ancient practices have known for millennia: breathing is a uniquely accessible autonomic function you can consciously control, making it a powerful, bidirectional channel between your mind and your body [10–16, 23].

The Breathing-Brain Connection

HRV as a Window Into Wellbeing

Heart Rate Variability (HRV)—the variation in time between consecutive heartbeats—serves as a reliable biomarker of autonomic nervous system function and overall health [9]. Higher vagally-mediated HRV is a sign of a healthy, adaptable nervous system, indicating better cardiovascular health, stress resilience, and emotional regulation [9].

Slow Breathing Activates the Vagus Nerve

Multiple systematic reviews and meta-analyses confirm that voluntary slow breathing (typically 5-6 breaths per minute) significantly increases parasympathetic nervous system activity, as measured by increased vagal-driven HRV [10, 11, 12, 14, 23]. This is a direct biological mechanism, not a placebo effect:

Stimulating Receptors: Slow, deep breaths fully engage the diaphragm, which stimulates pulmonary stretch receptors in the lungs and modulates baroreceptors (pressure sensors in your arteries).

Signaling the Brain: These receptors send signals up the vagus nerve to your brainstem, effectively signaling "safety."

The "Vagal Brake": In response, the brain sends signals back down the vagus nerve to the heart, telling it to slow down. This "vagal brake" on the heart is what creates the healthy, high-amplitude rhythm known as Respiratory Sinus Arrhythmia (RSA)—the physiological source of high HRV [14, 23].

Measurable Brain Changes

This effect isn't limited to the heart. fMRI research reveals that controlled breathing activates brain regions critical for emotional regulation, interoception (awareness of internal states), and focus, including the prefrontal cortex, insula, and amygdala [14]. It strengthens "top-down" coupling, allowing your brain's executive centers to help regulate autonomic function.

EEG studies show that slow breathing reliably increases alpha wave activity (associated with relaxed alertness) [14]. The effect on theta waves is more nuanced: while sometimes decreasing (indicating less drowsiness), it can also increase in certain tasks, suggesting a state of focused, internal attention rather than just "zoning out" [14].

Psychological Benefits Backed by Data

Clinical trials demonstrate that regular slow breathing practice leads to:

• Reduced anxiety and depression scores [15, 16]

• Lower perceived stress levels [15, 16]

• Improved cognitive performance and decision-making [12, 13]

• Enhanced mood and emotional resilience [16]

Studies show these benefits can emerge after just 5-20 minutes of practice, with more sustained improvements developing over 4-8 weeks of consistent training [11, 12, 16].

Part 3: Nasal Breathing — Built-In Biochemistry and Mechanics

One of the most fundamental aspects of breathing is how air enters your body. Research shows that breathing through your nose provides significant physiological advantages over mouth breathing [17–22, 24].

The Nasal Advantage

Natural Filtration and Conditioning

The nose is a sophisticated "air-conditioning" system. It filters particulates, warms air to body temperature, and adds moisture—functions the mouth cannot perform [17, 22]. This protects your airways from irritation, infections, and exercise-induced bronchoconstriction [17].

The "Miracle Molecule": Nitric Oxide (NO)

Your paranasal sinuses are a primary production site for nitric oxide (NO), a powerful molecule that mouth breathing bypasses [19]. When you inhale through your nose, you carry this NO into your lungs, where it acts as a potent vasodilator (relaxes blood vessels) and bronchodilator (opens airways). This helps match ventilation (air) with perfusion (blood flow), optimizing oxygen (O2) uptake and protecting against pathogens [19].

Cardiovascular and Autonomic Benefits

A recent study found that just 5 minutes of quiet nasal breathing (compared to mouth breathing) lowers diastolic blood pressure and significantly shifts the nervous system toward a more parasympathetic state, as measured by HRV [21].

Improved Lung Function & Efficiency

The nasal passages introduce substantially greater airflow resistance than the mouth and account for a major share of total airway resistance at rest [22]. This is a feature, not a bug: This resistance naturally slows breathing and creates a mild expiratory backpressure, producing a “PEEP-like” (positive end-expiratory pressure) effect that helps keep small airways open and supports more efficient gas exchange [18, 22]. By stabilizing airflow and improving ventilatory mechanics, nasal breathing has been shown to support healthier lung volumes and oxygenation [18] and to improve ventilatory efficiency during exercise — both in recreational runners trained to use exclusive nasal breathing and in cardiac patients performing aerobic work [20, 24].

How Alveos Uses This

Our approach closes the loop between your body and mind:

We Listen: Our wearable acoustic and mechano-acoustic sensing continuously characterizes your breathing patterns — rate, depth, regularity, and diaphragmatic engagement — with validated accuracy in real-world, continuously monitored settings [1–8].

We Interpret: Changes in breathing pattern reflect shifts in autonomic drive: rapid, shallow, irregular chest-dominant breathing is associated with sympathetic activation (fight-or-flight), while slower, deeper, more regular diaphragmatic breathing is associated with parasympathetic recovery (rest-and-digest). We translate these breathing signatures into an index of physiological load and recovery so you can see, in the moment, how activated or relaxed your system is. This interpretation framework is grounded in established links between breathing behavior, vagal control of the heart, and autonomic balance as indexed by HRV and vagal “brake” function [9–11, 14, 21, 23].

We Guide: We then deliver brief, evidence-based breathing protocols — including slow, diaphragmatic, nasal-dominant breathing at resonance-like rates — that are shown to upregulate parasympathetic activity, increase vagal tone, lower blood pressure, reduce subjective stress, and improve emotional control and cognitive performance [10–16, 21].

We are turning your breath from an unconscious pattern into a conscious, controllable tool for better health.

Last updated: October 2025