Three Things You Can Do Right Now to Help Regulate Your Nervous System

When stress hits, it doesn't stay in your mind, it shows up in your chest, your breath, your jaw, your gut. That's because your autonomic nervous system, the part of your body that governs fight-or-flight and rest-and-digest states, doesn't wait for you to think your way out of a stress response. It reacts first.

Fortunately, that same physiology gives us a direct way back in. Below are three research-backed techniques you can use in the moment, each targeting the autonomic nervous system through a different pathway: breath, temperature, and sound.

1. Try a Physiological Sigh (Double Inhale, Long Exhale)

The physiological sigh is a naturally occurring reflex, the kind of breath your body does on its own during sleep or after crying, that can also be triggered voluntarily. It involves two inhales through the nose (the second one shorter, "topping off" the lungs) followed by one long, slow exhale through the mouth.

In a randomized controlled trial, Balban et al. (2023) compared daily five-minute sessions of cyclic sighing against box breathing, cyclic hyperventilation, and mindfulness meditation over the course of a month. Cyclic sighing produced the greatest improvement in mood and the largest reduction in respiratory rate of the four conditions tested. The extended exhale is thought to shift the balance of the autonomic nervous system away from sympathetic (fight-or-flight) activation and toward parasympathetic (rest-and-digest) dominance, which is why the effect can be felt within seconds rather than requiring extended practice.

How to do it: Inhale through your nose until your lungs feel full, then take one more short, sharp inhale on top of that. Exhale slowly and completely through your mouth. Repeat for one to three cycles for an acute stress spike, or continue for a few minutes for a longer mood reset.

2. Splash Cold Water on Your Face

Cold exposure to the face activates what's known as the mammalian dive reflex, a physiological response that has been studied for decades in the context of diving physiology and, more recently, for its calming effects on the nervous system. Cold water contacting the forehead, temples, and area around the eyes stimulates the trigeminal nerve, which has direct connections to the vagus nerve and brainstem.

Kinoshita et al. (2006) tested this directly: eight healthy volunteers immersed their faces in water at varying temperatures, with and without breath-holding, while heart rate variability was measured using wavelet transformation. Cold-water immersion produced a significantly greater increase in vagally mediated heart rate variability than warm water or room-temperature conditions, and this effect held even when breath-holding and body position were controlled for — indicating that the cold stimulus itself, not just holding one's breath, is what drives the parasympathetic response.

How to do it: Fill a sink or bowl with cold water, or hold a cold, wet washcloth or ice pack to your forehead, temples, and the sides of your neck for 30 seconds to a minute. This is a particularly useful tool when a feeling is too activated for breathwork alone to reach.

3. Hum, Chant, or Sing

The vagus nerve travels through the throat, and the muscles that vibrate when you hum, sing, or chant sit directly along its path. This is the physiological basis of practices like Bhramari pranayama ("humming bee breath"), a yogic technique that involves producing a sustained hum on the exhale.

In a study using continuous heart monitoring, Trivedi et al. (2023) compared heart rate variability during humming, physical activity, emotional stress, and sleep in the same participants. Humming produced the lowest stress index of the four conditions and was associated with favorable changes in other heart rate variability markers linked to reduced sympathetic activity — meaning that, physiologically, a few minutes of humming outperformed even sleep on this particular stress marker.

How to do it: Close your mouth, relax your jaw, and hum a low, steady tone on each exhale for one to two minutes. You don't need to follow a specific pitch or pattern, the vibration itself is the mechanism, not the melody.

None of these tools requires special equipment, a quiet room, or extended practice to have an effect. When the nervous system is activated, we need entry points that work with the body rather than tools that require calm, clear thinking to execute first. Breath, temperature, and vibration are three separate doors into the same system, and having more than one option means you're more likely to have one available when you actually need it.

As with any self-regulation tool, these techniques are meant to complement, not replace, working with a therapist when stress, anxiety, or nervous system dysregulation are having a significant impact on your life.

If you are feeling overwhelmed and struggling to regulate your emotions, we are here to help! Please reach out to a licensed therapist on our team.

References

Balban, M. Y., Neri, E., Kogon, M. M., Weed, L., Nouriani, B., Jo, B., Holl, G., Zeitzer, J. M., Spiegel, D., & Huberman, A. D. (2023). Brief structured respiration practices enhance mood and reduce physiological arousal. Cell Reports Medicine, 4(1), Article 100895. https://doi.org/10.1016/j.xcrm.2022.100895

Kinoshita, T., Nagata, S., Baba, R., Kohmoto, T., & Iwagaki, S. (2006). Cold-water face immersion per se elicits cardiac parasympathetic activity. Circulation Journal, 70(6), 773–776. https://doi.org/10.1253/circj.70.773

Trivedi, G. Y., Sharma, K., Saboo, B., Kathirvel, S., Konat, A., Zapadia, V., Prajapati, P. J., Benani, U., Patel, K., & Shah, S. (2023). Humming (simple Bhramari pranayama) as a stress buster: A Holter-based study to analyze heart rate variability (HRV) parameters during Bhramari, physical activity, emotional stress, and sleep. Cureus, 15(4), Article e37527. https://doi.org/10.7759/cureus.37527