Why leaf-blowers set off your nervous system

There’s a good reason why certain sounds make you feel incredibly unsafe or overwhelmed. It’s not just because you’re noise sensitive when you can’t bear the sound of a leaf blower or vacuum cleaner.

Holidays in my old apartment complex were the worst. On public holidays people washed and vacuumed their cars. My neighbour had a side job vacuuming office chairs, and on every major holiday, the high-pitched whine of the vacuum cleaner would go all day. Public holidays at home did not feel safe to my nervous system.

The complexity of the acoustic environment in our contemporary industrial world means it is loaded with low frequency sounds our nervous system is programmed to interpret as a predator, and neuro-sensitive systems are particularly attuned to detecting environmental threats.

If you're neurodivergent, have experienced trauma, and particularly if you're in recovery, your physiological state is already highly attuned to danger. It has been habituated to detecting danger over years of noticing and experiencing danger. It’s what your brain looks for, and what it sees - sometimes this is not objectively accurate.

When your neighbour uses their leaf blower, or you hear a chain saw trimming trees on your street, your sensitive nervous system zooms into sympathetic arousal, making it impossible for the sound to reach your middle ear bones to dampen your fear.

Instead of the noise being mediated through your middle ear bones, the sound vibrates through your jawbone. From your body's perspective, vibrations sensed in your jawbone signal the approach of a predator or a threat - possibly a real-life tiger in the form of a vacuum cleaner coming to suck you up and spit you out. This response originates from prehistoric human biology.

All mammals have the unique characteristic of their middle ear bones being 'detached' from their jawbone, which enables them to hear certain frequencies, especially above background noise. When the middle ear bones are agitated, our body (biology) feels unsafe and is unable to hear frequencies that would help it to feel safe. It is only when the middle ear bones become still again that our body can hear other sounds.

The frequencies that calm our body match the intonation in the human voice. Vocal prosidy has the power to change our physiological state - and in so doing, provide us (and our bodies) with the experience of safety. In a nutshell, the 'right' or ‘perfect’ pitch of voice will make us feel safe.

Often - but not always - it is a perfect match to the intonation of the female voice (but recall the actors Alan Rickman and Richard Burton and you'll know this isn't just a female voice thing). Perfect prosidy is often the same pitch found in a mother's lullaby, or the melody in a symphony. Folk music is a great example, because even though the lyrics could be referring to horrible things, the musicians sing very melodically - and often smile while doing it. Smiling also activates the inner ear bones, which switches on the vagus nerve that mediates social engagement, which can only be turned on when we feel safe.

For those who’ve been living convinced that they are just overly sensitive to all noise, it can be really empowering to understand that it is only a range of frequencies that will trigger this response. Knowing this, you can make choices that allow you to reduce the effects of other stressors proactively so that your dysregulated nervous system has the capacity to cope with environmental noise out of your control.

Read more about neurodiversity here.

Leaf blowers are a common trigger for neuro-sensitive nervous systems

Support for neuro-sensitive healers

In my trauma-informed group program for healers and neuro-sensitive practitioners, I teach methods to eliminate overwhelm and rewire patterns of protection, banish procrastination and self-sabotage and metabolize trauma that's holding back neurodivergent practitioners from thriving. All set within a safe container of shamanic wisdom practices.

Expansion Training for Healers is a 10-week group program for just 12 healers and neuro-sensitives - with plenty of individual support.

Doors are now open for the next round of Expansion Training for Healers, starting Tuesday 9th May, 2023.

If you're curious how healing and expanding your nervous system can help you, book a co-regulation call to explore whether this trauma-informed counselling course is for you.