Noise to Soothe Your Mind
-Written by Dr. Anjali Mediboina, House Surgeon, ASRAM
A recent Instagram reel brought to my attention “brown noise”, noise which apparently works wonders for people with anxiety, and especially helps those who have trouble falling asleep (Alexa, play Sleepless in by Epik High).
Now, I was a bit confused, because isn’t that what white noise is? So, naturally, I googled it and it turns out, white noise and brown noise are two different things and, get this, there’s also pink noise. So much noise, all for the sake of soothing the mind!
According to Wikipedia:
(Disclaimer: There was a lot of physics involved, most of which went over my head, but I tried to sum it all up as best as I could)
White noise is basically the static sound you hear when you flip between the stations in the FM. This noise has a lot of uses; in the music industry, white noise is used to create the percussion sounds, like cymbals and snare drums. In medicine, white noise machines are used to mask tinnitus and as a sleep aid.
An interesting thing to note is that studies by Söderlund et al. and Pickens et al. have shown that white noise has benefitted children with ADHD by improving their cognition and concentration. However, the same white noise appears to have negative effects on neurological health and cognition, based on studies by Bigelow et al. and Loewen et al.
Pink noise has equal energy in each octave of frequency, unlike white noise, which has equal energy at all frequencies. Now while I didn’t really understand this sentence, I did understand that pink noise is very cool-first of all, you can use it to test a wide range of audio products, like loudspeakers and microphones. Pink noise is also like the Shreya Ghoshal of the music industry; super versatile, and can be used to create almost any type of sound.
And the coolest thing of all: it also occurs in nature! Our heartbeat rhythms, firing of single neurons and the rise and fall of tide heights are common examples of pink noise. According to studies by Zhou et al. and Suzuki et al., this color of noise lowers brain activity, thus leading to stable sleep. A study by Hatayama et al. also showed that pink noise could play a role in enhancing memory.
And last, but not the least, we also have Brown noise, or also known as red noise. A fun fact for you: while white and pink noise are named so for their place on the visible light spectrum, Brown noise is named after the scientist Robert Brown, because this noise is produced by Brownian motion (ya know, the random movement of particles in light or water).
Brown noise is the sound of heavy rain or waterfalls, and has a ‘softer’ quality when compared to white and pink noise. Unfortunately, I couldn’t find any research articles on its effects on focus and sleep, but I have seen many users on YouTube and Instagram praising the better sleep quality and calming effects they get by using brown noise over white noise.
As someone with anxiety, I did feel brown noise is a bit more soothing than white and pink noise, but that’s just a personal opinion. I think the takeaway here is, whatever works for you is best. Just try not to exceed 70dB sound levels, at the risk of damaging your hearing 🙂
1. White noise [Internet]. Available from: https://en.wikipedia.org/wiki/White_noise
2. Söderlund GB, Sikström S, Loftesnes JM, Sonuga-Barke EJ. The effects of background white noise on memory performance in inattentive school children. Behavioral and brain functions. 2010 Dec;6(1):1-0.
3. Pickens TA, Khan SP, Berlau DJ. White noise as a possible therapeutic option for children with ADHD. Complementary Therapies in Medicine. 2019 Feb 1;42:151-5.
4. Attarha M, Bigelow J, Merzenich MM. Unintended consequences of white noise therapy for tinnitus—otolaryngology’s cobra effect: a review. JAMA Otolaryngology–Head & Neck Surgery. 2018 Oct 1;144(10):938-43.
5. Loewen LJ, Suedfeld P. Cognitive and arousal effects of masking office noise. Environment and Behavior. 1992 May;24(3):381-95.
6. Pink Noise [Internet]. Available from: https://en.wikipedia.org/wiki/Pink_noise
7. Zhou J, Liu D, Li X, Ma J, Zhang J, Fang J. Pink noise: effect on complexity synchronization of brain activity and sleep consolidation. Journal of theoretical biology. 2012 Aug 7;306:68-72.
8. Suzuki S, Kawada T, Ogawa M, Aoki S. Sleep deepening effect of steady pink noise. Journal of sound and vibration. 1991 Dec 22;151(3):407-14.
9. Hatayama A, Matsubara A, Nakashima S, Nishifuji S. Effect of Pink Noise on EEG and Memory Performance in Memory Task. In2021 IEEE 10th Global Conference on Consumer Electronics (GCCE) 2021 Oct 12 (pp. 238-241). IEEE.
10. Brownian noise [Internet]. Available from: https://en.wikipedia.org/wiki/Brownian_noise