Brown noise had its moment a few years ago: hours-long videos, millions of views, and a lot of people saying it finally let them concentrate. Some of that is probably real. Much of what gets said about it, especially that it “calms the ADHD brain”, runs well ahead of the evidence. This guide separates what is known from what is hopeful, and explains how to use steady noise in a way that is likely to help.
What the colors mean
“Colored” noise describes how a sound’s energy is spread across frequencies.
- White noise has equal energy at every frequency. Each higher octave spans more frequencies, so most of that energy sits in the treble, and it sounds bright and hissy, like static or a detuned radio.
- Pink noise loses energy as the frequency rises, so each octave carries the same amount. It sounds softer and fuller, a bit like steady rain.
- Brown noise (also called Brownian or red noise) drops off faster still, which leaves a deep rumble, like a distant waterfall or strong wind. The name comes from Brownian motion, named after the botanist Robert Brown, not from the color.
All three are steady sounds without rhythm, melody or words. That steadiness is the key to understanding when they help.
The best-supported benefit: masking speech
The clearest case for noise has nothing to do with brainwaves. It is about hiding other sounds, especially conversation.
Speech is the most distracting sound in shared spaces, and research on open-plan offices has found that what matters is how intelligible it is, not how loud. A model published by Valtteri Hongisto in 2005, built from earlier laboratory studies, predicts that performance starts to drop once nearby speech becomes even partly intelligible, and that most of the damage is done well before it is perfectly clear. That is why offices install sound-masking systems: a steady background hiss makes nearby words harder to make out.
You can do the same thing at home or in a library. If a roommate is on the phone or a café table is chatting next to you, a steady noise at low volume lowers how much of the conversation your brain can follow. White, pink and brown noise all work for this. Rain does too. Which one you prefer is mostly a matter of taste.
White noise and attention: the honest picture
The research that started the “noise helps focus” idea comes from Göran Söderlund and colleagues in Sweden. In a 2007 study, white noise improved memory performance in children with ADHD but made performance worse for children without it. A 2010 follow-up with secondary-school pupils found the same pattern: background white noise helped inattentive students and hurt attentive ones.
The researchers explain this with a theory called the moderate brain arousal model, which proposes that people with lower baseline arousal benefit from extra stimulation. It is an interesting hypothesis, not settled science.
The most useful summary so far is a 2024 meta-analysis led by Joel Nigg. Across 13 studies with 335 young people who had ADHD or high levels of ADHD symptoms, white and pink noise produced a small benefit on laboratory attention tasks. In comparison groups without ADHD, the effect was small and negative. The authors found no studies of brown noise at all.
Healthy adults are a mixed picture. A 2017 study by Anthony Angwin and colleagues found that young adults who heard white noise while learning the names of unfamiliar objects recalled them better than those who learned in silence. Single studies like this need replicating before they mean much.
Put together:
- For people with ADHD or marked attention problems, white or pink noise may give a small boost on some tasks. It is not a treatment, and it is not a replacement for anything a clinician recommends.
- For people without attention problems, noise is at least as likely to hurt slightly as to help.
- For brown noise specifically, there is essentially no controlled evidence yet. Its popularity rests on personal reports.
None of this means brown noise is useless. If you prefer its deep rumble to the hiss of white noise, the masking argument above applies just the same. It just isn’t a proven focus enhancer.
Rain, nature sounds and cafés
Rain is a natural broadband sound, close to pink noise, with some gentle variation. A 2021 review by Rachel Buxton and colleagues pulled together studies on natural sounds and found they were associated with better health outcomes, more positive mood, and lower stress and annoyance. Those studies measure wellbeing more than concentration, but feeling calmer is not a small thing when you have six hours of studying ahead.
For creative work, a moderate level of background noise may help a little. In a series of experiments published in 2012, Ravi Mehta, Rui Zhu and Amar Cheema found that moderate ambient noise (70 decibels) improved performance on creative tasks compared with a quiet 50 decibels, while loud noise (85 decibels) hurt it. That fits the common experience of brainstorming well in a café and reading poorly in one.
The homepage has four looping ambient sounds (rain, café, fireplace and wind) with separate volume sliders. You can layer them under the live music or pause the stream and use a loop on its own. If you want music instead of noise, our article on studying with background music explains what the research says about that.
Binaural beats: contested
Binaural beats play a slightly different tone in each ear, for example 200 Hz on the left and 210 Hz on the right. The brain perceives a third “beat” at the difference, here 10 Hz. Apps claim this can push your brainwaves into a focused state.
The evidence is mixed. A 2019 meta-analysis by Miguel Garcia-Argibay and colleagues pooled 22 studies and reported a medium-sized effect on memory, attention, anxiety and pain. But the usual explanation, that the beats make brain activity synchronize to the beat frequency, has not held up consistently. A 2023 systematic review of EEG studies found that only 5 of 14 reported results in line with that idea, while 8 contradicted it. Binaural beats also only work through headphones. If you enjoy them, there is no harm in trying, but claims about “gamma waves for focus” are not established.
Pink noise and sleep: a lab finding, not an app feature
You may see pink noise sold as a way to improve memory while you sleep. The research behind that is genuinely impressive, but it is narrower than the marketing. In a 2013 study, Hong-Viet Ngo and colleagues played short bursts of sound timed precisely to sleepers’ slow brain waves, using live EEG recordings. Memory consolidation improved, and the same sounds played out of step with the brain waves had no effect.
A pink noise track playing all night is not that. It may help some people fall asleep by masking street noise, which is worth something, but it is not the same as the closed-loop stimulation studied in the lab.
How to use noise sensibly
- Use it to mask, not to motivate. Steady noise is most useful when there is speech or unpredictable noise around you.
- Keep it quiet. Set it just loud enough to blur the background. If you can’t hear someone talking to you at arm’s length, it’s too loud, and long sessions at high volume are bad for your hearing.
- Match it to the task. Noise or café sounds may suit brainstorming and routine work. Difficult reading and memorizing usually go better in quiet.
- Test it. Try a week of sessions with noise and a week without, and measure something concrete, such as practice questions answered correctly. Whether you feel focused is a poor guide.
- Consider silence first. Earplugs or noise-canceling headphones without any sound playing are an underrated option, and for most people without attention difficulties they are the safest bet.
If you’re putting together a full study setup, our guide to building a calm study space covers lighting, layout and other ways to reduce noise in a room.
Sources
- Hongisto, V. (2005). A model predicting the effect of speech of varying intelligibility on work performance. Indoor Air, 15(6), 458–468.
- Söderlund, G., Sikström, S., & Smart, A. (2007). Listen to the noise: Noise is beneficial for cognitive performance in ADHD. Journal of Child Psychology and Psychiatry, 48(8), 840–847.
- Söderlund, G. B. W., Sikström, S., Loftesnes, J. M., & Sonuga-Barke, E. J. (2010). The effects of background white noise on memory performance in inattentive school children. Behavioral and Brain Functions, 6, 55.
- Nigg, J. T., Bruton, A., Kozlowski, M. B., Johnstone, J. M., & Karalunas, S. L. (2024). Systematic review and meta-analysis: Do white noise or pink noise help with task performance in youth with attention-deficit/hyperactivity disorder or with elevated attention problems? Journal of the American Academy of Child & Adolescent Psychiatry, 63(8), 778–788.
- Angwin, A. J., Wilson, W. J., Arnott, W. L., Signorini, A., Barry, R. J., & Copland, D. A. (2017). White noise enhances new-word learning in healthy adults. Scientific Reports, 7, 13045.
- Buxton, R. T., Pearson, A. L., Allou, C., Fristrup, K., & Wittemyer, G. (2021). A synthesis of health benefits of natural sounds and their distribution in national parks. Proceedings of the National Academy of Sciences, 118(14), e2013097118.
- Mehta, R., Zhu, R., & Cheema, A. (2012). Is noise always bad? Exploring the effects of ambient noise on creative cognition. Journal of Consumer Research, 39(4), 784–799.
- Garcia-Argibay, M., Santed, M. A., & Reales, J. M. (2019). Efficacy of binaural auditory beats in cognition, anxiety, and pain perception: A meta-analysis. Psychological Research, 83(2), 357–372.
- Ingendoh, R. M., Posny, E. S., & Heine, A. (2023). Binaural beats to entrain the brain? A systematic review of the effects of binaural beat stimulation on brain oscillatory activity. PLOS ONE, 18(5), e0286023.
- Ngo, H.-V. V., Martinetz, T., Born, J., & Mölle, M. (2013). Auditory closed-loop stimulation of the sleep slow oscillation enhances memory. Neuron, 78(3), 545–553.
