Brown noise: What is it and what is behind its hypnotic effect?

Nowadays, thousands of people use white noise or Lo-Fi music to concentrate while they work or study. These types of sounds, they point out, help them regain control of their attention, tuning out the hundreds of stimuli that compete for it throughout the day.

Another useful tool is brown noise. Writer Zadie Smith claims that she listens to it day and night: “I would only manage to concentrate in coffee shops. When I was poor and couldn’t afford to go to a coffee shop, I tried finding coffee shop sounds on YouTube, and then I found something called ‘brown noise for concentration.’ Ever since, I use it every time my mind is all over the place and I need to get work done.”

Brown noises are very popular among TikTok’s ADHD community. This community is responsible for the recent popularity of these sounds, which grows every day. Brown noise is a natural sound, more pleasant for the human ear than white noise (better known and studied). It could be the sound of a waterfall, heavy rain or a large river. It might also evoke a distant roar. It contains all the frequencies of the spectrum, but places more emphasis on the low ones, so it is more perceived as nice and relaxing than sharp or irritating.

The term “brown noise” has nothing to do with color. It refers to the sound of Brownian motion, identified in 1827 by botanist Robert Brown. Technically, it is a version of white noise with the low-frequency notes augmented and the less pleasant (and more distracting) high-frequency notes turned down; this counteracts the human ear’s tendency to hear the high frequencies louder.

There are hundreds of brown noise playlists on Spotify, classified according to their purpose. You can find playlists for study, for concentration, for putting babies to sleep, for meditation or for deep sleep. If you do an exercise — maybe you can play one of those playlists to finish reading this story — the first evidence you will notice is that this sound blocks others that used to make you get up from your desk. Some experts do not rule out the placebo effect. The feeling is that of being isolated in the cabin of an airplane, enveloped by a constant but calm noise.

White noise has been used since the 1960s to improve the quality of sleep and some cognitive tasks in children with ADHD, benefits that have been proven in several clinical trials. As for brown noise, a team from Regis University, in Colorado, showed that it did not actually produce any new effects compared to those already seen with white noise, regardless of the popularity it has gained in recent times. On TikTok, the hashtag #brownnoise has over 86 million views, with the most successful videos showing people with ADHD filming themselves reacting to brown noise. Many claim that their brains never felt more comfortable.

TikTok users talk about brown noise as a heavenly sound that has the nearly magical attribute of blanking your mind. Although science has not been able to prove it, some scientists do believe that an overwhelmed brain can be relieved by an external sound that blocks out the noise of a ruminative thought.

Researchers from Regis University point out that the therapeutic effects of full-spectrum noise — be it white, brown, or even purple — have only been proven at high decibels. That is why they believe that those who feel that low-level background brown noise helps them relax, focus or sleep, may be benefiting from a sound masking effect; that is, a pleasant sound that blocks other more intrusive and irritating ones.

A few months ago, YouTube suspended the streaming music channel Lofi Girl, which had been playing non-stop for more than 20,843 hours; a little over two years. The measure was related to a copyright issue that later turned out to be false. But why was Lofi Girl such a popular channel? The explanation, again, has to do with concentration — or, rather, the lack of it.

Lofi Girl works as a non-stop stream of lofi music. The beats are smooth hip hop with no vocals, optimized for calm and focus. The channel is illustrated with a video of a girl who is highly focused, working on her desk. As the day goes on, the scenery changes, a cat wags its tail and Lofi Girl continues to write at a steady pace set by the music. The promise is precisely that: music that provides absolute concentration to work.

This phenomenon has been studied at the University of London. In her article Beats to Relax/Study To: Contradiction and Paradox in Lofi Hip Hop, ethnomusicologist Emma Winston observes that channels like Lofi Girl are appealing because they offer productivity and relaxation, topped with “a vague, abstract longing for a past which the listener is fully aware never existed.” There is no pressure to socialize, although in a side window you can leave your ideas and comments, and also receive responses.

“It is experienced alone, but used as a means of interpersonal care and connection,” writes Winston, who considers it one of the great paradoxes of lofi music: it is a genre created for those who seek peace, but not silence. Another contradiction is how this channel managed to skip all the commercial mechanisms that support the internet business, because its continuous reproduction prevents YouTube from offering advertising or content that would probably take the user out of their auditory nirvana.

The popularity of noise and music for concentration holds a mirror up to today’s society: we fear emptiness, and we are only able to disconnect if we can connect to something else.

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