We perceive noise as something unpleasant and irritating, something that needs to be escaped. It is generally thought of as a distraction or something that overwhelms our senses, inducing stress and headaches. But what if not all noise is unpleasant? What if certain kinds of noise could do the opposite?
Although the general population might think of noise as repulsive, there are some types of noise that can soothe the mind. These kinds of noises, known as white, brown and pink noise, are said to have a calming effect on the mind, easing anxiety and even sometimes improving sleep.
These noises are often played in the background, and their effects on the brain are soothing for some. A systematic review and meta-analysis study published by the National Institute of Health mentioned that the three types of noises are at different frequencies.
White noise has sounds of all frequencies but with equal intensity; brown noise and pink noise have sounds at lower frequencies and less high frequencies. Each noise affects the mind in its own way.
White noise, perhaps, is the most familiar and well-known. It contains all frequencies at equal intensity. It may sound like TV static, a radio, a fan and even a vacuum cleaner, and works by masking out high-pitched and sharp noises.
Pink noise is known to be natural and contains sounds of lower frequencies, often sounding like rainfall, ocean waves, rustling leaves, etc. It can also mask background noise, like distant traffic.
Lastly, brown noise contains sounds of the lowest frequencies than the other two and can sound naturally like distant thunder, storms and strong waterfalls. It can mask lower-frequency sounds well.
According to Northwestern Medicine, a healthcare system of Northwestern University in Chicago, Illinois, each of these types of noise is best for different concerns.
White noise is best for those who need to relax, focus, or are light sleepers.
Pink noise works best for those who have trouble getting deeper sleep, find white noise harsh, or have memory problems, as it can help cognitive performance.
Lastly, brown noise is more effective for those who have anxiety or stress, as well as those who are sensitive to lower-frequency noise or find white and pink noise harsh.
These noises have been said to be excellent tools to help improve the time needed to fall asleep, the quality of sleep, focus and memory. But it is also necessary to adjust the volume and placement of where the sound is playing, as it could disrupt sleep and have the opposite effect.
“When using continuous background noise, it is important to keep the volume just low enough to be audible, but not so high that it would cause arousal from sleep,” said Dr. Malkani, a neurologist and Sleep Medicine physician at Northwestern Medicine.
Another study from the University of Pennsylvania Perelman School of Medicine suggested that these noises can actually disrupt REM sleep, especially in children whose brains are still developing.
Rapid Eye Movement stage, or REM sleep, is when our brains are active, we have dreams and our bodies are paralyzed. This stage is very important for memory consolidation, emotional regulation and brain development. Long-term use of these noises can disrupt it and reduce REM sleep, which might be harmful to the brain.
However, if these noises are your preferred way, then it is advised that you adjust the settings of their intensity, duration and placement.
According to Dr. Mathias Basner, a sleep researcher and professor at PSOM, “I would recommend that if somebody wants to use pink noise, they should do it at the lowest sound level that still works for them.” He continued, “And if falling asleep is the main problem, put the machine/app on a timer so that it shuts off after the subject falls asleep.”
In the end, not all noise is unpleasant. Some can be quite the opposite. However, utilizing them in a safe, recommended manner is very important to improve cognitive function, life and even sleep quality.
