White noise machines have become popular. And it is not for less since they guarantee a restful sleep, becoming a natural alternative to sleeping pills, although their functions go much further and some types can even be used to practice relaxation or improve concentration. However, before purchasing a white noise generator, it is important that you know how it works and, above all, the damage that a white noise generator for sleeping can cause if exceeds the recommended decibels.
What is white noise?
White noise is a sound signal that contains all frequencies, of the same power. Basically, with the white noise the auditory threshold reaches its maximum speed; that is, when we hear that background sound, the rest of the auditory stimuli lose their power and in many cases they fail to activate the cerebral cortex while we sleep. In this sense, we could say that the white noise is like a “sonic wall”; it stops or reduces the rest of the sounds.
For example, if we open a window in a high-rise building, below we will simultaneously hear hundreds of noises. The sound of the cars, the music of the commercial premises, the voices of the people and the working machines… However, since we are far away, none of those sounds prevails over the others, so that we only hear a dull rumor. White noise machines do just that.
White noise for sleeping
To understand how white noise works, we must keep in mind that our brain can only interpret a certain number of sounds at the same time. That is why, when it captures the enormous amount of sounds coming from the white noise, it interprets them like something distant.
Since the ear is one of the senses that keep functioning while we sleep, to alert us of any risk in the middle of the night, the sounds that occur around us can affect the quality of sleep or even wake us up.
In fact, a study conducted at the Manchester Metropolitan University found that there is a link between night noises and nightmares. Sleeping problems have also been linked to the onset of neurodegenerative diseases such as Alzheimer’s, because the brain cannot rest enough.
To make things worse, the poor quality of sleep has also been linked to cardiovascular problems. A very interesting study carried out at the University of Pennsylvania, revealed that although we apparently get used to certain noises, after a period of time, since these cause less changes in brain waves, they continue to affect the heart rate, producing states of excitement.
Of course, all people do not respond in the same way to noise. Researchers from Harvard University discovered that brain rhythms are crucial in our ability to tolerate noise. In a general sense, noise is more likely to awaken us during the second stage of sleep, the non-REM light cycle. Children and the elderly are more vulnerable to interruptions caused by noise.
White noise machines for sleeping help to avoid any sudden interruption of sound coming from the environment and, therefore, decrease the frequent awakenings throughout the night.
White sound generators also improve attention and memory
Science is just beginning to investigate the effects of white noise. Researchers at the University Medical Center Hamburg-Eppendorf discovered that listening to soft noise improves memory. In this experiment, a group of people heard noise and another white noise, while they underwent a brain scan and a memory test.
They discovered that the white noise was acting at the level of the mesolimbic mesencephalon, a region of the brain related to the pathway of dopamine, a neurotransmitter. This means that white noise improves connectivity between the brain regions associated with dopamine modulation and attention, which results in improved memory.
In fact, it is not the first study that points out that white noise enhances cognitive functions and learning. Researchers from the University of Queensland found that listening to white noise while trying to memorize something improves our ability to later remember that information.
Do white noise machines have contraindications?
Experts say that white noise is safe, even for children. However, they also indicate that it is important to buy the best white noise machine available because it must have an adequate volume regulator.
If the volume is too high, it can cause damage. Keep in mind that we have a limited number of ciliated cells, approximately 10,000, which are responsible for capturing the sound. These cells receive the high frequency sounds and with aging they start to fail.
Actually, the problem is not the white noise but the decibels that white noise machines can reach. An otolaryngologist from The Hospital for Sick Children in Toronto, analyzed 14 white sound generators at three different distances: 30 centimeters, which means placing the white noise machine in a baby’s crib; at 100 cm, placing it on a bedside table next to the crib; and at 200 cm, at the end of the room.
The standards for auditory health indicate that above 85 decibels, adults can begin to suffer from hearing loss. When the white noise devices were placed at 30 cm, some emitted more than 85 decibels. This means that, if you want to buy a white noise machine, you better look at that detail and do not place it too close to your bed at bedtime.
What is the best white noise machine for sleeping safely?
There is a wide variety of white noise machines, but not all fulfill their function. However, first you must know that there are two types of white noise machines: mechanical and electronic.
Mechanical white noise machines have a small fan to generate the sound and generally have several switches that serve to adjust the air input into the machine itself. This way you can change the volume of the sound. The mechanical white noise generators have the advantage that they produce a continuous noise, but their volume is not adjustable, so they are not usually the best option.
The electronic white noise machines generate two types of sounds: a synthetic and continuous noise and pre-recorded noises of continuous cycle. The most modern models include different types of sounds, so they are much more versatile. Some have a small “defect” because when repeating the sound, there is a barely perceptible jump that breaks the continuity.
Since Sleep easy sound conditioners are generally used for sleeping, concentrating or relaxing, it is important that you look at three essential details:
– That the sound is in high fidelity, when you cannot concentrate or sleep, the poor quality of the sound will become an additional factor of frustration.
– That has a volume regulator, so that the excess of decibels does not harm you. Older sound generators do not usually have it.
– That can be programmed for a long time, some of the white noise machines for sleeping turn off themselves after 120 minutes, so they do not stay on all night.
The Sound + Sleep machine is simply perfect as it allows you to camouflage ambient noises and relax, as well as having other very convenient functions, so that right now it is the best option considering its quality / price.
– Not only does it have white noise, but it generates 30 enveloping sound atmospheres that facilitate sleep, relaxation or simply cover other sounds. It has the sounds of the waves of the sea, the crackling of the wood in the fireplace, the sound of a waterfall or running water and even has a special sound for meditation, so you can use it to practice yoga or mindfulness.
– This white noise machine not only has a volume regulator, but it goes a step further because it listens to the environment and responds automatically by adapting the volume, so you don’t have to worry about anything.
– It has a timer that you can regulate so that the volume goes down delicately after 30, 60, 90 or 120 minutes to facilitate the passage to sleep. In fact, its front panel also dims automatically for easy resting.
Angwin, A. J. et. Al. (2017) White noise enhances new-word learning in healthy adults. Nature Scientific Reports; 7:13045.
Raush, V. H. et. Al. (2014) White Noise Improves Learning by Modulating Activity in Dopaminergic Midbrain Regions and Right Superior Temporal Sulcus. Journal of Cognitive Neuroscience; 26(7):1469-1480.
Hume, K. I. et. Al. (2012) Effects of environmental noise on sleep. Noise Health; 14(61): 297-302.
Basner, M. et. Al. (2011) Single and Combined Effects of Air, Road, and Rail Traffic Noise on Sleep and Recuperation. Sleep; 34(1): 11-23.
Dang-Vu, T. et. Al. (2010) Spontaneous brain rhythms predict sleep stability in the face of noise. Current Biology; 20(15): 626–627.