White noise generators have become fashionable. It is not strange, as they guarantee restful sleep by becoming a natural alternative to sleeping pills, although their functions go far beyond and some types can also be used to practice relaxation or improve concentration. However, before buying a white noise generator it is important to know how it works and, more importantly, the damage that a sleep noise generator can cause if it exceeds the recommended decibels.
What is white noise?
White noise is a sound signal that contains all frequencies of the same power. Basically, with white noise the hearing threshold reaches its maximum speed; that is, when we hear that background sound, the rest of the auditory stimuli lose power and in many cases fail to activate the cerebral cortex while we sleep. In this sense, we could say that white noise is like a “soundproof wall”, it stops or reduces the rest of the sounds.
For example, if we open a window in a very tall building, we hear hundreds of noises simultaneously from below. The noise of cars, the music of commercial premises, the voices of people, machinery at work… But since we are far away, none of those sounds prevail over the others, so that we only perceive a dull noise. Sleep machines do just that.
White noise for sleeping
To understand how white noise works, we need to keep in mind that our brain can only interpret a certain number of sounds at the same time. That's why, when it captures the huge amount of sounds coming from white noise, it interprets them as something distant.
Since hearing is one of the senses that continues to function while we sleep, to warn us of any potential hazards, the sounds that occur around us can affect the quality of our sleep or even wake us up.
In fact, a study conducted at Manchester's Metropolitan University found that there is a link between night noises and nightmares. Sleep problems have also been linked to the onset of neurodegenerative diseases such as Alzheimer's, because the brain cannot rest enough.
And if that's not enough, poor sleep quality has also been linked to cardiovascular problems. A very interesting study conducted at the University of Pennsylvania revealed that even if after some time we get used to certain noises because they produce less changes in the brain waves, they still affect the heart rate, generating states of excitement.
Of course, not all people respond equally to noise. Harvard University researchers found that brain rhythms are crucial in the ability to tolerate noise. Generally speaking, noise is more likely to wake us up during the second stage of sleep, the light non-REM cycle. Children and the elderly are more vulnerable to interruptions caused by noise.
White noise generators for sleep help to avoid any sudden interruption of the sound coming from the environment and, consequently, reduce the frequent awakenings during the night.
White noise devices also improve attention and memory
Science is starting to study the effects of white noise. Researchers at the University Medical Center Hamburg-Eppendorf found that hearing a slight noise improves memory. In this experiment, a group of people heard generic noises and other white noise as they underwent a brain scan and memory test.
It was thus discovered that white noise acts at the level of the mesolimbic midbrain, a region of the brain related to the pathway of dopamine, a neurotransmitter. This means that white noise improves connectivity between brain regions associated with dopamine modulation and attention, which results in improved memory.
In fact, this isn't the first study to point out that white noise improves cognitive function and learning. Researchers at the University of Queensland have found that hearing white noise while trying to memorize something improves our ability to remember that information later.
Do white noise gners have contraindications?
Experts say white noise is safe, even for children. However, they also indicate that it is important to purchase the best white noise machine available because it must have adequate volume.
If the volume is too loud, it can cause damage. Keep in mind that we have a limited number of hair cells, around 10.000, which are responsible for picking up sound. These cells receive high frequency sounds and with aging reduce their capacity.
In reality, the problem is not white noise, but the decibels that white noise generators can reach. An otolaryngologist at the Toronto Hospital for Sick Children analyzed 14 white noise machines at three different distances: 30 centimeters, which would mean placing the white noise machine in the baby's crib; at 100 cm, which would be like putting it on a bedside table next to the crib; and 200 cm, that is, place it at the end of the room.
Hearing health standards indicate that above 85 decibels adults can begin to suffer from hearing loss. When the white noise devices were placed at 30cm, some emitted over 85 decibels. This means that if you want to buy a white noise generator, it will be best to take note of this detail and not place it too close to the bed at bedtime.
What is the best white noise machine for safe sleep?
There is a wide variety of white noise machines, but not all of them fulfill their function. First you need to know that there are two types of white noise machines: mechanical and electronic.
I mechanical white noise devices they have a small fan to generate the sound and generally have several switches that serve to regulate the entry of air into the machine itself. This way you can change the pitch of the sound. Mechanical white noise generators have the advantage of producing continuous noise, but their volume is not adjustable, so they are not usually the best choice.
Electronic white noise generators generate two types of sounds: firstly, a synthetic and continuous noise and then, pre-recorded sounds in a continuous cycle. The more modern models include different types of sounds, so they are much more versatile. Some have a small "defect", in the repetition of the sound there is a barely perceptible leap that interrupts the continuity.
Since white noise devices are usually used for sleeping, concentrating or relaxing, it is important to keep in mind three essential details:
- That the sound is high fidelity. When you can't concentrate or sleep, poor sound quality will become an added frustration factor.
- They have a volume control. That way the excess decibels won't cause you harm. Older sleep machines usually don't have it.
- That it can be programmed for a long period of time. Some sleep white noise generators turn off after 120 minutes, so you avoid it staying on all night.
The Sound + Sleep machine is simply perfect as it allows you to camouflage environmental noises and relax, as well as having other very convenient functions, so much so that at this moment it is the best option considering its quality / price ratio.
- It not only produces white noise, but generates 30 enveloping sound atmospheres that facilitate sleep, relaxation or simply cover other sounds. It reproduces the sounds of sea waves, the crackling of wood in the fireplace, the sound of a waterfall or running water and also 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 control, but goes a step further because listens to the environment and responds automatically by adjusting the volume, so you don't have to worry about anything.
- It has a timer which you can adjust so that the volume drops gently after 30, 60, 90 or 120 minutes to facilitate the transition to sleep. In fact, even its front panel automatically darkens for easy rest.
