White noise is a kind of acoustic noise with a completely flat spectrum, but what does it mean in practice? What exactly hides behind this vague term?
In short, white noise is the sequence of monotonous sounds that we hear when surrounded by nature or when we are at home. White noise may be produced by water in a fountain, ocean, or waterfall, but also by a working hairdryer, fridge, ticking clock, or the sound of water drops falling from the tap.
White noise has a soothing effect on human brain, because it enables the brain to simultaneously work and relax.
Since white noise is contained in each human audible frequency, it is often used to mask unwanted sounds. This is especially useful for light sleepers often distracted by sudden noises. White noise drowns out all other sounds that interfere with peaceful sleep, or falling asleep. An additional advantage of white noise is that it stimulates the brain thus satisfying the need for stimulation even at a time when the brain is most active. A study conducted by Swedish scientists, Sikström, Loftesnes and Sonuga-Barke, on 51 students showed that children who usually have trouble concentrating, would improve their memory when exposed to white noise, which could benefit their school performance.
White noise also positively affects concentration in situations when people are exposed to chaotic sounds, such as other people’s conversation or noise pollution coming from a busy street. Annoying external sounds may contribute to rising stress levels and consequently elevate blood pressure or cause chronic headaches.
White noise, especially in the form of nature sounds, for example a recording of the sound of the ocean or falling waterfall, relaxes and reduces stress. The soothing effect of these sounds can be linked to the thumping sound blood makes when a fetus is in a mother’s womb. Thus for a newborn, white noise is more natural than silence, and it may prevent sudden or loud noises from disrupting a baby’s sleep. White noise also may help to prolong a baby’s sleep, giving parents some respite.