Studies have shown that the sound of nails rubbing against wood has the same frequency as a crying baby and a human scream. the urge to survive He says he woke up.

This means that, according to the researchers, some people naturally use this frequency. to their discomfort can cause. Studies on this subject speak of some very interesting things. Come on, let’s see what science has to say.

In fact, our ears are naturally programmed to be disturbed by certain sound frequencies.

In a 1986 study, someone wrote on the blackboard with chalk. nails rubbing the wood and recording the sound of this rubbing being received. Researchers want to artificially extract frequencies of these sounds other than their own and test why people feel uncomfortable with them. By having people listen to these sounds, the researchers asked people to rate how uncomfortable they were.

Even if the academics deleted the highest frequency recording and continued to listen to the rest, the participants still found the sounds disturbing. This time your voice is medium and in the low spectrum By removing frequencies (in the range), the experts noted that interestingly, subjects rated sounds more positively.

Michael Oehler and Christoph Reuter, who work in musicology, discovered in their 2011 research that the sound frequencies that disturb people the most are. 2000 and 4000 Hz (frequency unit). Because people felt the loudest volume in these ranges. In this study of 24 people, the researchers randomly had each of the participants listen to eight sounds and asked them to rate the sounds based on the sounds they liked or most bothered.

Of course, the researchers also measured the participants’ skin conductance (the level of skin electrification after sweat secretion), heart rate, and respiration while the participants listened to these recordings. The purpose of this is: taking into account physiological reactions they want to come to a conclusion. The interesting thing is that each of these eight sounds is a derivative of the sound of nails rubbing against wood. But there’s something else interesting here…

Being conditioned to the source of the sound is another cause of this discomfort.

Researchers complicate things a little more, discovering who knows the source of the sounds and who doesn’t. two groups of participants separates them. They do this because they want to look at what could be causing the situation from a psychological point of view. While one group knows that these sounds are made by rubbing nails against wood, the other group thinks it is an edited version of a piece of music.

However, the researchers found that the participants’ physical response to sound was not that different. The really different result came from knowing the source of the sound. Those who knew the sound of nails rubbing against the wood judged the sounds negatively. For example, those who thought it was a musical composition liked the sound more. So the source of the sound being mentally conditioned It is also a factor in the difference in results.

The sharp and rough sound also makes it unappealing.

Professor John McDermott, who works in this field, discovered in his 2012 research that a sound has two sides that don’t sound right to our ears. One is the sharpness of the sound due to the high frequency and the roughness caused by the fluctuation caused by the frequency density. But the academic says that people often suffer from erratic noises. So let’s say you rubbed your nails on wood, here’s what happens. Since the sound will be rough, it is natural that you cannot tolerate this sound. In short, we can say that these two aspects are more effective than the frequency of the sound.

Sources: Live Science, Popular Science