“Nails on a chalkboard” is a sound that all of us are familiar with. It has become one of the most stereotypical unpleasant sounds. The worst part about nails on a chalkboard is how this sound seems to draw a physical reaction out of the body. Whenever I hear the sound of nails on a chalk board chills creep over me, I cringe, and I shudder. Even thinking about the sound creeps me out. I can only speak for myself, but I’m pretty sure this sound creates the same effect for many others as well. Or maybe I’m just weird, who knows. Regardless of the physical effects, the high pitched screetching sound produced is one that most people do not find pleasant. We all hate this sound. But why? What makes this sound so awful? How can a sound cause the body to cringe? Musicologists Michael Oehler and Christoph Reuter have offered an explanation.
The researchers started their study by having the participants listen to a variety of discomforting sounds and then rating them. Ultimately, the least pleasant sounds ended up being fingernails on a chalkboard and chalk being rubbed on a slate. They then played these top two least pleasing sounds and monitored physical reactions within the participants such as heart rate, blood pressure, and electrical conductivity of the skin. The results showed that the skin conductivity significantly changed when hearing the sounds, which means there really is a physical change (the cringe feeling) caused by nails on a chalkboard.
In the study, the researchers found that the most unpleasant frequencies were found within the range 2000 to 4000 Hz. This frequency range is interesting because it is note excessively high or low. It is a somewhat average frequency range. Many characteristics of human speech are found within this range. The researchers think that the shape of our ear canals may have evolved overtime to amplify sounds within this range in order to help with communication. Unfortunately, the nails on chalk board sound lies within this range and therefore also gets amplified. Although this is just speculation, the reason nails on the board sounds so awful may be due to the shape of our ears.
I thought this was a pretty interesting study to read. However, I’m kind of disappointed they didn’t explain what exactly about the sound causes us to cringe. At least I found out that I’m not the only one who physically does not like that sound. Now that its been confirmed that we cringe, I want to know why. I must be something psychological. For me, whenever I hear the sound of nails on a chalkboard I think of what it actually feels like to scratch your nails on a chalk board. The feeling of nails on a chalkboard is almost as bad as the sound. I think the thought of the feeling of scratching the chalkboard is what causes people to cringe. However, I’m not equipped enough to test that hypothesis nor do I really want to. Hopefully someone else comes out with some new research soon to close up some of the loose ends.