Blog #4: Research Round 2

Inquiry Question: How does the brain relate to hearing and why do certain sounds make our skin “crawl”?

Round 2 Research: What is the “skin crawling” feeling? How is it generated? What is the process in our body that makes us feel this way?

• The amygdala adjusts the response of the auditory cortex when we hear an unpleasant noise (Pedersen, 2012).
• • Heightens activity and triggers a negative emotion reaction.
  • Amygdala: processes emotions; auditory cortex: processes sound
• Experiment in watching the brains of 13 participants using functional magnetic resonance imaging (fMRI) (Petersen, 2012):
  • Volunteers rated sounds from most unpleasant to most pleasing: the sound of a knife on a bottle to babbling water.
  • The findings demonstrated that the activity of the amygdale and the auditory cortex are directly correlated with the negative ratings given by the participants.
• The amygdala, the emotional part of the brain, controls the activity of the auditory part of the brain, which makes us more sensitive to unpleasant noises than soothing noises like a babbling brook (Petersen, 2012).
• Sounds in the frequency range of approximately 2000-5000Hz is perceived as unpleasant (Petersen, 2012).
• Medical conditions can be better understood when we grasp a better understanding of the brain’s reaction to noises (Petersen, 2012).
  • Hyperacusis: decreased sound tolerance
  • Misophonia: hatred of sound
  • Autism: sentivity to noise
• Emotions disorders and disorders like tinnitus and migraine may also be looked at further in relation to the interaction of the amygdala and the auditory cortex (Petersen, 2012).
  • These disorders heightened perception of unpleasant aspects of sounds.
• Macaque monkeys: similarities between reactions to disturbing sounds (Green, 2016).
  • Suggesting that human’s strong dislike for certain sounds may be left over from an ancient reflex.
  • Not proven.
• Our strong dislike and triggering feeling for certain sounds might be due to that we are remembering the image, or imagining the feeling (Green, 2016).
  • Only one study. Possible that results would be different in other species.
• 2012 study out of Newcastle University (Green, 2016):
  • Subjected 16 people to 74 different sounds.
  • Top 10 raked more irritating sounds:
    • Knife on bottle
    • Fork on glass
    • Chalk on blackboard
    • Ruler on bottle
    • Nails on blackboard
    • Female scream
    • An angle grinder
    • Squealing breaks on a bicycle
    • A baby crying
    • An electric drill
  • The above sounds fell in the 2000-5000Hz.
• MRI machine showed which brain part lit up in response to the irritating sounds (Green, 2016).
  • Researchers found strong connection between the auditory cortex (processes sound) and the amygdala (involves emotion).
• When we hear irritating noises, it is likely that the amygdala affects how the auditory cortex responds to the sounds, making it more sensitive and causing an unpleasant emotional reaction (Green, 2016).
• Our amygdala may be taking charge when we hear awful sounds, making the auditory part of the brain to process the sound much more intensely (Green, 2016).
• Other scientists believe that the anatomy of the ear amplifies certain frequencies to the point that they cause real, physical discomfort (Green, 2016).
• Misophonia, aka selective sound sensitivity syndrome: a strong dislike or hatred of specific sounds (WebMD Editorial Contributors, 2020).
  • Emotional or physiological responses are triggered by sounds unreasonably given the circumstance.
  • Reaction can range from anger, annoyance, panic, and the need to flee.
• There is a different between having a “skin crawling” sensation due to a sound and misophonia.
  • Triggering noises with misophonia can be eating, breathing, chewing sounds (WebMD Editorial Contributors, 2020).
  • The sounds can also be keyboard or finger tapping, windshield wipers, fidgeting sounds, etc.
  • Sounds are often repetitive (WebMD Editorial Contributors, 2020).
• Misophonia is currently not considered a diagnosable condition. However, investigators and researchers argue that misophonia should be regarded as a new mental disorder as it causes intense emotions (Taylor, 2017).
• This “skin scratching” sensation when we hear certain sounds may be considered as an emotion, just that in English, there is not a word for it (Tijou, 2017).
  • “Grima”, a Spanish word, is a word to describe the sound of fingernails on a chalkboard, or a knife scratching a plate.
  • Spanish speakers described this word as an “unpleasant sensation,” “shivering,” “sounds,” and “repulsion.”
• People’s perception of sounds may play a role in how irritating it is (Warner, 2011).
• In an experiment (Warner, 2011):
  • Half of the participants were told they were listening to contemporary music.
  • Other half of the participants were told they were listening to the sound of fingernails on a chalkboard.
  • People who were aware about listening to fingernails scratching a chalkboard rated the sound as more unpleasant and were more stressed (based on stress responses like blood pressure and sweat).
• Not only sharp sounds like knife scratching glass and nails scratching chalkboard can trigger us. Sounds like baby crying, dogs barking, and car response can also trigger a response of irritation. This is due to their repetitive and loud sound (Yorkshire Times, 2022).

References

Green, H. [SciShow]. (2016, March 10). Why do some noises make you cringe [Video]. Youtube. https://www.youtube.com/watch?v=re0PaEEbPVE

Pedersen, T. (2012, October 11). Why we cringe at unpleasant sounds. Psych Central. Retrieved September 30, 2022, from https://psychcentral.com/news/2012/10/11/why-we-cringe-at-unpleasant-sounds#4

Taylor, S. (2017, June). Misophonia: A new mental disorder? Medical hypotheses. Retrieved November 5, 2022, from https://pubmed.ncbi.nlm.nih.gov/28571795/

Tijou, S. (2017, March 2). There’s now a word for nails on a blackboard – but it’s not in English. BBC News. Retrieved November 5, 2022, from https://www.bbc.com/news/newsbeat-39141780

Warner, J. (2011, November 4). Why the sound of fingernails on a chalkboard irks you. WebMD. Retrieved November 5, 2022, from https://www.webmd.com/balance/news/20111104/why-fingernails-on-a-chalkboard-irks-you

WebMD Editorial Contributors. (2020, December 13). What is Misophonia? WebMD. Retrieved September 30, 2022, from https://www.webmd.com/mental-health/what-is-misophonia

Yorkshire Times. (2022, October 26). Why certain sounds annoy us and why? Yorkshire Times. Retrieved November 5, 2022, from https://www.yorkshiretimes.co.uk/article/Why-Certain-Sounds-Annoy-Us-And-Why

My focus in the next round is why do certain sounds make our skin crawl? I am aware that this focus is very similar to my research focus this round, especially after finishing it. Therefore, I will have two pathways to completing my final research round. First, I will link all the information from round one and two together, and research more specific evidence, like experiments that happened over the years, to back up my point. This will allow me to see if there were new discoveries on this question over time, and to conclude an answer to my inquiry question. For my second aspect, I will connect this question to some trends and problems in the society, is this sensation affecting our lives in any way? Specifically, I found out in this research round that the “skin crawling” impression after hearing a triggering sound is related to Misophonia, which is a condition that is not an official diagnosis. The issue is, there are people suffering symptoms from Misophonia. Does the world have a view on this problem? If so, what are we doing, or what are we trying to do to help solve the issue? This will allow me to connect this inquiry question to the world and develop a more well-rounded answer.