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Medical Fingernails on the chalkboard

  1. Dec 30, 2009 #1
    If the sound of fingernails scratching a chalkboard makes one shudder, how can just reading this post cause many people to do likewise?
  2. jcsd
  3. Dec 30, 2009 #2

    Math Is Hard

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    Triggered mental replay of the experience. Think about biting deeply into a freshly-cut lemon. Doesn't your mouth water a little bit?
  4. Dec 30, 2009 #3


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    When my mouth is dry, I use the trick of imagining biting into a lemon, works every time.
  5. Dec 30, 2009 #4


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    I get the same effect from imagining I am biting into a “dilly Bean” (pickled green beans).
    Sooooooo Good.
    Now I am drooling all over the desk.
  6. Dec 30, 2009 #5
    If only such sensations worked with my diet.
  7. Dec 30, 2009 #6


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    Too bad that thinking about being full doesn't work.
  8. Dec 31, 2009 #7
    I wonder if this is not some kind of 'learned response' - not from the usual experiencial method - as with the lemon bite - but 'learned' as in passed down from authority.

    I recall my parents using that expression, of fingernails on a blackboard, and not understanding it - until I consciously searched for the shivers by actually running my fingernail down a blackboard. It was a long time ago - but I am sure there were no shivers until I was told there should be that physical reaction.
  9. Dec 31, 2009 #8
    Would a "chalkboard" survival instinct occur if one were desperately clawing for dear life while scaling a cliff?
  10. Dec 31, 2009 #9
    That is another facet of the question .... the screech of metal being tore is something that can bring shivers. If I, at home, hear a car accident out side my rooms, the screeching of the metal as it is ripped apart certainly will give me goose bumps. I doubt if the person involved in the incident, even closer than I, will experience the reaction.

    or maybe they will, but are so preoccupied that it is not noticed. :confused:

    (Interesting website - even if the connection to involuntary reactions to sounds escapes me. :biggrin:)
  11. Dec 31, 2009 #10
    My cat is deathly afraid of garbage bags being "inflated." Is there any truth to the saying "to bag a cat." Kitty knows so. :surprised
  12. Jan 1, 2010 #11
    i get a similar experience from listening to Bob Dylan sing, even though all the authorities have informed me that he is some kind of genius (a reverse idiot savant syndrome?).

    anticipatory salivation can be evoked in dogs by ringing a bell, if you've already taught them to associate that experience with feeding. so it's probably more than simply a meme.
  13. Jan 2, 2010 #12
    That recalls Pavlov's dog.
  14. Jan 5, 2010 #13
    My daugter gets the same kind of reaction from hearing paper rustling. This is not conditioned, learned or anything but a very powerful visceral rxn to a particular stimulus.

    Now my reaction to George W's voice was learned. It made my skin crawl. Why can't we tickle ourselves? Why are some oblivious to bugs?

    As to why chalk on blackboards is so aversive likely dates to the early days of education and some collectively recalled trauma.

    And while we now have whiteboards and markers, as soon as I start to write equations on the board, the rxn is the same..........
  15. Jan 6, 2010 #14
    That was not Bob Dylan - that was Micky Jagger/Keith Richards.

    "Yeah, when you call my name,
    I salivate lile Pavlov's dog ...."

    (I tried to put in the name - but it becomes ****s .) BAY ITCH might work. :cool:
  16. Jan 6, 2010 #15
    Given the facts that chalkboard fingernail screeching affects nearly everone and your daughter's paper rustling affects almost no one except your daughter, I would argue that it is most certainly a conditional response.


    Bugs? What the...

    It likely dates to gentic memory, given the vastly widespread and often-repeated experiments verifying it's existence.

    I've sat through dozens (actually more than 160) of whiteboard classes and have never once observered or heard of someone experiencing a fingernail/chalkboard reaction to whiteboard markers.
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