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The effects of electrical shock on the brain from non-localized contact area

  1. Sep 3, 2010 #1
    In my attempt to obliterate my ignorance I'd like to discuss something related to the recent news story about a young man who attached two clamps to his nipples and then had a friend plug it into a wall socket. http://news.gather.com/viewArticle.action?articleId=281474978486647" [Broken] <-- News Story

    I got into a debate(from an admittedly relative point of ignorance) over whether or not the young man suffered direct brain damage from the shock or if it was entirely the oxygen deprivation from his heart stopping.

    Basically, "their" argument was that it probably didn't hit his brain because it took the path of least resistance. My argument was that given the amount of fluid in the body and the nature of the central nervous system and its connection to the brain it would seem dubious that the brain would not incur direct electrical damage. Now, a second question: if the young man's brain was indeed directly damaged (rather than indirectly via oxygen deprivation), was the voltage enough to cause a significant amount of brain damage? And, I'm not even sure what constitutes "significant" brain damage.

    Also, I was reading up on "path of least resistance" when I came upon this article: http://ecmweb.com/mag/electric_path_least_resistance/. So, unless I'm misunderstanding, the electrical current took every path available in his body in inverse proportion to the amount of resistance in each path? I guess what it comes down to is the bio-conductivity of the connections of the chest to the brain.

    Well, I'd like to assert that while I'd enjoy being correct, my real goal is to understand. Thank you for your time!
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Sep 3, 2010 #2
    Pretty much, so since the current has to go well out of it's way to get his brain it's only a slight percent. Otherwise tazers would constantly shut your heart down and fry your brains etc.

    He would definately have died of a heart attack.

    EDIT: NM he didn't die, but you know what I mean. He suffered brain damage because his heart shut down. His heart shut down because the electricity took the direct path (through his heart/chest). Only a SUPER TINY amount of volage if any would be applied a the brain area.
     
    Last edited: Sep 3, 2010
  4. Sep 3, 2010 #3
    Current flow generally spreads to fill all available paths, which is why the electrical resistance for a conductive flat surface is measured in ohms/square. The size of the square doesn't matter because as the distance the current must cross increases, the width of the area it can pass through also increases. A square inch and a square mile would have the same resistance.

    However, because the head is separated from the thorax by the neck, the currently flow would probably be (mostly) choked off (no pun intended) without much current passing through the brain.

    BillDoor: Are you a fan of Terry Pratchett? One of his characters used the name "Bill Door".
     
  5. Sep 4, 2010 #4
    Thank you for both of your replies!

    And yes, I am indeed a stalwart fan of Pratchett. DEATH's guise as Bill Door is one of my favorite parts of his books, but especially "The Reaper Man."
     
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