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Medical Why aren't hunger thirst and (the need to) sleep considered reflexes?

  1. Jan 19, 2013 #1
    A reflex is an automatic and involuntary response of a living thing to the presence of a stimulus. A reflex is usually a movement, but it can be the activation of secretion in a gland.

    Is it because there is no particular stimulus? Not having eaten, drank, slept for a while is not considered a stimulus?
    Is it because you have to learn what thirst is, you have to learn that drinking solves the problem?

    Thank you.
    Last edited: Jan 19, 2013
  2. jcsd
  3. Jan 19, 2013 #2

    Simon Bridge

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    A reflex is performed without conscious thought - there is no pressing conscious need to do it you just do.
    Properly triggered, a reflex is something you cannot choose not to do ... where you can choose to, say, starve to death.
    There is also a relatively uncomplicated cause and effect involved in a reflex.

    Consider also:
    do you have a "death reflex" that is triggered by the application of large quantities of high-speed lead?
    Last edited: Jan 19, 2013
  4. Jan 20, 2013 #3
    Ok thanks! :)
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