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Scratching the Surface: The Itching Quiz
by Staff
With 20 square feet (2 square meters) of surface area covering the average human body, it's no surprise that skin can get itchy. And when hair, dust or other irritants make contact, there's a lot that has to happen before we respond with an almost reflexive scratch. Take our quiz to find out what goes on under the skin when it itches.

About how many square feet of skin does the human body have?

  • 10
  • 20
  • 30

What is the clinical name for itching?

  • itchmitis
  • hyperdermarosis
  • pruritus

When certain stimuli irritate the skin, they send signals to your cerebral cortex through which route?

  • spinal cord
  • arteries
  • cells

How long does it take for your brain to receive the "itch" message?

  • less than a second
  • 10 seconds
  • a minute

What did scientists once think itching was a form of?

  • cold sensations
  • heat sensations
  • pain

The impulse to scratch an itch is meant to achieve what?

  • to numb the source
  • to remove the source
  • to identify the source

Why does scratching temporarily stop itching?

  • Oils on hands and fingernails can reduce itching.
  • It interrupts the "itching" signal to the brain.
  • It removes the cause of the itch.

When you scratch, how many nerve endings do you activate?

  • more than covered by the irritant
  • less than covered by the irritant
  • the same amount as the irritant

What health conditions are known to cause itching?

  • allergies
  • infections
  • both

In addition to skin, what other organ is exposed to constant irritation?

  • the liver
  • the kidneys
  • none