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Why does scratching an itch feel so good for so little time?

Scratching can feel satisfying even when the itch returns soon afterward. Relief, pleasure, and removal of the original cause are separate things. Researchers can measure the first two during a controlled itch task without assuming that the underlying irritation has disappeared.

3–7 min

Questions you could explore

  • How could an experiment tell pleasurable scratching apart from itch relief?
  • Why might a brief change in sensation leave the itch-scratch cycle going?

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How does daylight set the body’s clock?

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3–5 min

How does daylight set the body’s clock?

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4–5 min

How does a vaccine give the immune system a memory?

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Health and the body

Why won’t an antibiotic treat a viral cold?

The word infection covers illnesses caused by very different organisms. An antibiotic that helps against certain bacteria has no matching target in the viruses that cause a cold.

2–3 min

Why won’t an antibiotic treat a viral cold?

Health and the body2–3 minThe word infection covers illnesses caused by very different organisms. An antibiotic that helps against certain bacteria has no matching target in the viruses that cause a cold.

Why does scratching an itch feel so good for so little time? | Speech Topic | speaking.app