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Watch this one together

~6 min · materials: none

How can one little bump make two different pain feelings?

A small bump can leave you noticing a prickly sting and a warm, spreading ache. One knee launched both feelings—but their timing is a mystery until you race the two message fibers.

Talk about it

  • What did the one-fiber node slider teach, and what did it deliberately not compare?
  • At the hinge, name every visible difference between fiber A and fiber B before guessing.
  • Why is a child-driven timeline stronger evidence than a sentence telling you the result?
Watch it together

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