'Tickling is a way to hone down our combat skills'
The world's first 'tickle spa' has opened in Madrid, promising to tickle clients into a state of relaxed bliss.
But why do we laugh when we are being tickled and how can it be a relaxing experience?
Dr Chris Smith from the pathology department at Cambridge University tells Radio 5 live Breakfast why the anticipation of being tickled is a basic survival instinct.
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