When Professor Jaak Panksepp started his career, his ideas were considered avant-garde. However, he established a global reputation as one of the world's leading neurobiologists and all because he discovered he could hear rats squeak.

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Taken from 'Horizon: The Science of Laughter' (2016)
What exactly is laughter? We all do it, from almost the second we're born - but why? Referred to by experts as the enemy of breathing, Horizon learns how modern science is revealing just how complex this obscure behaviour is and how pivotal it's been to our evolution as a species. Join Horizon on this witty and absorbing trip across the globe, into the surprisingly understudied world of laughter science.

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