Why slow-motion footage has emotional impact

The slow-mo effect: it gets me every time. The footballer leaps for the ball, the lovers lean in for a kiss, the lost dog runs to its owner, time slows down and I feel a prickling behind my eyes. It's the oldest cinematic trick in the book but I can't stop myself tearing up. Why does slow-motion footage have such an emotional impact?

The internets are full of this stuff. You could spend all day watching things happen at snail's pace: bubbles rising, watermelons exploding, hurdlers hurdling, birds flapping their wings. With slow-mo you see all the minute details that you miss in real time. It's immersive and it's hypnotic.

In sport the slow-mo replay shows us how the impossible becomes possible. We see individual muscle tendons contracting as the rugby player floats over the line. We understand the physical risks involved in this split-second of play. Power becomes superpower when time slows down.

Slow-mo scenes in TV drama reveal the astonishing complexity of human feelings. In an episode of the ABC crime series Mystery Road a body is discovered and loved ones must be told. Dialogue becomes redundant as the actor's facial expression moves from fear to disbelief to horror and finally to abject grief. Compared to the shorthand of an emoji, it's a cornucopia of emotions.