It is known that in US alone around 1000 babies die after being shaken, with an equal number of cases resulting in brain damage. So researchers from University of Oslo decided to investigate injuries caused by shaking and blunt force trauma and created a high-tech doll that would assist them in learning more about brain injuries.

Shaking causes a baby's head to accelerate quickly so the doll's head accelerates in three directions. Under acceleration, the stress on an infant's head can be compared to the worst stress experienced by the pilot of a fighter jet. While shaking can equal ten times the force of gravity (10 G), a fighter pilot can only stand a force of 9 G for a short time before passing out. And in a car accident at 70km (around 43 miles) per hour, the brain is subjected to the force of only a few G.

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