Measuring skull pressure without the headache Space research has
developed a new way of measuring the pressure inside your skull
using simple sound waves from headphones. The device is an
effective early-warning system for patients recovering from head
injury or brain surgery. Just like blood pressure, our bodies
control the fluid pressure around the brain to cushion it from
hitting the skull. Astronauts rely on their body’s pressure
control system to regulate fluid build-up in orbit, so space
agencies are keen to understand how it works and adapts to
weightlessness. Monitoring ‘intracranial pressure’ is not
straightforward – there are many techniques but they are
cumbersome, invasive and require professional operation. In
1994, Paul Avan from the University of Auvergne in Clermont-
Ferrand, France, investigated the possibility of measuring
changes in pressure by looking instead at a connected area:
inner-ear pressure. He developed a device that beams sound into
the ear and listens to the echoes to calculate t