Brain test judges how old you are based on your reaction time

For every 15 years after the age of 24, cognitive speed is said to drop by around 15 per cent

By targeting parts of the brain with a magnet, scientists managed to change subjects' views (MIGUEL MEDINA/AFP/Getty Images)

A multitude of studies have shown how, as we age, our brain reaction time begins to slow down.

In 2014, researchers at Simon Fraser University in Canada analysed 3,305 people aged 16-44 by testing their performance on a real-time strategy video game, and found cognitive decline appears to begin at the age of 24.

For every 15 years after the age of 24, cognitive speed dropped by around 15 per cent.

One test you can try out to see whether this might be the case has just been launched by JustPark, created from a survey of 2,000 people aged 18 and over.

It simulates a drive through a wooded area with warning signs for deer and speed. After a few moments a stop sign will flash up on the screen, at which point you need to click to stop the car.

Click image to open interactive version (via JustPark.com).

Your age is predicted based on the average age of people with your reaction time.

Take the test and let us know how you did in the comments.