Listening and driving could be as dangerous as drinking and driving, according to a new study.
Research shows that listening to a car radio or a chatting passenger can impair driving in a similar way to drinking.
An American team, led by British-born Professor Marcel Just, has concluded that even simple tasks, such as listening to someone speaking while driving, result in 'reliably degraded driving performance'.
The research was done by connecting 29 participants to an MRI (Magnetic Resonance Imaging) brain scanner while they were steering a car along a winding road in a simulator.
The participants steered while listening to general knowledge sentences, which they verified as true or false using response buttons in their other hand.
Reaction time and accuracy were monitored and performance on the simulated driving task was assessed.
The study showed that adding a listening task decreased the brain function associated with driving by 37%.
Previous studies had suggested that driving and listening used two different parts of the brain and could work independently of each other, thus allowing the driver to multi-task safely.