Step inside most modern cars and instead of all the dials and switches
that used to clutter the dashboard you are likely to find it dominated by a touchscreen.
Often there is more than one screen, and some are bigger than those on a laptop.
But, though touchscreens provide a convenient way to operate a multitude of controls and settings,
the latest research shows they can also be dangerous distractions.
To discover how badly touchscreens distract drivers, Neale Kinnear and his colleagues at the Transport Research Laboratory,
a former British-government agency now run as an independent test facility, arranged a series of experiments.
They recruited two groups of 20 drivers. One consisted of regular users of Google's Android Auto,
a popular "infotainment" app which lets drivers interact with their phone through a car's touchscreen.
The others were partisans of Android Auto's main rival, Apple CarPlay.
Each participant completed three 15 minute journeys along a set virtual route using the laboratory's sophisticated driving simulator.
On one of these trips they had to carry out tasks using only the touchscreen.
These tasks included navigating to a restaurant, playing a particular song on Spotify (a music service),
changing radio channels, getting the system to read out a text message, and making a "hands-free" telephone call.
On the second trip they had to do the same, but using only the car's voice-activated controls instead. The third journey was a control, with no assigned tasks.
Whenever a red bar flashed on the windscreen the researchers measured
how long it took a driver to react by pulling the indicator stalk to flash the car's lights.
As they expected, drivers using touch controls on the screen took longer to respond to the flashing bar than did those using voice controls.
Though the difference might be less than a second, at motorway speeds this would result in an increased stopping distance of up to 25 metres.
Dr Kinnear was, however, surprised by the amount of time drivers' attention was diverted by the series of glances needed to operate the screen.
Among the worst outcomes were a mean of 20 seconds of cumulative glances using Android Auto to play a song on Spotify,