So before You go bumping Your gums comparing Phone calls, while driving

With listening to Radio or chatting with other passengers etc etc

Here is the scientific research showing why -

Phone calls (handsfree or not) use Way more of the brain, than other tasks in Car

You want an example - try talking to your partner, while they are on the phone

What normally happens -

You get snapped at - they can ONLY concentrate on that phone call -

and YOU are their partner, the same happens while driving

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