There is now a phenomenon called 'Phantom Vibration Syndrome'. It occurs when someone regularly has their phone set to vibrate. They feel phantom vibrations on their leg - even when their phone is not present. Up to 90% of US University students experience these phantom vibrations.
Why should you consider switching to a dumbphone. You will have more time, be more efficient and more productive. I would recommend it because you will be less stressed, happier and more attentive to those around you.