What does the controller vibration mean in Nintendo Land - Luigi's Ghost Mansion?

For the Nintendo Wii U game "Nintendo Land," there are twelve mini-games based on well-known Nintendo IPs, one of which is based off of Luigi's Mansion: Luigi's Ghost Mansion.

When playing, one player uses the Wii U gamepad, and all the others use Wiimotes. When playing as the player with the Wiimote, the controller starts to vibrate randomly. What does this mean/is there a way to turn it off? It seems like it is doing so to add suspense to the "ghostly" environment of the game, but my friends and I who play the game find it slightly annoying and irritable if it has no real purpose.