Vibration and its effect on sleep

Have you ever fell asleep on the bus or subway ride home? If so, you'd know that vibration can put you to sleep very quickly. I've always wondered why and how it succeeded at doing so. I've already considered a few relations to baby cribs and that's why parents will rock it to make their infant fall asleep quicker. What is it about the notion of continued movement at a constant speed and how does it put you to sleep?

Anyone care to take a guess?

I never thought it was the vibration. I thought it was just boredom.

Cybr said:

I never thought it was the vibration. I thought it was just boredom.

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I also thought that too.

Cybr said:

I never thought it was the vibration. I thought it was just boredom.

Click to expand...

To each his own.

I can't fall asleep on a bus or train. Unless it's a legit train, that barely shakes. But I'm used to NYC Subway, so yeah... it shakes a lot.