BALTIMORE - The Mayan calendar ends Friday and some believe this could spell the end of civilization as we know it.
A recent survey found more than 6 million Americans are expecting Thursday to be their last full day on earth.
But a psychologist says this is more about the "fear of the unknown" than it is the world coming to an end.
Scott Bea with the Cleveland Clinic says, "Some people really respond with fear to uncertainty- things they can't predict.
There are media reports of cataclysms: tsunamis, things of that nature that get people guessing at the end of the world.
Now you add the Mayan calendar thing, which may be misinterpreted by many, and this just fuels the fire for people who are anxious about these sorts of things."
He says the majority of people think we'll all be here Saturday morning and beyond, so they're having fun with the notion .
But he concedes that others need more convincing.