Believe it or not, this actually has been tested out, and by no less an institution than the United States Military. Learn about a fear experiment that should have led to a lot of "discharged with sincere apologies," notes on service records.
Hey, ever wondered what mortal terror would do to your ability to remember and record the minutiae of your life? If I had to take a guess, I would say that terrible, terrible fear would cause me difficulty in remembering my zip code. (I already have to double-check my driver's license after close ebay auctions. Those can shake a person up!)
Ah, argued the United States military, but how can we be sure? Then they came up with a way to be sure. It's tough to say who exactly made the final decision on any phase of this experiment, but we now know that, one day in the swinging sixties a plane took off from Fort Hunter Liggett in California. It climbed to 5000 feet, it leveled off, and then, after a few calm minutes, it shook its passengers around like an etch-a-sketch. Exactly like an etch-a-sketch, in fact, because the clear implication was that everyone on board was going to be erased. The flight crew soon confirmed this, and told the soldiers that, in order for any member of their family to get benefits from their death, they had to fill out a few forms. Amazingly, the soldiers did their very best.
Their best, as it turned out, didn't compare to the forms they had filled out before, when they were calm and on the ground, and didn't expect to die. The military took this valuable information and probably did something with it. Maybe. We don't know.
What we do know is that the soldiers were what is known in the involuntary human experimentation trade as "understandably peeved." Once their brains were no longer impaired by fear, they got resourceful. Guessing, (correctly, as it turned out) that this was the designated fear experiment plane, they wrote messages on the air sickness bags to upcoming subjects, telling them not to be afraid when the plane started shaking and they were told it would crash because it was all a simulation.
Image: Timothy L Hale