How much do you know about nightmares?

What symptoms can you experience physiologically during a nightmare?

A. Sweating

B. Heavy breathing

C. Release of adrenaline

D. All of the above

D. All of the above. Nightmares can cause a number of physical responses that the sleeper would feel facing a real threat.

What fraction of the general population reports experiencing nightmares every week?

A. Half

B. A fifth

C. A quarter

D. A tenth.

B. About a fifth of the general population reports experiencing nightmares weekly.

True or False: Nightmares can be good for you.

A. True

B. False

C. It’s complicated

A. True. Unless they’re post-traumatic-stress dreams forcing you to relive trauma, garden variety nightmares can help you pinpoint anxiety triggers or deal with real-life scary situations.

True or False: you can train your brain away from nightmares.

A. True

B. False

C. It’s complicated

C. It’s complicated. There are certain techniques that might help control your dreams, like thinking about positive imagery as you wait to fall asleep, but the occasional nightmare might still slip through.

Speaking of nightmares, what’s the psychological reason behind the fear of clowns?

A. Their eerie laughter

B. The fact that so many of them can fit in one tiny car

C. How they look human, but not human enough

D. Their huge feet

C. How they look human, but not human enough. This is referred to as the Uncanny Valley, where a humanoid figure looks just off enough to be creepy.