'Chemistry Of Fear' VIDEO Explains Science Behind Brain's Response To Dangerous Situations

Do you love haunted houses? Can't get enough of horror movies? During the Halloween season, many thrill-seekers enjoy getting spooked.

But what's really happening in your brain when you scare yourself silly? Check out the video above, the latest episode of the American Chemical Society's ByteSize Science series.

"Fear is the expectation or the anticipation of possible harm," Dr. Abigail Marsh, associate professor of psychology at Georgetown University, says in the video. "We know that the body is highly sensitive to the possibility of threat, so there are multiple pathways that bring that fear information into the brain."

And which part of the brain is central to the fear pathway? The amygdala, an almond-shaped group of nerve cells that release neurotransmitters, chemicals that relay signals in the brain. Neurotransmitters trigger a cascade of responses in the body responsible for that "fight or flight" response -- and that adrenaline rush that not only may be key to our survival in dangerous situations, but also may make scaring yourself so fun. Adrenaline raises your heart rate and blood pressure, and gives you a boost of energy and alertness.

Luckily, the brain dials down the amygdala's response and returns your system to normal if it recognizes that you're not actually in danger -- and you can keep scaring yourself without getting too stressed out.