Narrator: Who has a PhD in horror. McKendry: So, jump scares are based on kind of a theory of what fear is. Fear is kind of the buildup. It's the time in between when you think something might ...

There are different types of jump scares, and you’ve probably seen them all. They can either add to the thrill ride or just come across as a series of annoying bangs. Some may think they’re cheats but ...