Here's a little piece of personal trivia for you -- my husband is a screenwriter. So  around our house there's no shortage of talk about storytelling structure, and the bookcase is full of titles on the topic like Joseph Campbell's classic The Hero with a Thousand Faces.

In short, I've heard a lot about the theory of how to spin a great story. Which is why I found a recent blog post from psychologist and author Susan Weinschenk so illuminating. In it, she delves not just into the how of great storytelling but also the why -- why do these classic structures affect us so profoundly? The answer, apparently, can be found in brain chemistry.

The structure of a great story

For those who don't often discuss characterization and story world over dinner, Weinschenk's post kicks off with a great primer on storytelling theory, explaining the basics of Campbell's thinking (famously exemplified by the journey of Star Wars' Luke Skywalker), as well as the roughly bell-shaped story diagram every writer learns in her first class on structure. You start with exposition of the status quo, rise through dramatic action to some climax, and then gently let the listener/reader/moviegoer down to some kind of denouement.

It's as useful for business owners and marketers looking to captivate customers as it is for novelists and movie pros. But where the post really gets interesting is when Weinschenk explains what happens in the human brain throughout this classic story structure.

This is your brain on storytelling.

Drawing on the work of neuroscientist Paul Zak, who took blood samples from people as they listened to engrossing stories, she explains that you can actually trace the progress of a tale through our brain chemistry.

"Zak found that during the rising action people release cortisol, at the climax people release oxytocin if they feel empathy with the main character, and if there's a happy ending people release dopamine. Interest can be maintained by cycling through these story pieces and keeping the brain chemistry going," writes Weinshenk.

It's a fascinating testament to the primordial power of great storytelling. If you're convinced that humans just can't resist a great story and want to harness a little of this power for your business, there's no shortage of practical advice out there. For example, here's a dead simple guide to crafting compelling stories for those who don't have the natural gift of spinning a yarn.