Structuring your novel’s big picture is important. The structure of your scenes all the way down to your character’s motivations and reactions are equally important. If you get the sequence out of order, you risk confusing or completely disengaging your reader. Don’t worry. You can create compelling scenes with the MRU. The motivation-reaction unit (MRU) is a tool introduced by Dwight V. Swain in his book, Techniques of the Selling Writer. This post is only an introduction to the MRU. In his book, Mr. Swain does a deep dive into the MRU and other tools writers can use to be a selling writer.
“A story is a series of motivation-reaction units. The chain they form as they link together is the pattern of emotion.”
Techniques of the Selling Writer, Dwight V. Swain.
What is the MRU?
In Techniques of the Selling Writer, Mr. Swain uses his understanding of the pattern of emotion (how people’s brains work) to create a guideline for writing fiction. He calls it the motivation-reaction unit (MRU) and breaks it down into parts.
At its simplest, the MRU is—
In the book, Mr. Swain talks about each part of the MRU in great detail. Read it to get a deeper understanding of the MRU. He also discusses what story is, story structure, character, conflict, and ways to be a successful professional writer.
How Your Brain Reacts to Stimuli
People react to a stimulus predictably. There are simple responses, more detailed responses and complex responses. What we think varies. What we feel varies. What we do and say varies. But each of our brains reacts to a stimulus in the same pattern.
A stimulus is something that directly rouses a reaction or activity. We pick up stimuli with one of our senses: sight, touch, hearing, smell, taste. Neurons in your brain process the stimulus and cause a sequence of responses. The blink of an eye is one reflex that happens instantly. Some responses we learned at an early age— don’t touch the hot stove. We gain some after repeated experiences, and some responses need to be processed on a higher level of thought that might take hours to months.
Simplest Stimulus and Response
A reflex is your body’s simplest response. A dangerous stimulus causes an immediate motor response.
Stimulus: Something flies toward your eye.
Response: You blink without a conscious thought.
More Complicated Stimulus and Response
The more complicated the stimuli, the more complicated your response. Your brain processes this in nanoseconds and your body responds in seconds or minutes.
Stimulus: You feel the pain of a bee stinging you.
Reaction: You want to stop the pain, slap at the bee, and yell.
Complex Stimuli and Response
Some stimuli, particularly social ones, are far more complex and trigger a complex response.
Stimulus: Your ex-husband confronts you at a public event and loudly demands that you admit your much loved, recently departed, second husband abused you.
Reaction: Confused and hurt, you play the words in your head again,. You knot your hands into fists. You politely deny the accusation and you excuse yourself from the uncomfortable situation. Later, you replay the scene in your head; you remember similar conversations with your ex, and your suppressed anger boils. You curse loudly and deface your ex’s expensive car.
How to Create an Effective Motivation
Motivation always comes before reaction. But what motivation is Mr. Swain talking about? He’s not talking about the motivation to pick up a coffee mug or sniff a flower on your morning walk. He refines the term motivation to motivating stimulus. A motivating stimulus is “anything outside your focal character to which he reacts.” The important word in that definition is “outside.” It’s not a thought or worry. Those may be part of a scene’s sequel, but the motivating stimulus comes from outside—another character’s presence or actions, the weather, or the situation.
To be an effective motivating stimulus, it must be something that is significant to your focal character. It must be significant enough that it demands your focal character react actively. Because of her personality or needs, or wants, she must act.
The best motivating stimulus is also pertinent to your story. The writer selects a stimulus that sets up the change you want your focal character to experience. It is a change in your focal character’s external world. This change stimulates the focal character to change his internal thoughts or ways of doing things.
The stimulus also must make sense to your reader. You will jerk your reader out of the story if your focal character has hated guns from the beginning and in chapter twenty, she picks up a gun and shoots accurately.
If your motivating stimulus doesn’t do all these things, your story or scene will be less effective and possibly be the place your reader puts it down, never to pick it up again.
The R (Reaction) in MRU
Your character’s reaction is anything your character feels, says, or thinks because of the motivating stimulus.
Mr. Swain breaks the Reaction portion of the MRU down into three parts: feeling, action, and speech. This is the order in which they should appear on the page in order for your reader to process the story. Below is the M-R from the reaping scene in The Hunger Games.
Effie Trinket announces Katniss’s little sister, Prim, is the next participant in a deadly competition.
Shocked, Katniss stands rooted to the spot and watches her sister move forward. She follows her sister. She shouts Prim’s name over and over. Then, realizing Prim will never survive the “game,” Katniss volunteers to take her sister’s place.
How to Create an Effective Reaction
Like the Motivating Stimulus, the Reaction must be significant, pertinent, and motive. It also must be characteristic and reasonable.
The reaction is significant when it creates the character change and moves the story forward in a way that you, the writer, intended. We see that in the reaping scene from The Hunger Games.
Mr Swain uses the term motive to describe a character doing something. The character’s reaction is motive if it is active, particularly if it leads to more change. The reader expects that Katniss’s reaction of volunteering as tribute will change her life.
A characteristic reaction is typical behavior of your focal character. It can be unexpected or stronger than usual, but it is in keeping with the character’s personality. It should be a reasonable response to the stimulus. In The Hunger Games, the reader knows Katniss is protective of her sister and accepts Katniss volunteering as characteristic.
Why use MRUs in your Writing?
Consider a motivation-reaction unit where your mild-mannered character, a middle-aged woman, receives a blackmail note. Your character’s reaction is to confront her daughter and to demand if the photo is of her. Then your character shakes and cries and wrings her hands and you learn she’d received the blackmail note with a lewd picture of her daughter. She doesn’t have that much money. Maybe the photo isn’t of her daughter. But it won’t matter if once it’s on the internet everyone thinks it’s her daughter.
Confused? Yeah. When the writer reveals motivation and reaction randomly, it’s hard to follow.
Rewind that scene, this time we’ll us