The Standard Habit Model:

Roughly speaking, the standard definition of a habit is that of “an automatic behavior that is cued by context from the situation” *4 †1.

Basically, habits can be thought of as your default responses to different situations.

This model for habits is composed of two parts: the context cue and the response.

Pentagrams not included.

The context cue, also called the “trigger” or “situation”, is what first kicks off the entire process. Context cues are typically external things in the environment, from people to sensory details to preceding actions.

Once the cue occurs, the response is generated.

The response, also called the “action”, is the behavior that follows the cue. Responses are typically small, atomic actions, but there is some research suggesting that a series of actions can be “chunked” together into a unit that follows from the response *5.

(However, we also know that actions which require more thought and conscious effort don’t become habitual, even when repeated in the same context *6. Thus, I’ll be recommending simpler responses when we get to creating our own habits.)

This [Context cue] → [Response] model is the core of how habits work.

While this model might seem obvious or simplistic, I’d like to stress the usefulness of this definition. This model allows for much of what we intuitively label as “habits” to fit this template of [Context cue] → [Response].

Here are some examples of how typical habits fit under this model:

Ring! Your alarm shakes you awake. In response, your arm slaps the alarm, hitting the Snooze button, and you go back to sleep.

[Context cue] Shrill sound of alarm going off.

[Response] Turn it off and go back to sleep. Hey! Someone asks you “How are you doing?” and you instantly respond with “Good, you?”

[Context cue] The words “How are are you doing?”

[Response] Immediately saying “Good, you?” Beep beep! You open the car door and get inside. After stepping into the car, your hands are already looking for the seatbelt.

[Context cue] Opening the car door.

[Response] Putting on the seatbelt.

Moreover, I think this model is important in that it stresses how much of our behavior isn’t directly under our control. It highlights how habits can be seen as a way of outsourcing our behavior to the environment.

There’s a very real sense in which the central point of control shifts from internal to external.

But how exactly do habits form in the first place?

In simplified terms, the mechanism behind how habits form looks like this:

Perform an action that isn’t too complex.

EX: You floss your teeth. Keep performing the action in a stable context.

EX: You always floss your teeth after brushing. Your brain begins to make associations between the context when the action is performed and the action itself.

EX: <Insert your brain activity here.> Continue performing the behavior frequently in the context.

EX: Richard keeps up his flossing habit after he brushes his teeth. Over time, the entire habit loop becomes internalized and largely automatic.

EX: Richard ends up with a flossing habit.

5 steps. But not a pentagram.

Much of the actual complexity is in Step 3, where our brains are able to somehow store the information about both the context cue and response together. There’s a question here of “How are habits actually stored in the brain?”

There are two suggested mechanisms for how this actually happens: motivated cuing and direct cuing *7.

The first mechanism, motivated cuing, suggests that certain cues can cause us to act because we anticipate a reward as a result of our actions.

Thus, the cue itself brings to mind a sense of “desiredness” which leads us to act.

A good example is notifications on Facebook. Many people feel a nagging draw to click on the red notification button as soon as they see it, like a sort of mental itch they need to scratch. There’s a two-step phenomenon here, something like [See Facebook notification] -> [Click on it].

Motivated cuing says that this is because past experience with the cue (i.e. the red notification icon) has led to rewards (i.e. information about online activity that involves you).

This means that one way habits could come about is by triggering a motivation to act when we experience just the situation itself (even if the accompanying reward hasn’t shown up yet).

So it sounds plausible enough. But how do know something like this is actually happening in the brain? One good piece of evidence is a classic study involving monkeys and juice.

Here’s what happened: We started with some monkeys, some juice, and a light. We trained the monkeys to push a lever when they saw the light flash, which would then reward them with the juice. When the monkeys received juice, we saw a spike of brain activity (as we might have expected).

Eventually, though, we saw the monkeys’ brain activity shift. Rather than spiking when they received the juice, we began to see the spike when they merely saw the light. In other words, the monkeys seemed to react to the context cue that signaled the reward rather than the reward itself *8.

Basically, this means that one way habits could come about is by triggering a motivation to act when we experience certain context cues.

However, I think the motivated cuing model is unsatisfactory for several reasons. Many of our routines don’t always have well-defined rewards, like folding laundry or drying off with a towel. Additionally, as we’ll see in the next section, rewards seem to have an overall negative effect on habit formation.

This is where the second model, direct cuing, comes in. Direct cuing suggests that when we perform the same actions often enough, one after another, a link will form between them.

For example, consistently putting on the seatbelt after getting into the car can lead to an association forming as we chunk the two actions in our brains, one after another. Thus, once we get into the car, our next automatic step is to look for the seatbelt.

Other simple actions are things like tying our shoelaces right after we put on our shoes or using the same conversation starters (EX: “Have you seen anything good lately?”) with the same friend again and again.

In direct cuing, the most important consideration is repetition.

But didn’t I say earlier that frequency wasn’t enough? And how does the brain know which actions are the ones to chain together to form habits anyway?

Um. To answer the first one, I hope I’ve made clear that, while frequency or repetition isn’t the whole story, it’s an important piece. There are other important factors like a stable context and other things we’ll cover soon.

As for the second one, I’m actually not quite sure. All I know is that in procedural memory (the part of memory responsible for our actions) something called Hebbian learning happens. And Hebbian learning is a mechanism for neurons to link together after they fire in sequence *9.

So this is a rough idea of how linked actions or thoughts could form habits in the brain using the direct cuing model. It’s definitely on shakier ground than motivated cuing.

However, I think that direct cuing still seems a little more plausible because it’s able to (sort of) model a greater range of habit formation, while motivated cuing is stuck to a stricter type of habit.

Ultimately, I just want to stress that I am not an expert in neuroscience. Please take both explanations as my humble attempt at a plain English translation. In addition to simplifications I made to aid in explanation, I’m sure I also made a few straight-up errors along the way.