Email Subject Lines and the Brain

The inbox is a crowded place. Your message is competing along with hundreds of others that are from people who are likely more important to the recipient than your brand. How can you break through the arena of the inbox and stand out? Use your brain, or more accurately, use your recipient’s brain.

The human brain is an interesting machine, filled with paradoxical mechanisms. It’s so interesting that for almost 150 years many scholars have made it their primary focus. Years of study have revealed that the human brain behaves in certain predictable ways. These cognitive biases (i.e., a brain’s bias, or preference, for one option over another) give us insight into how we as marketers can rise above the noise and truly reach our recipients.

Simply put, the objective of a subject line is twofold:

1. Get attention
2. Cause action (usually an open)

Most marketers focus on the second step of the equation, but both pieces are necessary for a subject line to be successful. The remainder of this column will focus on using cognitive biases and processes to get a recipient’s conscious attention.

Get Attention by Lighting a Fire (Three Methods)

Taking a common-sense approach, we can best understand “attention” as helping the human to notice those things that will aid in survival and potentially increase pleasure or reduce pain. (Many more rigid models of attention have been proposed and studied, but the above simplification will serve for this column.)

If the fundamental unit of processing for the computer is the processor, then the fundamental unit of processing for the brain is the neural network. In the human brain, this neural network is made from 100 billion neurons. Each neuron works by “firing” an electrical impulse when it’s “activated.” The firings of the neurons combine to create human behavior. When we think of getting attention with subject lines, it helps to think about trying to literally cause the firing of neurons in the brain.

Note: Each of the methods below will help you get attention, but can be abused and become worthless if they aren’t paired with a respect of the consumer’s desires. These methods function to bring your subject line from the subconscious into conscious awareness. Once it gets there, it’s still your job to make the subject line relevant and attractive (see the section on causing action).

Method 1: Use Certain Emotional or Personal Words to Grab Attention (the Cocktail Party Effect)

Have you ever been at a party, having a discussion, when someone across the room brings up your name? You suddenly shift your attention to that source, evaluating whether or not more attention is required. Is someone asking for your attention, talking about you, or merely discussing someone else with the same name?

This is called (appropriately) the Cocktail Party Effect. Before your name was spoken, the conversation was just background noise to you. Once your name was said, you immediately shifted your attention. You were already hearing the other conversations in the room at a subconscious level, but once your name was said, your brain brought the conversation to the level of attention to be processed and dealt with by a more powerful part of your brain.

Just like someone at a cocktail party, your subscribers’ brains treat an inbox as a collection of noise, much of which is so unremarkable that it doesn’t warrant conscious attention. To rise above the subconscious, you can leverage the Cocktail Party Effect.

Use a Name

The recipient almost can’t help but pay attention when her name is used; it’s hardwired in her brain after decades of programming. Putting a consumer’s name in a subject line is almost guaranteed to get her attention.

Two caveats to this method: first, if you use it too much, the salience (see the next tip below) will be lowered so much that the recipient will learn to ignore you, or just unsubscribe to avoid further annoyance. (Imagine someone calling your name and then giving you nothing important…eventually you’d just ignore them.)

Second caveat: you’ll need more than a name to get action. A name will get attention almost every time, but it’s the rest of the subject line, and the use of the name in the subject line (e.g., there should be a reason for there to be a name) that will cause an action to occur.

Use Another Trigger Word

Though less effective than a name, words like “free,” “limited,” “urgent,” “attention,” “need,” etc. also cause subject lines to rise out of the fog of the subconscious to be attended consciously. If you’re wondering what words count as trigger words (i.e., those that trigger conscious attention), simply think about what words cause you to suddenly shift your attention to something.

Just like with a name, you need to have a good reason to use these words, and you need to use them sparingly. Overuse will cause subscribers to leave and complain, even more so than overuse of a name.

Method 2: Increase the “Standoutness” of Your Subject (Salience)

Salience is the quality of how much one thing stands out in a group. Someone with red hair surrounded by people with brown hair can be said to have high salience.

Your emails sit in an inbox of tens or hundreds of other email subject lines. Humans can only effectively evaluate one thing at a time, but they group things together that appear similar to process them more efficiently. (Have you ever had a group of three coins that you thought were all quarters, but on closer inspection found one to be a foreign coin, or a dollar coin?)

If your subject line is similar in length, structure, and visual appearance as others, it’s very likely to be grouped with those others and ignored.

To stand out, you need to be different. Try icons in your subject lines. Use only two words. Use all lowercase or all caps. Most marketers grasp this intuitively after years of experience, so you should be happy to learn there is some science to back up your intuition.

Method 3: Don’t Habituate Your Subscribers (Operant Conditioning)

Think of a brand that sends you email. Now imagine that each one of their emails had the subject line “Stuff from Brand X.” Right after signing up, you would open, since the original interest is still there, but this original interest will quickly fade. Unless you form a strong emotional connection to Brand X, you’re unlikely to pay attention to “Stuff from Brand X” when you see it in your inbox unless you’ve got nothing better to do (equally unlikely).

Just like you’ve learned to ignore the particular smudges on that stop sign right next to your house, or the number of stairs you climb to get to your office, you’ve learned to ignore this subject line, since it’s predictable and unchanging. Your brain is helping you by programming itself to ignore things that don’t provide relevant information to your life.

This is an extreme example, but I see it (because I purposely look for it) in my inbox daily: brands that always start a subject line with “XX% off…” or “Breaking News…” These subject lines quickly get marked to be archived for later processing (which almost never happens) or deleted. My subconscious brain decided that there is nothing new there for me, and I’ve got other things to pay attention to.

To fight this, change it up. Drastically shift the number of words in your subject line. Use all caps if you haven’t, and stop using it if you do all the time. You can even make a subtle change to your from name. These small changes will cause your recipient’s subconscious to say, “Hey, something has changed; I better pay attention.”

Note: Each of the three methods above requires tact and restraint to use effectively. A common theme is that overuse of any of these methods destroys their effectiveness.

Before you can get an open, your subscriber must pay conscious attention to your subjects. In order to do that, you must play to the programed tendencies of that subscriber’s brain.

Brain image on home page via Shutterstock.

Editor’s Note: As 2013 comes to a close, we’re pleased to share our top email columns of the year. This article was originally published January 8, 2013.