Why Your Brain Lets You Make Grammar Mistakes (Even If You Know Better)

Calling out other people's grammar mistakes has become a favorite internet pastime.

From news articles and blog posts to emails and tweets, if there's an error in there, someone's going to remark on it. Especially if it's made by a brand. (Hey, we're guilty of it, too.)

And who could blame them? I also feel a certain sense of pride when I find a typo in a popular book. Sometimes I circle it with a pencil -- you know, in case the publisher ever puts out a call for typos and I need to find it easily. You never know.

But here's the thing: Grammatical errors don't necessarily mean the author didn't know better. I could go on for days about the differences between "whether" and "weather" -- and yet, for some reason, that one trips me up on a regular basis, especially when I'm texting.

Why? Because our brains are wired in a way that makes us all susceptible to grammar slip-ups.

Let that sink in for a second. No one is safe from making grammar mistakes -- not even the Chief of the Grammar Police.

In fact, some of the most common grammatical errors don't happen because the writer is being careless; they happen because the writer is focused on their writing at a much higher level than the order of letters in a word.

Let's dig in to why.

It's Not Your Fault

Think about how quickly you need to access words and interpret meaning when writing an email or having a conversation. Our brains don't just stow away every individual word in our vocabularies in enormous storehouses, ready to be called upon, one-by-one, at a moment's notice.

Instead, most linguistic researchers agree that words are stored in groups according to the relationship between words. They call the process "word priming."

How does word priming work?

In a study outlined in David A. Sousa's How the Brain Learns to Read, subjects were presented with pairs of words. The first word was called the "prime," and the second word was called the "target." The prime was always a real word, but subjects were told the target could either be a real word or a non-word (like spretz). In the experiment, researchers showed the subjects the prime and the target, and the subjects had to decide as quickly as possible whether the target was a real word.

In every case, people were much faster and more accurate in making decisions about target words that were related in meaning to the prime (like swan/goose) than they were if the prime and target were unrelated (like tulip/goose).

Researchers suspect the reason it took less time for people to identify related pairs is because these words are actually physically closer to one another among the neurons in the brain, and that related words might be stored together in specific cerebral regions.

Another way of framing our tendency to pair words together is that it simply becomes a habit.

Dr. Tom Stafford, a cognitive psychologist at the University of Sheffield who studied Wikipedia edits to see what they reveal about how the brain processes language, told The Washington Post, "When you first start typing, you don't have any habits. And then as you become fluid, that skill is based on the assemblage of routines that you don't have to think about."

Both sets of research are complementary: Scientists have found that when people form habits (like learning to group related words together), the neurons in their brains can change their firing patterns so that these habits become more automated and take less mental energy when they're repeated.

What does this have to do with grammar mistakes?

Andrew Heisel of The Washington Post uses this example:

"If a friend texts that she’s 'going to a concert' and you want to tell her you’re also going, you might type, 'I’m going, to,' instead of 'I’m going, too.' Your brain is used to hearing the word 'going' followed by the word 'to' (as in going to work/school/etc.) and it just saw the phrase used that way in your friend’s text. Conversely, in sentences that should end with the preposition 'to,' people often write 'too' because that word more frequently concludes a sentence."

We all start out our emails and text messages and tweets with a specific concept we want to express, such as the fact that we're also going to the concert. But when we actually type these concepts out, we unconsciously think about several options (like "going to" vs. "going, too") and pick one. This process happens so quickly that we sometimes select the wrong one.

We're especially prone to error when we're choosing between two words or phrases that sound the same.

“Usually we pay a lot of attention to pronunciation while we’re typing because it’s usually a really good cue how to spell things,”says Maryellen MacDonald, a cognitive psychologist at the University of Madison-Wisconsin. “When someone types ‘Are dog is really cute,’ it’s not that they don’t know the difference between ‘are’ and ‘our’; it’s that the pronunciation of ‘our’ in the mind activated the spelling ‘our’ but also ‘are.’”

This can happen with even the oddest of homophones, like when people mistakenly write"28" when they meant to type "20A." An error like that puts the classic your/you're and there/their mistakes into perspective a little bit more.

Grammar Takes a Back Seat to Meaning

In the end, it all comes down to generalization -- what WIRED 's Nick Stockton calls "the hallmark of all higher-level brain functions."

Generalization is the grouping strategy that helps our brains respond quickly to situations similar to one we're already familiar with. It's what helps us take in information, combine it with our habits and past experiences, and then extract meaning from it. And it's fundamental to our ability to communicate.

But, at the same time, it makes us prone to grammatical mistakes no matter how well we can write. Typos aren't usually a result of stupidity or carelessness, Dr. Stafford explains. Instead, they often happen because trying to convey meaning in your writing is actually a very high-level task.

"As with all high-level tasks, your brain generalizes simple, component parts (like turning letters into words and words into sentences) so it can focus on more complex tasks (like combining sentences into complex ideas),"writes Stockton.

Of course, you should still proofread everything and get a fresh pair of eyes to look over your written work. But at least you can rest easier knowing that you made that typo in last week's blog post not because you were ignorant or negligent, but because you were hyper-focused on conveying meaningful information to your readers.

I know I will.