Google "subvocalization," and you'll see pages and pages of productivity resources claiming that our internal speech is the one thing standing between us and lightning-fast reading — and offering tips on how to stop subvocalizing.

Also sometimes called implicit speech, inner speech, silent speech, or inner vocalization, subvocalization is the way we say words inside our heads as we read them — something almost everyone does naturally.

Subvocalization has been studied for over a century, and it's extremely common. But in productivity circles, many people claim that subvocalization is holding you back from reading as quickly and efficiently as you can.

The science behind subvocalization isn't perfectly clear. And while many researchers agree that subvocalization can impact our reading speed, that's far from the full picture. Let's dive into how subvocalization works, why it's slowing you down, and how you can become a faster and better reader — whether you subvocalize or not.

What is subvocalization?

Subvocalization is the process of inaudibly articulating speech with your speech organs. Think of it as the inner voice (likely your own voice) that you might hear while reading words.

Subvocalization involves much more than just thinking words as you read them. It actually involves physical parts of the body, including your eyes, lips, throat, tongue, vocal cords, and larynx! During subvocalization, all the muscles involved in articulating speech sounds move to evoke the sound of a word (silently) as you read it. Subvocalization is characterized by these movements, which are often too small to be detected even by the person who is subvocalizing.

However, the movements are the same as when we speak — NASA scientists have been able to use sensors attached to a subject's throat to transcribe material they are reading silently via the movement of their speech organs.

Subvocalization is a natural process that helps our brains comprehend and remember what we're reading. Muscle memory is the way we learn to perform complex movements involving different muscles and body parts faster and more accurately over time through repeatedly performing those movements. Researchers believe subvocalization uses processes similar to muscle memory, to help store and access the meanings of different words.

Research into subvocal speech has been documented as far back as 1868, when scientists began to consider thinking as "subdued speech". In 1899, a researcher named L Curtis was able to record movement of the larynx during silent reading, and he concluded our "inner voice" while reading causes the same movement in the speech organs as saying the same words out loud. Curtis believed that silent reading is the only mental activity that causes considerable movement in the larynx.

Research continued in 1950, when Ake Edfelt created an electromyography (EMG) device that could record physical movement of all the speech organs during silent reading. Edfelt also experimented with suppressing subvocalization, but he eventually concluded that subvocalization reinforces learning, and disrupting it could interfere with learning and development.

What we know about subvocalization today

Today, subvocalization is considered to be one of the components of Baddeley's model of working memory, a proposal made by English scientists Alan Baddeley and Graham Hitch in 1974. It's their theory that the physical movement that happens during subvocalization is part of the "phonological loop" that helps commit what's being read to your short-term memory.

Scientists are still learning about exactly what's happening in the brain during subvocalization, but they have found that subvocalization causes brain activation (detected via fMRIs) in multiple areas. One of the main areas activated by subvocalization is the Broca's area of the brain, which is the part responsible for speaking.

How common is subvocalization, really?

We don't know exactly how many people subvocalize, but the research shows that it's very common. Subvocalization is most people's default state when reading silently. Deaf people who learned sign language have even been documented to "subvocalize" through tiny, involuntary movements in their fingers and forearms!

This research helps explain why most people's average reading speed — typically 200-250 words per minute (WPM) —  is so similar to their speaking speed, typically 200-240 WPM when speaking quickly. When people subvocalize, they generally can't read faster than they can talk.

Is subvocalization a bad thing?

Definitely not!

Subvocalization is a natural process. Some researchers theorize that humans might not even be able to learn to read if we didn't subvocalize.

Subvocalization is still a concept that's shrouded in mystery. It's generally accepted that, because of the role it's believed to play in reading comprehension and memory, subvocalization is very useful for reading technical materials, learning new words, or memorizing material word-for-word.

Many researchers also agree that subvocalization is one factor that can limit our reading speed.

As Stephen K Reed put it in his book Cognition: Theories and Applications, "Although subvocalising can help us remember what we read, it limits how fast we can read. We could read faster if we didn't translate printed words into speech-based code."

But can you improve your reading speed by eliminating subvocalization altogether? There's even more debate about that.

In Toward a Model of Reading Fluency, S Jay Samuels hypothesized that the most fluent (and fastest) readers actually don't subvocalize.

"[R]eading theorists such as Gough (1972) believe that in high-speed fluent reading, subvocalizing does not actually happen because the speed of silent reading is faster than what would occur if readers said each word silently to themselves as they read," he wrote. "The silent reading speed for 12th graders when reading for meaning is 250 words per minute, whereas the speed for oral reading is only 150 words per minute (Carver, 1990)."

But there's certainly no scientific consensus on whether it's possible to stop subvocalizing — or if that would help or hurt our reading skills.

Those who want to become faster and more efficient readers should know that subvocalization is just one piece of that puzzle. But knowing the important role subvocalization plays in reading comprehension, should you minimize it to increase your reading speed?

Can you become a speed reader despite subvocalization?

The research isn't clear on whether it's even possible to stop subvocalizing. And considering what we do know about the use of subvocalization for comprehension and memory while reading, is it actually beneficial to minimize it?

Can speed reading make us more productive?

A common reason people look for ways to stop subvocalizing is so they can read faster. So let's start there: is there any benefit to being a faster reader?

On the surface, it sure seems like it! On any given workday, most of us spend a lot of time reading: work materials, research, memos, Slack messages, email, and more. Getting through all that reading faster would create more time for other tasks, thus making us more productive, right?

That's the idea behind speed reading courses and tools, some of which have claimed they can help the average person read thousands of WPM. The first popular speed reading course, introduced in 1959 by Evelyn Wood, claimed that people read slowly because they don't read efficiently. The key to speed reading, Wood said, was learning to make fewer back-and-forth movements with your eye, instead taking in more words — several lines of text — with each glance. That idea is also the basis behind apps like SpeedRead With Spritz, designed to train your eyes to take in more words in less time.

Speed reading courses: not backed by science

But as Professor Rebecca Treiman wrote for the New York Times, the problem with speed reading isn't your ability to see the words — it's your ability to process them. That's where the use of subvocalization comes in — it helps you recognize words, process the meaning of what you're reading, and store it all in your memory.

Then there's evidence that we physically can't read much faster than average. Keith Rayner, an eye-movement expert, has published research showing that being able to read more than 500 WPM is highly unlikely, simply because that's the upper limit of what your eye can process. 500 WPM is only about twice as fast as the average reader — far from the thousands of WPM promised by many speed reading resources on the internet.

So what can we do to become better readers, increasing our speed as much as possible without sacrificing comprehension? More on that below...

4 reading and skimming tips for both speed and comprehension

1. Set a goal for your reading

Are you reading to learn about a complex new topic? Or trying to quickly read your day's email so you can move on to other tasks? The type of reading you do will influence the speed at which you can do it — complex material that requires focus and enhanced comprehension should be read more slowly, with a focus on subvocalization which will help you process and remember the material. Email, on the other hand, might be something you can just skim — especially as you use Superhuman to triage your different work streams.

2. Practice skimming techniques

Not everything you read needs to be read deeply — some of it can be skimmed. And while science tells us that speed reading is unlikely to be possible, speed skimming is certainly within reach for many people.

Skimming is scanning text to try to pick up selective words or ideas. In a 2009 study, researchers tested different skimming techniques by asking readers to read essays that:

• Had the first half of the words covered
  
  
• Had the second half of the words covered
  
  
• Had the first half of each paragraph covered
  
  
• Had the second half of each paragraph covered

The researchers found that people performed better on a memory test if they read half-paragraphs, rather than just the first or second half of the essay — and that they performed just as well as people who were asked to skim an entire essay with a short time limit. This reinforces the idea that skimming by reading just the first sentence or 2 of each paragraph can cut down on reading time without sacrificing too much comprehension.

3. Use a pointer

Many speed reading courses recommend using a pointer or your finger to guide your eyes through text at a predetermined rate (say, 1 line per second). This is one part of speed reading that is backed by science, because it's not always easy for our eyes to maintain focus on a piece of text.

Eyes are constantly in motion, and using a pointer can help stabilize natural eye movement and keep your eyes moving smoothly across the text as you read. This may feel unnatural at first, and might actually slow down your reading in the beginning. But over time, practicing steady eye movement will train your eyes to move quickly and smoothly every time you read, rather than jerking or moving backward.

4. Read things you love

Even the fastest readers read slowly if they find the material boring. As you develop your speed reading habit, seek out material you enjoy reading and learning about, and use it to practice these techniques. Over time, it will become easier to apply them — even to reading material you don't love.

Subvocalization isn't stopping you from speed reading

Learning to read faster can increase your productivity by helping you finish reading-based tasks in less time. But when it comes to reading, speed isn't always the most important thing.

As you practice these reading techniques, remember that speed reading isn't the opposite of subvocalization. The key to being the most efficient reader is to balance the two: reading quickly while still gaining the comprehension and memory benefits of subvocalization.