Endless Phonics: The Reading Brain

How the Brain Learns to Read

The human brain is not pre-wired for reading. Reading is a fairly new invention in the timeline of humanity, and our brains must be trained in order to learn to read.

We didn’t always realize that this was the case. This is why many schools have historically taught reading in problematic ways. But with the advent of neuroimaging, we now know exactly what happens in the brain when learning to read. We know the neural connections that aren’t there in pre-readers, but which start to grow and strengthen when reading is taught explicitly. We know exactly what the brain of a good reader looks like, and intervention studies show us how to get there. Stay tuned for my post on Reading Interventions. Got a bit of time? Watch these excellent videos about the Reading Brain and How the Brain Rewires Itself For Reading (this last one includes some kid-friendly language to talk about these concepts).

The Key Components of the Reading Brain

Reading is an activity that utilizes many processing centers in the brain’s Left Hemisphere. In order to learn to read, connections must be developed between these processing centers, building a strong set of information highways or a "reading circuit" in the brain.

Sound & Phonological Centers - located in the Frontal and Parietal Lobes

Meaning Processing Center - located in the Frontal and Temporal Lobes

Visual Processing Center - the Visual Cortex in the Occipital Lobe

Prior to reading, our brain has connections between its sound and meaning processors; we can speak or hear a word and know what it means. But our brain has not connected visible letters to speech sounds or meaning. These are the connections that our brain must build when we learn to read. In skilled readers, most of the work of reading happens in the left hemisphere. In weaker readers, sometimes sections of the right hemisphere will try to compensate, but most dyslexic readers are able to develop normalized neural reading networks with proper intervention. Learn more about the Reading Brain, and Dyslexia and the Brain.

The Reading Process in the Brain: A Quick Overview

Reading begins in the back of the brain, when the visual processor interprets the written letters on the page and processes them as recognizable symbols. From here, there are two reading routes: a word is either read sound-by-sound by the phonological processor, OR the string of letters is instantly recognized by the Visual Word Form Area (colloquially known as the brain's "Letterbox") as a word that has been seen before and stored in long term memory. Finally, using the structure and context of the passage, the child will ensure that they are assigning the right meaning to the word. This last check is necessary if the word is a “homograph” with multiple meanings. For example “BOW” could refer to a formal gesture at the end of a performance, the prow of a ship, a shiny decoration on a gift, a weapon, a tool for playing the violin, or a clothing accessory.

There are many connections that need to be developed in the brain before a child will become a fluent reader. Let’s look at these now:

Building Neural Circuits

In order to learn to read, our brain must build connections between the visible letters we see and the sounds which those letters and combinations of letters can represent. This might sound deceptively simple, but it actually requires us to stretch, exercise, and re-build our Phonological (Sound) Processing Systems and Visual Processing Systems to do things that they haven’t done before.

Sound Processing

Our brain’s Phonological Processor must learn to segment speech sounds in ways that it is not used to doing, unless we’ve done a lot of word chaining and sound-swapping word play.

There are approximately 44 sounds in the English language, though this will vary a bit by regional dialect. Fore example: Australia: Sounds & Letters. Want to hear the sounds? Check out these videos: US / AUS / UK . However, when we speak, we say words as one continuous stream of speech. Breaking the words into individual, distinct sounds so that we can assign a visible letter to each sound can be very challenging for some kiddos, and it may take many repetitions.. For example, the word "bat" can be broken into distinct, individual sounds / b / a / t / and if the / b / is replaced with / m / the word will change to "mat." Segmenting, blending, and manipulating sounds in words is a skill is called Phonemic Awareness, and it is not intuitive for many children. It will require training and practice. Phonics and phonemic awareness instruction play a crucial role in developing these areas of the brain. However, many complications can impact phonological processing, and may require further intervention. Distinguishing speech sounds may be difficult if a student has: hearing issues, auditory processing disorders, articulation problems, or other problems distinguishing between similar speech sounds, such as voiced and unvoiced pairs (vocal cords on, vocal cords off: g / c … b / p … d / t … etc. ), or similar vowel sounds ( such as short i and short e ). The International Dyslexia Association defines Dyslexia as “typically resulting in a deficit in the phonological component of language,” so deficits in phonological (sound) processing are often considered “dyslexia." Note, however, that issues in the phonological processor are not the only issues that impact a child's ability to read well.

Read more about Phonological Processing Issues, Auditory Processing Issues, Articulation Issues, and stay tuned for my post on Phonics, Phonemic Awareness, and Decoding.

Visual Processing

In addition to developing our brain's Phonological (Sound) Processor, our Visual Processor, meanwhile, must learn to process the individual letters of a word rapidly and precisely. This is easier said than done for a number of reasons.

First, our brains are wired to operate in a 3D world. We can rapidly distinguish a dog from a cat, and a chair from any angle. Why is this a problem? Letters and numbers are 2D shapes with very little distinction between them. Reading requires us to develop neural processing that is much more fine-grained and attuned for rapid scrutiny of things that, superficially, look incredibly similar. It also requires us to train our brain not to mentally flip letters, numbers, and words left to right or up and down. This is no small feat, as our brain is automatically designed to mentally rotate every other object in the world, a process called mirror invariance. Ever wonder why kids confuse b and d, or p and q, or sometimes write entire words or sentences backwards? This is why! Our brains are designed to rotate any and all objects. A chair is a chair is a chair, whether we look at it fron the front, side, back, or upside-down. Over time, with lots of practice reading and writing letters, we eventually train our brains to selectively turn this auto-rotate feature OFF for letters and numbers. But it can be hard.

Many other complications can arise when a reader’s eyes and brain attempt to take in visual information. These include vision issues such as Convergence Insufficiency (which is not picked up in a standard eye-exam, by the way, and can occur in kids with 20/20 vision), or visuo-attentional processing issues. In these cases, the brain has trouble processing the letters swiftly, keeping the letters in order, and tuning out “noise” (surrounding letters). ADHD can cause further complications. While many organizations don’t label issues with vision or the visual processing system as “dyslexia” per se, these issues certainly impact reading for many children. Stay tuned for my post on Visual Processing Issues.

Letter-Sound Integration

As if our brains didn’t have enough to work on with sounds in isolation and keeping letters in order, it also has to learn how to bring sounds and letters together. In order to read fluently, our brain must instantly recognize that a particular letter or group of letters can represent a particular sound. The brain must build connections between the Visual Processing Center and the Sound Processing Center.

Unfortunately, English has what is called a complex or “deep” orthography. Basically, this means that: (1) Letters can represent more than one sound. For example, the Letter A can represent many sounds, as in: April, as, wash, was, luggage, many etc. (2) Sounds can be represented by more than one letter. For example, the “Long A” sound as in “cake” can be spelled several ways: <ai> <ay> <a> <a_e> <eigh> <ea>. So while English has 26 letters, these they are used to represent about 44 sounds, for a total of well over 200 common letter-sound patterns (also called grapheme-phoneme-correspondences). That’s a lot.

English’s “deep orthography” stands in contrast to simpler “shallow orthographies” where one letter often represents one sound (see, for example, Finnish). For most children learning to read English, training their brain to learn these complex letter-sound relationships (known as “phonics”) requires a carefully constructed Structured Literacy program with a Phonics scope & sequence, explicit instruction, and lots of practice. Stay tuned for my post on Phonics, Phonemic Awareness, and Decoding.

Mini Glossary Moment:

Phoneme = an individual speech sound

Grapheme = the spelling of a phoneme (can be one letter, or multiple letters - ie. a digraph (like the <ea> in bead ... or a trigraph like the <igh> in light.)

Phonics = the relationships between individual speech sounds (phonemes) and the letters (graphemes) which represent these sounds.

Orthography = the spelling system of a language

Automatic Word Recognition: Orthographic Mapping

When children are first learning to read, they must decode words in a sound-by-sound manner. This is an important phase of early reading. Some models of reading refer to the sound-by-sound method of reading as the “phonological route.”

Once a child’s phonemic awareness and phonics (letter-sound) knowledge has strengthened, and they have sounded out a given word a sufficient number of times (how many times depends on the child), that word will become “orthographically mapped.” This means that the precise order of the series of letters and the sounds they represent will be stored in long term memory. Words stored this way are processed in a part of the brain that is known as the “Visual Word Form Area” or the brain’s “Letterbox.” This is an area of the brain that prior to reading, was used for faces, and we have to retrain it and restructure it to be attuned to words. Once a word is orthographically mapped, a child will be able to recognize the word instantly “on sight.” Some models of reading refer to this type of reading as via the “lexical” or “orthographic” route.

This is precisely what we want - automatic word recognition. But paradoxically, children must read a word many times via the sounding-out method before it will be properly orthographically mapped as a permanent automatic “sight word.” The brain must learn to process all the letters and sounds rapidly, in parallel, and this takes time. Sidenote: Be aware that the term “sight word” has different definitions in different reading programs.

Readers who have vision problems or visual processing issues may continue to have difficulty reading words that they have already orthographically mapped, particularly when they are doing passage reading. This can occur when the visual processing system scrambles the letters they are reading, so that the words are not received correctly in the child’s brain. While the science is not settled, there is a growing understanding amongst researchers that there are likely subtypes of dyslexia, each of which involve deficits in specific parts of our brain’s incredibly complex reading neural network. As the language neuroscientist Stanislaus Dehaene says “there are lots of ways in which the system can go wrong.” Stay tuned for my post on Vision and Visual / Visuo-Attentional Processing Issues.

Processing Speed

Measured by: RAN - Rapid Automatized Naming

Underlying all of these systems is our processing speed. How fast we are able to process information can have a significant impact on our ability to read. One common assessment used to measure processing speed is "Rapid Automatized Naming" or RAN. Basically, this is a test in which you must name a series of colors, objects, letters, or numbers printed on a sheet as fast as you can.

Readers with low RAN are more likely to struggle with fluency and reading comprehension even after they have well developed phonics, phonemic awareness, and decoding skills.

While current research suggests that RAN cannot be significantly altered, with help, students with low RAN can reach an adequate reading rate. Read more about low RAN and reading intervention here.

Further Reading: How the Brain Learns to Read - Keys to Literacy | What We Know About Reading and the Brain - Reading Rockets | Models of Reading - Reading Rockets | The Science of Reading: A Primer - Amplify | How the Brain Learns to Read - What MRI Says - Nomanis | The Reading Brain - Frontiers For Young Minds | How Literacy Transforms the Human Brain - Spelfabet | Dyslexia and the Brain - IDA | Orthographic Mapping - Five from Five | Orthographic Mapping - Reading Rockets | Orthographic Mapping - Reading Universe | Orthographic Mapping - Keys to Literacy | What is Orthographic Mapping? - ISME Journal | How the Human Brain Learns to Read - Lexia |