Dyslexia

Understanding Dyslexia

Dyslexia is not some magical thing. It is simply a word that is synonymous with difficulty in learning to read. It is sometimes referred to as a reading disorder or a specific learning disability, but they all mean the same thing. Contrary to popular myth, dyslexic folks do not see things backwards, rather in an overwhelming majority of people with a reading disorder, the problem results from a difference in how the brain processes and deals with phonological information. The very well-known problem with visual reversals, such as b/d, results not from seeing things differently but from the child's inability to retrieve the correct verbal labels for these sounds. Dyslexia is just another word for a specific learning disability in reading. Many of us choose to continue to use the word dyslexia because most of the research that has been done on reading problems for decades uses this word.

It is important to realize that there are many underlying neuropsychological problems that contribute to dyslexia or reading problems. First, it is important to understand that reading is not hardwired into our brains – like language is -, rather it is a learned skill. There is no gene for reading in your DNA. What is required in order for your brain to learn how to read is that many different substructures within the brain have to be working just right to accomplish this incredibly complex task. It is possible that genes or a combination of genes can affect how well these substructures within the entire reading network do their jobs. Therefore, we often see a genetic component to dyslexia - it often runs in families.

All of us are “wired” for language, but to learn to read we must use older structures with vision, language and especially phonological processing and rearrange the way we use them. Boy, this is hard to do!

Let's take a trip through the brain to find out what you have to do to read and understand a single word. First, the printed word is interpreted in the visual area of the brain (occipital lobe) and a specific portion of the brain referred to as the visual word form area. Thus, begins a journey requiring numerous connections to other areas of the brain which specialize in certain processes. This constitutes an entire network of connections that have to work efficiently for the word to be processed. Connections must be made to the angular gyrus, an area particularly attuned to making symbol and sound associations.

Travels continue forward in the brain to auditory centers, language centers and areas of the frontal lobe that provide meaning to the word being read. These connections are reciprocal – that is – connections travel both ways. The cerebellum is also involved as a support system for many of these functions. In addition, frontal areas are activated to assure that appropriate attention and understanding may occur in the process and that the child can self-monitor his or her understanding.

Not only must all of these areas be working adequately to perform the necessary task but the connections need to be fast and become automatic. (One area of the brain particularly involved with this automaticity is the insula).

From this journey through the brain for reading just “one word” it is readily apparent that a breakdown in any of these areas, connections or processes can contribute to reading problems. That is why it is essential to investigate all possible components of neuropsychological processing to really understand what is happening when a particular student is experiencing reading difficulty so that targeted intervention for their particular needs can be designed and implemented. Without question, almost all reading researchers will tell you that the "one-size-fits-all" teaching techniques used in many schools cannot meet the needs of students with dyslexia.

Every child is an individual and every child with dyslexia is an individual bringing a combination of notable talents and strengths to the table along with specific processing breakdowns in the overall reading network. For example, many students with dyslexia have very strong visual-spatial abilities, creative thinking and reasoning skills and think in a way that leads to invention and innovation. Many of our most revered artists, thinkers, inventors, financial builders and architects, to name a few professions, have had dyslexia and have used their talents and strengths to better our world. However, most had to suffer through periods of school time where they felt different, sometimes felt like a failure and had their talents under appreciated.

All the research on dyslexia tells us that we can and should identify students at risk for reading failure (dyslexia) in kindergarten and first grade. All the research also reports that early intervention needs to be targeted to specific areas of weakness and done directly and explicitly. This direct intervention needs to be of sufficient duration, reflect high quality instruction, and be provided by a highly qualified and trained teacher.

The two best predictors of whether a child will have reading problems are difficulty with phonological awareness and naming speed/automaticity problems. Children who have problems with phonological awareness will have difficulty initially being able to decode words. Children with only naming speed/automaticity problems may learn to decode words adequately but will be very slow in the process. The slowness will contribute to later reading comprehension problems for these children. Children who have both deficits are most at risk for dyslexia of a significant degree. If students add a language/vocabulary problem to the mixture, they will have even greater difficulty and experience problems with both decoding and reading comprehension, often to an even greater degree.

Other strong predictors of reading efficiency in the young child include:

Facility with naming letters

Facility with letter-sound correspondence

Rhyming ability

With our trip through the brain, it is easy to see that dyslexia has many forms and the intervention appropriate for a particular child depends on what that child brings to the table. Some children have only subtle deficits which may involve fluency initially and comprehension later on and some children have multiple areas of deficit that require very extensive and intensive remediation. Most dyslexic children (English speakers) begin with decoding problems and real trouble learning the rules of grapheme-phoneme correspondence which shows up as problems in reading, spelling and writing.

It is also important to realize that all children are not ready to read at the same time although the way schools are structured doesn't take this into account. For example, girls tend to have more facility with language and vocabulary in the early years than boys. In addition, girls are faster than boys until around the age of 8 on many timed naming tasks. If the child had rich exposure to language, vocabulary and oral expression before entering school, this child is much better able to make connections with text. But if they did not, they are at great disadvantage when faced with the task of learning to read and comprehend. The most important factor is early diagnosis and intervention. Dyslexia can be diagnosed at age 6 and younger students can be screened for early problems with phonological processing and language development.

For those of you with a science inclination - you may be interested in some of the most recent research findings about dyslexia: (if you are not - just skip this section)

Some researchers have found considerable differences in the speed of processing visual information in dyslexia. Think of an image of a star followed quickly by another image of a star. In the brain of many individuals with dyslexia, two rapidly presented visual "flickers" appear fused into one stimulus, because the person cannot process this visual information quickly enough. Some individuals with dyslexia have the same timing mechanism problem with auditory stimuli.

Researchers found that the left angular gyrus region that good novice readers draw upon appears functionally disconnected from the other left hemisphere language regions during reading and the processing of phonological information in dyslexics.

Researchers using MEG (magnetoencephalography) found that children with dyslexia move from visual regions in the left and right occipital lobes to the right angular gyrus region and then to their frontal areas - this is an entirely different reading circuitry than is usually seen in typically developing readers.

Researchers have found a disconnection between frontal and posterior language regions, based on under activity in an expansive connecting area called the "insula" - an area critical for automatic processing

Other researchers have found that people with dyslexia use more right-hemisphere regions, including the occipital-temporal regions and have underactivated left posterior regions typically used by normally developing readers.

So what are some of the potential "causes" for dyslexia:

A developmental, possibly genetic flaw in the structures underlying language, auditory or visual processing (e.g. a failure of working groups to learn to specialize within the structures)

A problem in achieving automaticity - in retrieving representations within given specialized working groups or in the connections among structures in the circuit, or both

An impediment in the circuit connections between and among these structures

The rearrangement of a different circuit altogether from the conventional one used for particular writing system (e.g. right hemisphere takes over)

Now translating the neuroscience to the classroom,

Learning to read is like forming many different threads into a rich and vibrant tapestry. If the different threads are not weaved and connected just right, the tapestry may ravel and need to be repaired. If the individual threads are not strong enough, they need to be reworked and built up by reinforcing them with supports. Take a look at the following graphic which details the contributing “threads” to the process of reading.

In a neuropsychological evaluation all of these threads will be examined along with many other processes along with emotional/behavioral functioning factors that can impact the student. Once the “targets” are identified, very specific strategies can be developed for the individual needs of the child. Parents and teachers need to know exactly what to target, the actual strategies that will be effective and commercial resources that may be helpful. Although reading is complex – it can be made easier to understand. We just need to take a close look at each child experiencing difficulty and map out the road to follow.

Lynda Boucugnani-Whitehead, Ph.D.

Neuropsychologist

CEO Strategic Learning Connections, Inc.