By Gordon Sherman, Ph.D.
Brains of people with dyslexia are different in many ways. Starting early in life, the language network and certain sensory systems develop along a unique trajectory. It is the interaction between genes and environment that modifies the development of these systems, producing a distinctive learning profile we call dyslexia. Dyslexia varies from individual to individual in the combination and degree of strengths and weaknesses due to the intricacies of brain development and countless environmental variables. Dyslexia is lifelong but amenable to educational intervention.
How does this neuroscientific view of dyslexia inform teaching of children and adults with this learning disability? Let's explore the interaction of these brain-based differences with the environment.
In dyslexia, the cortical language network of the brain is a network distinctly different in appearance, organization, and function. These differences probably account for the fact that most people with dyslexia need direct instruction in phonological processing (producing/interpreting language sound patterns) and in alphabetic skills (written symbols representing speech). Weak phonological and alphabetic skills set the stage for a complex set of consequences, including difficulty learning to read, write, and spell.
Another difference involves the sensory nuclei of the thalamus. There are smaller nerve cells in lower-level visual and auditory processing centers that may affect processing of fast information - like flashing pictures or rapidly presented words or sounds. (Some findings link a deficit in fast processing with severe language difficulties, although this hypothesis is controversial.)
Clearly, brains with atypical language and sensory systems are at a disadvantage in a traditional educational environment, where fast-paced, linguistically loaded instruction prevails.
Another brain-based condition, Attention-Deficit/Hyperactivity Disorder (AD/HD), may exacerbate dyslexia. Motor, attention, and arousal systems differ in many people with dyslexia. Add increased impulsiveness, distractibility, and hyperactivity to modified language and sensory systems and big challenges can ensue, particularly in learning to read.
Achieving success with dyslexia, especially when combined with AD/HD, can be a circuitous and uphill struggle. Nevertheless, people with this learning disability often excel in life. Almost always, though, their stories involve painful struggles with the educational system - where most dyslexic brains function as square pegs in round holes. Not because they are inferior, as the achievements of people with dyslexia attest, but because the peg and hole do not always match.
The point here is subtle but important - the environment can render the learning difference a learning disability. Far from an esoteric or semantic distinction, this scientific perspective informs enlightened educational planning and policy, illuminating solutions and reasons for implementing them. Dyslexia is an example of human brain variation. Human diversity is more than a politically correct concept. Diversity propels evolution by permitting adaptability to various environments. History and science tell us that environments inevitably change and that brain diversity may benefit our species.
This is not to say, however, that dyslexia is a minor learning problem or some inconsequential blip falling within the normal range of variation. Parents and educators alike must recognize that dyslexia is a distinctly different brain organization that can be profoundly disabling, particularly in the context of a poorly designed educational environment.
So, how do we modify the educational setting to prevent a distinct difference from becoming a profound disability? How do we design educational environments to reduce struggles, capitalize on strengths, and maximize success for people with dyslexia - enabling them to contribute their abilities and talents?
You might be surprised to learn we already have answers to these questions and the answers benefit all learners.
While there is no cure for dyslexia (efforts to cure it may be misguided anyway), effective approaches for teaching reading and writing skills to children with dyslexia do exist. These research-based approaches incorporate several critical components. They deliver a structured-language curriculum in a sequential, systematic, and cumulative way - offsetting language, sensory, memory, and motor/attention processing differences. More specifically, these approaches provide explicit instruction in phoneme awareness, phonics, reading fluency, vocabulary, and reading comprehension skills. All of these are fundamental to becoming a proficient reader.
Indeed, reading research tells us effective early literacy instruction for all children includes these elements. All children benefit from well-informed instruction in phonics, comprehension strategies, language development, and writing skills, as well as from exposure to rich fiction and nonfiction literature.
This is not to say an eclectic mix of code-based and meaning-based teaching equals effective reading instruction. Unfortunately, in classrooms across the country, "balanced reading instruction" has been interpreted as a dash of this and a dollop of that, or as equal focus on phonics and whole language. Since many teachers have more experience with whole language and less expertise in structured language, the resulting hybrid usually skews toward whole language (which minimizes structured-language teaching in order to preserve focus on meaning). More often than not, the eclectic mix does not meet the standard of the research-based, systematic, structured-language teaching recommended for all students, particularly for beginning readers.
All brains can suffer disabling consequences from poor instruction. However, those that depend most on effective teaching are penalized most severely. Students with learning difficulties and others at risk for failure or underachievement pay the highest price for poor teaching. Effective instruction in general education classrooms in early grades is vital for children with dyslexia because most do not receive special education services until after second grade, after they have failed to learn to read. The good news is we can prevent this failure for many.
Clearly, circulating the scientific evidence about what constitutes good instruction is not enough to guarantee children will receive it. The need to understand the dynamics of school change is becoming obvious as educators and policy makers attempt to implement research-based knowledge about effective instructional practices. So, too, is the critical need to impart the essential competencies to teachers through preservice and inservice teacher preparation programs. Teacher attitudes and knowledge, including how the English language is constructed, are fundamental to implementing effective instruction.
To recap, processing differences in multiple brain systems cause fundamental difficulties in acquiring phonological and alphabetic skills. Weaknesses in these skills set the stage for academic problems in areas such as decoding, fluency, comprehension, written expression, and spelling. These problems, in turn, can lead to various negative educational and social consequences.
Fortunately, while dyslexia is brain-based and lifelong, we can prevent and diminish reading disabilities and forestall associated academic problems. The educational environment plays a key role. It can translate a distinct way of learning differently into a profound learning disability. Or it can offset neural processing weaknesses and encourage latent strengths to blossom into competencies and talents. A structured-language curriculum delivered through explicit, sequential, systematic, and cumulative instruction by highly skilled teachers is a critical component in an optimal learning environment, particularly in the early grades.
Happily, designing educational environments to enhance learning for children with dyslexia benefits all learners. However, changing these environments in order to initiate, nurture, and sustain effective teaching is challenging. Implementing effective instruction depends on teacher competencies and requires understanding of the complex dynamics of school change.
Other articles in this series will discuss multisensory instruction, early intervention, and the ways the environment actually alters brain function. In the meantime, try thinking about dyslexia from a neuroscientific perspective. Dyslexia is neurologically based. It can be disabling, particularly in the context of a poorly designed and heavily text-oriented educational setting. The environment determines the extent of the disabling consequences. Changing the environment can prevent or diminish a disability.