A Comprehensive Model for Understanding Reading Disabilities

A Comprehensive Model for Understanding Reading Disabilities
Danielle Scorrano

Each school year invites a vibrancy that is only truly understood by those who enter the teaching profession. Students enter the classroom each day with diverse needs and skills, coupled with the shared eagerness to participate in a shared class community. At Windward, the community understands the magnitude of the endeavor that lies ahead for our students each day – to engage in a rigorous learning environment to develop the reading, writing, and language skills that are most difficult for them. As students learn new skills, their brains create new neural pathways for further learning. Yet, each child’s development is both unique and individual. 

A Windward student’s experience in the classroom illustrates the research on children with language-based learning disabilities and effective practices to support their academic growth. If you imagine a brain, we know that this incredible organ is intricate based on a person’s neurological and genetic makeup, and it is constantly being stimulated with new connections as students learn about new ideas. This theory, neuroplasticity, is perhaps one of the most important concepts in educational neuroscience, and it is foundational for teachers in the classroom. Similarly, researchers explore brain plasticity when they study how children’s brains develop throughout a learning experience. 

The increased knowledge that scientists gain about the brains of students with language-based learning disabilities, such as dyslexia, continues to inform classroom practice. As a result, students like those at The Windward School receive effective, scientifically based instruction in a rigorous learning environment so they can successfully develop the reading, writing, and language skills that are most difficult for them. This article focuses on the cumulative risk and protection model of dyslexia (Catts & Petscher, 2020) and how we can integrate the research foundation presented by Hugh Catts, PhD, (who will be speaking at The Windward School’s 2021 Robert J. Schwartz Lecture) with practical insights to better inform educational practice. 

The increased knowledge that scientists gain about the brains of students with language-based learning disabilities, such as dyslexia, continues to inform classroom practice.

The Complexity of Reading and Reading Difficulties 
Before examining the multidimensional nature of reading difficulties, it is necessary to understand the complexity of the reading process. Examining the theory of neuroplasticity further, it posits that the brain is not hardwired for reading written text, but the brain’s circuitry reorganizes as a learner builds skills for reading (Dehaene, 2010; Seidenberg, 2017; Wolf & Stoodley, 2007). Consequently, reading is an effortful, deliberate task requiring the integration of numerous cognitive skills. In their model of skilled reading acquisition and comprehension, Gough and Tunmer (1986) developed the Simple View of Reading, which has been cited across bodies of research for decades (Catts, 2021). The Simple View of Reading outlines two groups of skills necessary for reading mastery—word level decoding and language comprehension (Gough & Tunmer, 1986). 
 
Reading is an effortful, deliberate task requiring the integration of numerous cognitive skills.
 
While Gough and Tunmer’s (1986) model provides a foundational overview, later research shows the nuanced and complex nature of skilled reading (Catts, 2018). For example, the seminal Scarborough Reading Rope (Scarborough, 2001) details the skills required for reading as fibrous strands of a rope, each integral for strengthening the metaphorical rope of reading. Scarborough’s (2001) model expands upon Gough and Tunmer’s (1986) earlier conceptualization of word-level and language skills. Scarborough (2001) defines word-level skills to include phonological awareness, decoding, and mastery of sight words. Language comprehension skills involve vocabulary, structures of language like grammar and syntax, verbal reasoning, background knowledge, and skilled identification in literary structures (i.e., recognizing narrative or expository text structures) (Scarborough, 2001). Oral language skills also require the understanding of meaning, from words to sentences (Adlof & Hogan, 2019). In order to achieve reading fluency and comprehension, a reader must build automaticity and fluency at the word level while developing competence in language skills (Scarborough, 2001). 

The theoretical frameworks and related research on reading provide insights on why children vary in their mastery of this cognitive skill. Research supporting the Simple View of Reading, for example, implies that decoding and word-level difficulties attribute to a variation in reading in the earlier grades, while difficulties related to language comprehension skills lead to differences in reading in the later grades (Catts, 2018, 2020). Further research on the dynamic nature of the brain and its plasticity points to multifaceted and interdependent factors that relate to variation in reading mastery amongst children. When Devin Kearns, PhD, delivered the 2019 Fall Community Lecture at The Windward School, he synthesized the research associated with reading difficulties (including primary deficits in phonological awareness and word reading), oral language, background knowledge, syntax, and vocabulary (Kearns, 2019). Other influences of reading difficulties could include insufficient early exposure to rich language, inadequate reading instruction, attention, or behavior (Kearns, 2019). It is important to note that these factors should not be misinterpreted as a single cause of a reading difficulty, rather that they could attribute to or increase the probability of a developing reading difficulty.  

Cumulative Risk Factors of Dyslexia 

In examining the factors of the emergence of dyslexia, Catts and Petshcer (2020) developed the cumulative risk and protection model. While strong evidence points to the dominance of certain deficits in dyslexia, a model that denotes a single cause may not account for the variability in some children with dyslexia (Catts & Petscher, 2020). Instead, the cumulative risk and protection model encompasses a multifaceted approach, characterized by the integrated and interdependent nature of the brain (Catts & Petscher, 2020). 

The interaction between certain risk and protective factors encompasses the probability of risk for developing reading deficits (Catts & Petscher, 2020). Risk factors, both neurobiological and environmental, increase the likelihood of a child experiencing difficulties learning to read. Decades of evidence point to the strong presence of risk factors of dyslexia such as deficits in  phonological and word-level reading skills, Rapid Automatized Naming (RAN), letter knowledge, and verbal working memory (Catts & Petcher, 2020; Gough & Tunmer, 1986; Gaab, 2017). Other studies show that deficits in language skills such as oral language and vocabulary (Hogan & Adlof, 2019), as well as delays in executive functioning, exacerbate difficulties experienced by students with dyslexia. Current research explores the role of the environment at home, in school, or within the larger community in the development of reading disabilities, such as childhood trauma and experiences inducing toxic stress (Catts & Petscher, 2020). 

Protective Factors of Dyslexia 

Despite the complexity of risk factors of dyslexia, Catts and Petscher’s model (2020) shows the influence of protective factors in promoting positive outcomes or resilience in children with reading disabilities. Access to high quality, evidence-based, explicit reading instruction that targets skills has been shown to powerfully reduce difficulties associated with reading disabilities like dyslexia (NICHD, 2001; Foorman et al., 2016; Torgesen, 2004). Decades of research support skills-based instruction in phonological awareness, word attack strategies, spelling, handwriting, fluency, vocabulary, and comprehension (NICHD, 2000; Foorman et al., 2016; Seidenberg, 2017; Torgesen, 2004). Snow, Burns and Griffin (1998) assert that “[High] quality classroom instruction [especially] in kindergarten and the primary grades is the single best weapon against reading failure.”  

Access to high quality, evidence-based, explicit reading instruction that targets skills has been shown to powerfully reduce difficulties associated with reading disabilities like dyslexia.

Current research examines the role of protective factors that promote social-emotional resilience, such as growth mindset and self-control (Catts & Petscher, 2020). Furthermore, it is well documented in cognitive and psychological research that positive relationships with teachers, parents, and mentors promote prosocial outcomes (Catts & Petscher, 2020; Haft, Hoeft & Myers, 2016; Haft et al., 2019). For instance, Haft and colleagues (2019) explored the role of mentoring on the social-emotional resilience of students with LD and ADHD, concluding that mentoring resulted in an increase in measures of self-esteem and a decrease in measures of depression. 

The cumulative risk and protection model of dyslexia (Catts & Petscher, 2020) comprehensively demonstrates the multifaceted nature of reading difficulties associated with this language-based learning disability. This model supports the decades of research that establishes the multidimensionality of factors influencing reading difficulties at large. Through the examination of numerous factors in the model, researchers and educators gain a better understanding of the markers and experiences that result in a child’s overall vulnerability to reading difficulties. 

Implications for Education 

As the research community gains a more nuanced understanding of dyslexia and related reading difficulties, policies and educational practices should be addressed across the system and supported at the school level. In fact, a deeper understanding of the factors associated with dyslexia and other reading difficulties has never been more critical or timely. While the calls for change outlined below are not new, they nevertheless must be prioritized for struggling readers.  

  1. Understanding what dyslexia and related reading disabilities are and are not 

Pervasive myths and misconceptions about learning disabilities like dyslexia, developmental language disorders, and other reading difficulties continue to exist throughout the world. Lack of knowledge and understanding about common learning disabilities dictate whether children receive the support and instruction they need. As a global society, we must address the lack of systemic understanding about learning disabilities, especially as they relate to literacy, in order to promote the academic success and well-being of all children. 

  1. Implementing universal screening 

The research conclusively points to universal early screening as a powerful way to mitigate risks associated with the development of reading disabilities. Early screening evaluates a child’s overall risk profile of a reading disability, identifies the factors that influence the child’s difficulties, and provides an entry point for early intervention. 

  1. Investing in an evidence-based curriculum and teacher training 

Early screening should precede an evidence-based explicit intervention that targets a child’s needs and mitigates further academic and secondary social-emotional consequences. Gaab (2017) explains, “Although a diagnosis of dyslexia usually is not given before the end of second grade or the beginning of third grade (after the requisite period of failing), intensive interventions are most effective in kindergarten or first grade.” There is an urgent responsibility for policy makers, institutes of higher education, and school leaders to understand the educational, economic, social, and moral implications of appropriately and effectively addressing the needs of our nation’s most vulnerable learners. 

There is an urgent responsibility to understand the educational, economic, social, and moral implications of appropriately and effectively addressing the needs of our nation’s most vulnerable learners. 

  1. Recognizing teachers as changemakers and scientists 

The research on supporting learners with disabilities points to the invaluable power of teachers. Educators are changemakers and scientists. As a Windward teacher, I never underestimated my power to change my students’ lives, especially when armed with a toolbox of knowledge and expertise. 

Working Toward “Yes, And” in Research and Education 

A comprehensive model for understanding reading disabilities like dyslexia must always include a “yes, and.” It requires a yes to embracing and disseminating the science that addresses the needs of students and an eagerness to learn more. It requires a yes to advocating for the policies and educational practices proven by science and the commitment to invest more. With a “yes, and” mindset, we work toward providing an exceptional learning experience, a fundamental right for all students.