Understanding how children learn to read requires a comprehensive understanding of language, phonology, cognition, and environmental factors. While phonological processing deficits have long been considered central to dyslexia (Snowling, 2000; Vellutino et al., 2004), growing evidence suggests that reading difficulties can emerge from multiple developmental pathways, influence by a diverse combination of risk and protective factors (Hulme & Snowling, 2016; Catts et al., 2017). These individual differences underscore why some children struggle primarily with decoding, others with comprehension, and many with both.
Language as a Foundation for Literacy Development
Oral language provides the conceptual, syntactic, and semantic base upon which reading skills are built. Children with difficulties in oral language may struggle with vocabulary, grammar, narrative ability, and inferencing — all critical for comprehension (Nation, 2019). Research consistently suggests that language ability in the preschool years predicts later reading comprehension and broader academic achievement (Bishop & Snowling, 2004; Snowling & Hulme, 2021). Although phonological processing deficits remain a core feature of dyslexia, many children at risk show broader language weaknesses before formal reading instruction begins (Hulme et al., 2015). These early difficulties influence the development of decoding, reading fluency, and comprehension. Children with Developmental Language Disorder (DLD) are at particular risk: approximately 50% experience reading comprehension difficulties and many also struggle with word reading (Catts et al., 2005).
Oral language provides the conceptual, syntactic, and semantic base upon which reading skills are built.
Multiple Developmental Pathways to Reading Disorders
Traditional models often treated dyslexia as a primarily phonological disorder. However, recent evidence supports a multiple-deficit framework, in which phonological, oral language, cognitive, and environmental influences jointly predict reading outcomes (Pennington, 2006). Key pathways include:
1. Phonological Pathway
Characterised by deficits in phonological awareness, rapid naming, and phonological memory. Strongly associated with dyslexia (Snowling, 2000; Ramus et al., 2013).
2. Oral Language Pathway
Weak vocabulary, grammar, and broader language skills impair decoding, text integration, and comprehension (Nation, 2019). Children entering school with poor language skills are at increased risk for both reading and mathematics disorders (Snowling & Melby-Lervåg, 2016).
3. Mixed or Multiple-Risk Pathway
Many children show both phonological and oral language weaknesses, with more severe and persistent reading difficulties (Hulme & Snowling, 2016).
4. Environmental and Instructional Factors
Home literacy environment, socioeconomic disadvantage, and instructional quality contribute to individual trajectories (Stuart et al., 2008).
Longitudinal studies show that for children who begin school with poor language, difficulties accumulate over time: word reading lags behind, reading comprehension weakens, and academic vulnerability increases. These patterns are consistently associated with later mental health challenges such as anxiety, low self-esteem, and school disengagement (Carroll et al., 2005).
Screening and Early Identification
Effective early identification, pivotal to helping young children, should assess:
- Oral language (vocabulary, grammar, narrative skills)
- Phonological awareness
- Rapid automatized naming (RAN)
- Letter–sound knowledge
- Working memory and processing tasks
- Response to early instruction
Screening language skills is especially important, as language weakness often predates and predicts literacy difficulties across multiple domains (Bishop et al., 2017).
Protective Factors and Educational Interventions
Despite the presence of developmental risk, targeted educational experiences can support more positive trajectories. Protective factors include:
- High-quality early language environments
- Systematic phonics instruction
- Explicit teaching of vocabulary and oral language structures
- Early intervention programmes such as oral language enrichment and structured literacy instruction (Snowling & Hulme, 2021)
Children with DLD or language vulnerability respond best to interventions that explicitly target vocabulary, narrative skills, phonological skills, and comprehension strategies (Melby-Lervåg et al., 2020). Educational systems integrating early screening, language-focused instruction, and structured literacy approaches are best positioned to reduce long-term reading difficulties.
Despite the presence of developmental risk, targeted educational experiences can support more positive trajectories.
Conclusion
Current evidence signals that reading disorders aetiology is associated with multiple developmental influences rather than a single phonological deficit. While phonological skills remain essential for early decoding, oral language provides the broader conceptual and linguistic foundation for comprehension and academic success. Children who enter school with language difficulties are at higher risk for decoding and comprehension difficulties but also for challenges in mathematics, wider learning, and emotional well-being. A comprehensive approach is therefore needed, one that considers oral language, phonology, cognitive processing, and instructional context. Early screening, combined with high-quality language environments and structured literacy instruction, can act as protective factors that mitigate risk and support more positive developmental trajectories.
Where next?
We are lucky to have one of the Titans, Professor Maggie Snowling, deliver a webinar on the role of language in literacy development, and address the specific challenges faced by children with language disorder. Full details can be found at Rethinking reading disorders
References
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Bishop, D. V. M., Snowling, M. J., Thompson, P. A., Greenhalgh, T., & the CATALISE Consortium. (2017). Phase 2 of CATALISE: A multinational and multidisciplinary Delphi consensus study of problems with language development. Journal of Child Psychology and Psychiatry, 58(10), 1068–1080.
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