10/15/2026
What is developmental language disorder and how is it related to dyslexia? I have my special education majors learn about this topic because DLD is often not discussed a lot with teachers as it’s handled by SLPs.
First, let’s define what DLD is. According to Drs. Suzanne Adlof and Tiffany Hogan: “Children with DLD have an unexpected deficit in language abilities despite adequate environmental stimulation and cognitive abilities with no neurological impairments” This means that DLD is not caused by a brain injury or intellectual disability.
They note that the definition for dyslexia is similar. DLD and dyslexia both have an unexpected deficit along side good environment. This shows up as good teaching for those with dyslexia and good language environment for DLD. This allows us to rule out the environment as a reason for the deficit.
What are signs of DLD?
For kids in school, this can look like not being able to follow multi step directions, telling stories that are not organized or with missing details, not using complex sentences, and struggling to pick up spoken grammar rules.
How do they overlap?
The picture below shows the current model of thinking about dyslexia and DLD. The authors state that “Panel c depicts the fully distinct hypothesis, in which dyslexia and DLD are fully distinct disorders, with different underlying deficits. This model was supported by data from a large sample of children drawn from an epidemiologic study investigating the prevalence of DLD (Catts et al., 2005) and has been supported in numerous follow-up studies (e.g., Adlof et al., 2017; Bishop et al., 2009; Fraser et al., 2010; Ramus et al., 2013). Children who are referred to in studies as “poor comprehenders” display poor reading comprehension despite adequate word reading abilities. Studies indicate that approximately one third of poor comprehenders met the standard diagnostic criteria for DLD (Adlof & Catts, 2015; Catts et al., 2006; Nation et al., 2004). The remaining two thirds exhibited moderate deficits in vocabulary, syntax, and discourse, although they did not qualify as having DLD.”
This means “that DLD and dyslexia are fully
distinct and separate disorders that frequently co-occur, with dyslexia characterized by
phonological deficits and DLD characterized by language deficits outside the phonological domain.”
The researchers point out that even if those with dyslexia do not have DLD, they still may have weak language skills compared to their peers without dyslexia. Overall, they state that half of students with reading disabilities may also co-occur with DLD.
I found this paragraph pretty great. “Milani, Lorusso, and Molteni (2010) found that children with dyslexia who were provided audiobook versions of their school textbooks showed a significant improvement in reading skills and a significant reduction in emotional or behavioral problems (as measured by parent report) over a
5-month period, relative to a control group who received only printed texts. The authors hypothesized that the audiobooks may have enhanced students’ independence, therefore leading to the reduction in emotional and behavioral problems. In addition to compensatory techniques such as audiobooks, educators can also cultivate a lifelong love for reading and learning by helping children find books that match their interests and expand their knowledge of the world around them.”
What does this mean for parents of kids with dyslexia?
Always ask for an evaluation from the SLP alongside a dyslexia evaluate by a school psychologist.
DLD and Me will be hosting a webinar on October 15 for DLD Awareness Day. Check out their website for more information.
