By Wendy C. Georgan, Ph.D. and Tiffany P. Hogan, Ph.D., CCC-SLP
MGH Institute of Health Professions
"Neurodevelopmental conditions" is a name doctors and scientists give to differences from the expected brain and behavior development during childhood. There are many ways that brain development can be different. One of the most well known neurodevelopmental conditions is autism, which has some similarities with Developmental Language Disorder (DLD), but also some important differences. Developmental language disorder (DLD) is the term many researchers use to describe children who have unexplained difficulties with spoken language. However, there are many other terms used to describe the same disorder. This is partly because children with DLD have been of interest to many research disciplines. From psychology and linguistics to neuroscience and genetics, researchers have used different terms for children with DLD. In addition, the terms used by researchers are different from those used by clinicians and educational policymakers. This is not only confusing for parents and educators of children with DLD, but also makes it hard for researchers to collaborate and generate awareness of DLD when not everyone is using the same terminology.
In light of this issue, it is helpful to know what other terms are being used to refer to DLD. The terms have been broken down into three categories: research terms, clinical terms (including terms used for insurance purposes), and educational policy terms.
Developmental Aphasia or Dysphasia
The term “developmental aphasia” was one of the first used to describe children with difficulties in language production and comprehension. Popular in the 1950s, this term is no longer commonly used because of the misleading comparison to adult aphasia, which is caused by brain injury (DLD is not).
Specific Language Impairment (SLI)
One of the most widely used terms in current research. In principle, this refers to children who have DLD with “normal” nonverbal IQ scores. In reality, the criteria for “normal” nonverbal intelligence varies among research groups. To fully access the research literature on DLD, one should also review the literature on SLI.
Primary Language Impairment (PLI)
While this term is meant to emphasize that language is the primary impairment, it is often interpreted in different ways (and in the UK, it gets mixed up with “primary” as in “primary school”!). PLI can also be confused with an abbreviation for Pragmatic Language Impairment.
Language Learning Impairment (LLI)
This term places an emphasis on the fact that children with DLD have difficulties learning language. While more education-friendly than some other research terms, it is less popular.
Developmental Language Disorder (DLD)
DLD is currently a preferred term for language production and comprehension problems that emerge early in development and that have no known cause. Like developmental aphasia, it does not refer to a language problem caused by a brain injury; like SLI, it does not refer to a language problem that is associated with an intellectual disability. Like PLI and LLI, it refers to a difficulty learning language that is the only or primary problem affecting the child.
In clinical practice, the different labels mainly come from the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). Under the communication disorders subsection of “neurodevelopmental disorders,” there are two terms that a child with DLD could be given:
This refers to children who have difficulties with vocabulary, sentence structure, and/or discourse.
Specific Learning Disorder
This refers to children who have difficulties with reading, writing, or math whether they have deficits in spoken language or not. However, since spoken language is critical for learning to read and write, children with DLD could be labeled as having specific learning disorder.
In the U.S., some insurance companies will cover some of the costs of diagnosing and treating DLD; however, these companies will use different terms from any of those listed above. To bill insurance, your clinician will need to list an ICD-10 code. The codes most likely to encompass DLD are F80.1 Expressive language disorder or F80.2 Expressive and receptive language disorder.
In U.S. educational policy, the Individuals with Disabilities Education Act (IDEA) has its own names and categories of disabilities. There are three IDEA terms that a child with DLD could be given:
This includes children with delays in language acquisition. This term is typically used in educational settings that serve children birth to eight years old.
Speech or Language Impairment
This includes children with a communication disorder, including language impairment, that affects their educational performance. This term can also be abbreviated as SLI or S/LI, which is not to be confused with Specific Language Impairment.
Specific Learning Disability
Not to be confused with the DSM-5 label “Specific Learning Disorder,” this educational term refers to children with trouble understanding or using spoken or written language, which affects their reading, writing, spelling, math, or other areas.
Educational labels are particularly important because they are the basis for determining whether your child qualifies for intervention services and accommodations in school. Of note, educational labels can differ by country.
All of these terms could potentially be used to describe a child with DLD. Because of this, there has been a worldwide push to decide on a common term. Fueled by the CATALISE Consortium (Bishop et al., 2016), “developmental language disorder” is becoming more and more prominent as the preferred term. As research in DLD continues to move forward, having a common term will help bring together the many researchers, clinicians, and educational policymakers who want to support children with DLD.
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing.
Bishop, D. V., Snowling, M. J., Thompson, P. A., & Greenhalgh, T. (2016). CATALISE: A multinational and multidisciplinary Delphi consensus study. Identifying language impairments in children. PLOS one, 11(7). doi:10.1371/journal.pone.0158753.
Individuals with Disabilities Education Act, 20 U.S.C. §§ 1400 et. seq. (2004).
Leonard, L.B. (1998). Children with specific language impairment. Cambridge, MA: MIT Press.
Reilly, S., Bishop, D.V.M., Tomblin, B. (2014). Terminological debate over language impairment in children: forward movement and sticking points. International Journal of Language & Communication Disorders, 49(4), 452-462.
Sun, L. and Wallach, G.P. (2014). Language Disorders Are Learning Disabilities: Challenges on the Divergent and Diverse Paths to Language Learning Disability. Topics in Language Disorders, 34(1), 25-38.