* Long History of Recognition: Difficulties with language acquisition have been observed and documented for centuries. However, early understanding was often based on broad categories like "mental retardation" or "learning disability."
* Shift to a Specific Disorder: The concept of SLI as a distinct disorder began to emerge in the late 19th and early 20th centuries. Researchers started noticing patterns of language difficulties in children who were otherwise intellectually normal.
* Terminology Changes: The term "Specific Language Impairment" itself was not widely used until the 1980s and 1990s. Prior terms included "developmental language disorder" and "language-learning disability."
* Ongoing Research: SLI is a complex area of study, and our understanding continues to evolve. Researchers are still working to determine the underlying causes, develop effective interventions, and improve diagnostic tools.
Key Milestones:
* 1861: John Langdon Down publishes a description of children with cognitive challenges, including some with language difficulties.
* 1904: Helen Thompson Woolley publishes a study on the language abilities of children with mental retardation, noting that some children have significant language delays despite normal intelligence.
* 1970s-1980s: The term "Specific Language Impairment" gains traction, highlighting the specific nature of the disorder.
Instead of a single "discovery," we can say that SLI emerged as a distinct category over time through ongoing research and a shift in understanding language disorders.