Vocabulary Breadth and Depth in Adults With Developmental Language Disorder
Tingting Wang, Charlotte Hilker, Dawna Duff, Kristi HendricksonPurpose:
Developmental language disorder (DLD) affects approximately 7%–11% of children and often persists into adulthood, contributing to long-term challenges in education, employment, and health. Although vocabulary challenges are well-documented in children with DLD, relatively little is known about how these difficulties manifest in adulthood. The current study examines vocabulary knowledge in adults with DLD along two dimensions: breadth (the number of words for which an individual can retrieve a meaning) and depth (quality of semantic knowledge for known words).
Method:
Vocabulary breadth was assessed using the standardized Peabody Picture Vocabulary Test–Fifth Edition (PPVT-5), while a novel scoring system was developed to evaluate vocabulary depth in a well-documented definition task (Wechsler Abbreviated Scale of Intelligence–Second Edition [WASI-II] Vocabulary subtest). Linear regression analyses were conducted to examine group differences between adults with DLD and peers with typical language (TL).
Results:
Adults with DLD (
Conclusion:
These findings characterize the long-term development of vocabulary skills in adults with DLD and highlight the importance of considering both vocabulary breadth and depth when assessing language profiles in adulthood.