Syntactic ability of girls with fragile X syndrome: Phonological memory and discourse demands on complex sentence use

Sara T. Kover, Leonard Abbeduto

Research output: Contribution to journalArticle


This study was designed to establish the extent of delay in complex sentence use by females with fragile X syndrome (FXS) and to identify sources of variability among individuals. Females with FXS (n = 16; 10;2–15;7) and younger typically developing girls (n = 17; 4;1–8;11) were group-wise matched on nonverbal cognition and receptive syntax. Language samples (conversation and narration) yielded syntactic complexity in terms of mean length of C-unit (MLCU) and Developmental Level sentence coding (DLevel; Rosenberg & Abbeduto, 1987). Complex syntax was not weaker than developmental expectations; however, MLCU was lower than expected for age. Phonological memory and verbal working memory correlated with measures of syntactic complexity in narration. Discourse demands may play an important role in the language produced by females with FXS.

Original languageEnglish (US)
Pages (from-to)511-534
Number of pages24
JournalAmerican journal on intellectual and developmental disabilities
Issue number6
StatePublished - Jan 1 2019



  • Expressive language
  • Individual differences
  • Short-term memory
  • Working memory

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health
  • Neuropsychology and Physiological Psychology
  • Developmental and Educational Psychology
  • Arts and Humanities (miscellaneous)
  • Clinical Neurology
  • Psychiatry and Mental health

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