A Longitudinal Exploratory Case-Series Comparing Morphological Trajectories in Four Early-Implanted Greek-Cypriot Children and Eight Typically Hearing Peers

Objectives: This paper explores whether deaf Greek-Cypriot (GC) children with cochlear implants (CIs) begin using the various forms of the definite article (DA) of the Greek language similarly to their typically hearing peers in terms of order of appearance and age. Furthermore, it explores if their MLUm growth correlates with that of typically developing peers. Methods: This is a longitudinal study with quantitative and qualitative analyses. The sample comprises four prelingually deaf GC children with CIs and eight typically hearing (TH) children with no developmental delays. Age and hearing status (CIs vs. TH) were used to explain variability in results. The effect of random effects was also examined. Presence of random effects was examined using Mixed Linear Models. Growth trajectories were plotted for in-depth result description and interpretation. Results: Both groups demonstrated a significant linear increase in their accurate usage of definite articles with age, whereas hearing status showed no statistically significant impact on any outcome measure. Individual variance among children accounted for approximately 33% to 50% of the variance in correct article production. Additionally, Mean Length of Utterance in morphemes (MLUm) values between the two groups remained correlated across all age levels. Discussion: While random individual effects influence the rate of correct production, early morphosyntactic trajectories for CI children seem to be similar to those of typically developing controls. Due to the small sample size, studies with bigger samples are needed to replicate, confirm and validate further the results of the current study.