This study investigated the comprehension of plural morphosyntactic markers and its relationship with numerical comparison abilities in children with Down syndrome (DS). It evaluated 16 Spanish-speaking children with DS (mean verbal mental age = 3;6) and 16 typically developing children with similar receptive vocabulary (mean chronological age = 3;5). Children participated in two preferential looking tasks assessing their abilities to map singular and plural markers to their visual referents and to distinguish one object from more than one. Results showed that both groups of children correctly mapped plural markers to their referents but failed to map singular ones. Furthermore, results also indicated that both groups also looked at collections of more than one object with four objects but not at those with two. The eye movement patterns of children who looked at collections of more than one object suggest a counting-like strategy. These results indicate that comprehension of plural markers of children with DS is similar to that of their typically developing peers; however, it is not related to their numerical abilities.

The purpose of this study was to investigate sub-lexical segmentation in Spanish-speaking children based on the perception of regular syllables (pseudomorphemes), as well as their association with a visual referent. Both of these skills are the precursors to learning morphology for language acquisition. Twenty-three 12-month-old children participated; they were evaluated with three experimental tasks which tested their skill at segmenting pseudomorphemes from a set of pseudowords when they did and did not appear in the final position, as well as the association between them and a visual referent. The results showed that the children were able to segment the pseudomorphemes at the end of the pseudowords and tended to associate them with a visual referent. We also found that when the morpheme did not necessarily appear in the final position, the children who preferred that position looked at the referent for a longer time. These results reveal the skills that the children are developing on their way to learning morphology. RESUMENEl propósito de este estudio fue investigar la segmentación subléxica en infantes hispanohablantes a partir de la percepción de sílabas regulares (pseudomorfemas), así como su asociación con un referente visual, ambas habilidades como precursoras en el aprendizaje de la morfología para la adquisición de la lengua. Participaron 23 infantes de 12 meses de edad, evaluados con tres tareas experimentales, donde se puso a prueba su habilidad para segmentar pseudomorfemas, de un conjunto de pseudopalabras, cuando aparecían en la posición final y cuando no; así como la asociación entre estos y un referente visual. Los resultados mostraron que los infantes pueden segmentar los pseudomorfemas al final de las pseudopalabras y que, tienen una tendencia por asociarlos con un referente visual; igualmente, se encontró que, cuando el morfema no necesariamente aparece en posición final, aquellos bebés que prefieren esta posición miran por más tiempo al referente. Estos resultados dan cuenta de las habilidades que los infantes van desarrollando en su camino hacia el aprendizaje de la morfología.