Declarative and Sequential learning in Spanish-speaking children with Language Impairment

Language Impairment (LI) is a developmental disorder that mainly manifests impaired language learning and processing. Evidence, largely from English-speaking population studies, has shown that children with LI compared to typically developing (TD) children have low scores in sequential learning tasks but similar performance in declarative learning tasks. According to the declarative/procedural model, LI children compensate for their deficiency in syntactic skills (i.e., deficits in the procedural memory system) by using the declarative memory system (indispensable for vocabulary acquisition). Although there are specific deficits in children with LI depending on the language they speak, it is assumed that this model can explain the shortcomings of such pathology regardless of the language spoken. In the current study, we compared the performance of fifteen school-aged Mexican Spanish-speaking children with LI and twenty TD children during sequential and declarative learning tasks and then analyzed the relationship between their performance in these tasks and their abilities in syntax and semantics. Children with LI displayed lower scores than normal children in the sequential learning task, but no differences were found in declarative learning performance with verbal or visual stimuli. No significant correlations were observed in children with LI between their performance in sequential learning and their abilities in semantics and no significant correlations were observed in TD children between their performance in sequential learning and their abilities in syntax. In contrast, for children with LI, a significant correlation between their performance in declarative learning and their abilities in semantics was observed and for the group of TD children a significant correlation between their performance in declarative learning and their abilities in syntax was observed. This study shows that Spanish-speaking children with LI display a pattern of learning impairment that supports the declarative/procedural model hypothesis. However, they display poor verbal declarative learning skills, probably due to low verbal working memory capacity.