Understanding nonliteral language abilities in children with Neurofibromatosis Type 1

Objective: Neurofibromatosis Type 1 (NF1) is a genetic syndrome that affects cognitive, behavioral, and social development. Nonliteral language (NLL) comprehension has not been examined in children with NF1. This study examined NLL comprehension in children with NF1 and associated neuropsychological correlates. Method: NLL comprehension was examined in children with NF1 (n = 49) and typically developing (TD) controls (n = 27) aged 4–12 years using a novel NLL task. The task assessed comprehension of sarcasm, metaphor, simile, and literal language. Cognitive (Wechsler Scales Composites or the Woodcock–Johnson Test of Cognitive Abilities Revised scaled scores) and behavioral (attention deficit hyperactivity disorder [ADHD] symptoms) correlates of NLL comprehension in children with NF1 were also examined. Results: Children with NF1 demonstrated significantly poorer sarcasm comprehension than TD children and a vulnerability in metaphor comprehension. Simile and literal language comprehension were not significantly different between groups. Working memory difficulties and impulsive/hyperactive ADHD symptoms were associated with a reduced ability to identify sarcasm in NF1, while verbal comprehension, fluid reasoning, and inattentive ADHD symptoms were not. Conclusions: Results suggest children with NF1 experience challenges in understanding complex NLL comprehension, which are related to reduced working memory and increased impulsivity/hyperactivity. This study provides an initial insight into the figurative language abilities of children with NF1, which should be examined in relation to their social difficulties in future studies.