Neuropsychological Functioning in Individuals with Noonan Syndrome: a Systematic Literature Review with Educational and Treatment Recommendations

Noonan syndrome (NS) is a relatively common genetic syndrome with variable features including short stature, congenital heart disease, distinctive facial characteristics, skeletal anomalies, and varying degrees of developmental delay. NS is caused by gene mutations in a cellular signaling pathway that is essential for typical growth and development. Research in the past few decades has revealed that individuals with NS have highly variable neurocognitive and behavioral outcomes. To a certain extent, variability in cognitive functioning depends on the particular gene where a mutation is found; additionally, factors related to medical severity and environmental effects contribute substantially to outcomes. This article contains a systematic review of research on neuropsychological features of NS, including cognition, motor development, language, memory, attention, visual perception, adaptive behavior, social skills, and mental health concerns. Given the wide variety of possible cognitive and behavioral complications associated with NS, it is recommended that clinical neuropsychological evaluation of cognitive, adaptive, and psychological domains of functioning should be standard of care for all individuals with NS. Suggested considerations for assessment of individuals with NS are provided. The paper concludes with recommendations for educational and therapeutic interventions, as well as suggestions for future research directions.