Preschoolers with Down syndrome do not yet show the learning and memory impairments seen in adults with Down syndrome

• Published in: Developmental science Vol. 18; no. 3; pp. 404 - 419
• Main Authors: Roberts, Lynette V., Richmond, Jenny L.
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01.05.2015; Wiley-Blackwell; Wiley Subscription Services, Inc
• Subjects: Adults; Age Differences; Age Factors; Analysis of Variance; Association Learning; Attention; Brain Hemisphere Functions; Case-Control Studies; Child, Preschool; Cognition - physiology; Control Groups; Down Syndrome; Down Syndrome - complications; Early Intervention; Executive Function; Eye Movements; Female; Genetics; Humans; Learning Disabilities; Learning Disorders - diagnosis; Learning Disorders - etiology; Male; Measures (Individuals); Memory; Memory Disorders - diagnosis; Memory Disorders - etiology; Nonverbal Ability; Preschool Children; Reaction Time; Receptive Language; Retention (Psychology); Scores; Time Factors
• ISSN: 1363-755X; 1467-7687
• DOI: 10.1111/desc.12225

Individuals with Down syndrome (DS) exhibit a behavioral phenotype of specific strengths and weaknesses, in addition to a generalized cognitive delay. In particular, adults with DS exhibit specific deficits in learning and memory processes that depend on the hippocampus, and there is some suggestion of impairments on executive function tasks that depend on the prefrontal cortex. While these functions have been investigated in adults with DS, it is largely unclear how these processes develop in young children with DS. Here we tested preschoolers with DS and typically developing children, age‐matched on either receptive language or non‐verbal scores as a proxy for mental age (MA), on a battery of eye‐tracking and behavioral measures that have been shown to depend on the hippocampus or the prefrontal cortex. Preschoolers with DS performed equivalently to MA‐matched controls, suggesting that the disability‐specific memory deficits documented in adults with DS, in addition to a cognitive delay, are not yet evident in preschoolers with DS, and likely emerge progressively with age. Our results reinforce the idea that early childhood may be a critical time frame for targeted early intervention. A video of this article can be viewed at https://www.youtube.com/watch?v=r6GUA6my22Q&list=UU3FIcom6UpITHZOIEa8Onnw Adults with Down syndrome (DS) exhibit specific deficits in learning and memory processes that depend on the hippocampus and prefrontal cortex, however it is largely unclear how these processes develop in young children with DS. We tested preschoolers with DS on these areas, and as shown in the figure, they performed equivalently to mental‐age matched controls. This finding suggests that the additional disability‐specific learning and memory deficits seen in adulthood, are not yet evident in pre‐schoolers with DS and likely emerge progressively with age.