Children with typical development or Down syndrome benefit from testing versus restudy of arbitrary event sequences across long-term delays and in the face of sleep disturbance.

Improved memory after prompted retrieval, also known as the testing effect, is evidenced in adults to support long term memory, but rarely examined in children in pre-school or with intellectual disabilities, such as Down syndrome (DS). This study examined episodic memory across one-month, manipulating the presentation of episodic information to compare testing versus restudy of arbitrary event sequences, and the effect of sleep variables. Retrieval rates were compared at 5-minute and one-month delays in 52 children with DS (aged 6-18, 27 male, 24 White) compared to 59 children with typical development (aged 3-7, 23 male, 35 White). A single test improved recall in the DS group over long term delays, this is a novel finding and relevant to real-life and classroom experiences.