A study of children born prematurely has found differences in a subtle but important aspect of memory: the ability to form and retrieve memories about context. The study examined 33 8-to 10-year olds using magnetic resonance imaging to measure the volume of the hippocampi. The results suggest that the maturational state of the hippocampus at the time of birth influences the maturation of certain memory functions even at 8- to 10-years old.