Prolonged development of forced-choice recognition when targets are paired with non-corresponding lures

Abstract

Previous research suggests that mnemonic discrimination (i.e., the ability to discriminate between previously encountered and novel stimuli even when they are highly similar) improves substantially during childhood. To further understand the development of mnemonic discrimination during childhood, the present study had 4-year-old children, 6-year-old children, and young adults complete the forced-choice Mnemonic Similarity Task (MST). The forced-choice MST offers a significant advantage in the context of developmental research because it is not sensitive to age-related differences in response criteria and includes three test formats that are theorized to be supported by different cognitive processes. A target (i.e., a previously encountered item) is either paired with a novel item (A-X), a corresponding lure (A-A′; i.e., an item mnemonically similar to the target), or a non-corresponding lure ( A-B′; i.e., items mnemonically similar to a different previously encoded item). We observed that 4-year-old children performed more poorly than 6-year-old children on the A-X and A-A′ test formats whereas both 4- and 6-year-old children performed more poorly than young adults on the A-B′ test format. The MINERVA 2.2 computational model effectively accounted for these age-related differences. The model suggested that 4-year-old children have a lower learning rate (i.e,. probability of encoding stimulus features) than 6-year-old children and young adults and that both 4- and 6-year-old children have greater encoding variability than young adults. These findings provide new insight into possible mechanisms underlying memory development during childhood and suggest that different processes contribute to developmental improvements during childhood and declines during aging.