The integration and disintegration of newly learned meaningful words through retrieval-induced forgetting.

Little is known about how discrete elements of newly learned words, such as written form and multiple aspects of meaning, become integrated with each other and whether the elements break apart across forgetting. Taking inspiration from research into multi-element event memories (e.g., Horner & Burgess, 2013), we examined whether there is an association between retrieval successes of different elements of the same new word (i.e., retrieval dependency) and whether this statistical association remains one week later after some words are forgotten. Across five pre-registered experiments, participants encoded new words made from an orthographic word form (e.g., flimir) presented alongside pictorial (e.g., picture of a balloon) and auditory (e.g., sound of a baby crying) elements representing word meaning inferred from context. Retrieval dependency was present immediately after learning showing that the discrete elements become rapidly bound together. The manner in which they are forgotten however was subject to retrieval-induced forgetting (RIF). The word elements remained bound together one week later when no immediate retrieval test occurred after learning. However, when half of the words were tested post-learning, the non-tested half later fragmented (i.e., no dependency observed at delayed test). This fragmentation was prevented when learning of non-tested words occurred after retrieval of tested words. We suggest that RIF may extend to the nature of forgetting for new words, and call for an update of word learning theories which account for forgetting.