The Effect of Prior Learning on Word Learning

The goal of this clinical trial is to compare two treatment conditions for late talking toddlers. In 8 weeks of word learning treatment, toddlers will be taught words that sound more like the words they already know or sound less like the words they already know. The investigators see which group learns more, to understand if choosing words that let children use the knowledge they already have helps with learning.

Late talking toddlers will be assigned to be in the More Familiar Sounds condition or the Less Familiar Sounds condition. Both groups will receive 8 weeks of Vocabulary Acquisition and Usage for Late Talkers (VAULT) word learning treatment (2x/week for 30 minutes per session) using their words. The investigators will compare learning within children (taught words v. control words that are not explicitly taught) to make sure the learning that is happening is due to the treatment and not just maturation. The investigators will compare across groups to see if the group treated with More Familiar Sounding words learns more than the group treated with Less Familiar Sounding words.