  Speech directed to children differs from adult-directed speech in linguistic
aspects such as repetition, word choice, and sentence length, as well as in
aspects of the speech signal itself, such as prosodic and phonemic variation.
Human language acquisition research indicates that child-directed speech helps
language learners. This study explores the effect of child-directed speech when
learning to extract semantic information from speech directly. We compare the
task performance of models trained on adult-directed speech (ADS) and
child-directed speech (CDS). We find indications that CDS helps in the initial
stages of learning, but eventually, models trained on ADS reach comparable task
performance, and generalize better. The results suggest that this is at least
partially due to linguistic rather than acoustic properties of the two
registers, as we see the same pattern when looking at models trained on
acoustically comparable synthetic speech.
