Vocabulary Development

A team transcribed 990 minutes of speech from 33 teachers and found that what predicted children’s vocabulary growth was not which words they used but how they joined their clauses — and that teachers simplified their syntax precisely when introducing sophisticated words.

A Dutch longitudinal study of 49 mother-child pairs found that how a mother stretched her pitch range when introducing an unfamiliar word at 18 months predicted vocabulary growth to 24 months with striking strength — while the same prosodic exaggeration on familiar words predicted nothing at all.