A new preprint By Rachael Hulme, Anisha Begum, Kate Nation and Jenni Rodd looks at how contextual diversity affects early stages of word learning.
Diversity of narrative context disrupts the early stage of learning the meanings of novel words

There’s an important distinction between ‘situational diversity’ (i.e. the context in which words occur) and ‘heterogeneity’ (i.e. polysemy/diversity in words’ meanings). These typically co-occur in natural language, so we wanted to tease contextual diversity apart from polysemy.
Adults learned new words and their meanings by reading paragraphs with either five different narrative contexts or a single coherent narrative context. We controlled the semantic features of word meanings across conditions to avoid influences from polysemy.
Diversity of narrative context did not affect word-form learning but disrupted learning of word meanings – more semantic features were correctly recalled for words learned in a single coherent narrative context.
So in the early stages of learning meanings of new words, learning is boosted by anchoring them to a single coherent narrative discourse. The temporary representations that are built to support discourse comprehension may play an important role in supporting word learning.
The expt was preregistered, and materials, data & analysis code are available via OSF: https://osf.io/2bnw3
Here’s a poster summary of this research: https://bit.ly/3qZ7BSo