Semantic support and sex differences in toddlers' spoken word recognition

Research shows that as toddlers' vocabularies expand, words in the early lexicon become increasingly interconnected through shared phonological and semantic features. Understanding how these dimensions jointly shape lexical organization is central to theories of early spoken word recognition. The present study investigated how the simultaneous presence of phonological and semantic similarity between nouns influences lexical activation during spoken word recognition. We presented 21-month-old English monolinguals with an intermodal preferential looking task adapted to a priming paradigm while their eye movements were recorded with an eye-tracker. Participants heard a spoken noun (prime) followed by a related or unrelated spoken noun (target). The experiment included three conditions: Phonologically Related, where prime-target pairs share the initial phonemes (e.g., toe-toast); Phono-Semantically Related, where prime-target pairs share the initial phonemes and belong to the same semantic category (e.g., turkey-turtle); and Unrelated, where prime-target pairs do not share the initial phonemes and do not belong to the same semantic category (e.g., bubble-toast and box-turtle). Results revealed two key findings: (1) Targets in the Phonologically Related condition elicited significantly fewer looks than the Unrelated condition, suggesting phonological interference. (2) Targets in the Phono-Semantically Related condition elicited significantly more looks than both the Unrelated and Phonologically Related conditions, indicating strong facilitation when both cues are present. Additionally, girls demonstrated more pronounced word recognition than boys. This study extends our understanding of the interactive roles of phonological and semantic cues, as well as sex differences, in mental lexical organization among young toddlers.