The vocabulary spurt predicts the emergence of backward semantic inhibition in 18‐month‐old toddlers

Abstract

The current study examines the relationship between 18‐month‐old toddlers’ vocabulary size and their ability to inhibit attention to no‐longer relevant information using the backward semantic inhibition paradigm. When adults switch attention from one semantic category to another, the former and no‐longer‐relevant semantic category becomes inhibited, and subsequent attention to an item that belongs to the inhibited semantic category is impaired. Here we demonstrate that 18‐month‐olds can inhibit attention to no‐longer relevant semantic categories, but only if they have a relatively large vocabulary. These findings suggest that an increased number of items (word knowledge) in the toddler lexical‐semantic system during the “vocabulary spurt” at 18‐months may be an important driving force behind the emergence of a semantic inhibitory mechanism. Possessing more words in the mental lexicon likely results in the formation of inhibitory links between words, which allow toddlers to select and deselect words and concepts more efficiently. Our findings highlight the role of vocabulary growth in the development of inhibitory processes in the emerging lexical‐semantic system.

Parental Reports of Preschoolers' Lexical and Syntactic Development: Validation of the CDI-III for European Portuguese

“…The period after children's second year of life is usually associated with accelerated language development, both in terms of lexical knowledge and syntactic development. The vocabulary spurt-a rapid acceleration in the acquisition of new words-usually occurs around 18-24 months (Kauschke and Hofmeister, 2002;Chow et al, 2019). This phenomenon may be related to cognitive development and the resulting expansion of conceptual and categorization skills that occur at this stage (Pérez-Pereira, 2004).…”

Developmental changes in phonological and semantic priming effects in Spanish-speaking toddlers.

“…Vocabulary size-the number of words a toddler knows-is a factor that contributes to the early development of semantic and phonological organization. Rämä et al (2013) found that toddlers at 18 months of age with larger vocabularies showed different eventrelated potentials between semantically related and unrelated pairs of words (for similar results, see Chow et al, 2019), while those with smaller vocabularies did not. In recent longitudinal work with German toddlers, Avila-Varela et al (2021) observe that phonological priming effects were predicted by participants' current vocabulary size, even after controlling for their age.…”

“…Previous studies have interpreted a greater PTL to the related than the unrelated target as facilitation in target identification and the opposite pattern as interference (Angulo-Chavira & Arias-Trejo, 2018Arias-Trejo & Plunkett, 2013;Chow et al, 2016Chow et al, , 2019Mani & Plunkett, 2010. Our time-course results could be interpreted this way, because they present consistent behaviors with respect to the mean PTL.…”

Lexico-semantic structure in vocabulary and its links to lexical processing in toddlerhood and language outcomes at age three.

“…This semantic facilitation “boost” in lexical processing may be attributable to a variety of factors, including more efficient and robust activation of target word meanings, coupled with appropriate inhibition of nontarget meanings as the neighborhoods surrounding a word increase in density. For example, Chow and colleagues (2019) posit that the rapid increase in vocabulary around the time of the vocabulary spurt may be driven by (or result in) the need to develop inhibitory lexical activation mechanisms that prevent massive overactivation and interference in denser lexical neighborhoods that accompany vocabulary growth.…”