The magic of matching – speech production and perception in language acquisition

This thesis investigates the relationship between speech production and speech perception in the early stages of phonological and lexical acquisition. Previous studies have mainly focused on independent investigations of speech production and perception abilities in language acquisition. This thesis connects the individual speech production capacities to the child's perception and is organized around three major studies: Study I explores methodological alternatives such as the combination of EEG and eye-tracking in different Swedish participant groups: adults, 17-month-olds, and 24-month-olds. Visual and auditory stimuli, as well as the connection between word production and word perception are explored. Study II investigates phonological capacities in terms of consonant inventory, percentage of correctly pronounced words, segmental errors, as well as phonological templates in relation to vocabulary size in a group of Swedish 18-month-olds. Study III studies the influence of the children's individual phonological and lexical capacities in speech production on their word recognition in a group of Swedish toddlers with a productive vocabulary size above 100 words. The general results show that children accept mispronounced word forms as appropriate word candidates when the word forms are related to their individual word production. The occurrence of segmental errors increases with vocabulary size, and phonological templates are more likely to be observed in children with a productive vocabulary size above 100 words. The results thus indicate an influence of the individual child's production on word recognition, and a relationship between phonological capacities and lexical knowledge. These insights contribute to theoretical debates in linguistics regarding the abstractness of phonological word form representations and reveal a closer relationship between production and perceptual abilities in toddlers than what has previously been shown