Browsing by Author "Saarelainen, Taru"

Word segmentation from continuous speech is an important step in the early development of speech and language. Even though there has been some research in this area, the exact mechanisms of word segmentation are not yet known. Most of the research has been conducted using behavioural methods that are based on the shifting of the infant’s attention, but these methods do not permit one to study the earliest steps of infant development. Recent advances in brain research methods have allowed the investigation of word segmentation in new-born babies, and new information shows that the basis for word segmentation is evident very early on in development, even from birth. The goal of this thesis is to review the recent findings on word segmentation abilities of infants under the age of one year. A literary search was conducted in the PubMed database using the search terms "word segmentation development infants". The articles chosen for this thesis were mostly experimental research articles on word segmentation skills, with the subjects being infants under the age of one year. Newer articles were preferred, and some additional articles were chosen from the references of already chosen articles. Based on the recent brain imaging experiments, even new-born infants can segment words from continuous speech. At least prosody and the transitional probabilities of syllables are word segmentation cues that are available to the new-born. Segmenting words from the edges of utterances seems to be easier than segmenting utterance medial words. Infant directed speech includes multiple amplified word segmentation cues in comparison to adult directed speech, and it seems to facilitate earlier word segmentation. The amount of speech an infant hears very early on might affect later word segmentation abilities. When social learning is possible, infants might segment words easier in social contexts, at least when compared to learning through videos. Word segmentation seems to utilize the same brain regions as phonological short-term memory and thus the development of phonological short-term memory might be connected to the development of word segmentation abilities.