Morpheme Segmentation in School-aged Children

One of the major questions in the cognitive science of language is how children learn the productive systems that encompass the grammar of our native languages. This paper addresses how children learn morphology, the systematic relationship between form and meaning. For example, the English plural can be made in one of many ways, most commonly with the addition of the suffix /-s/. While such patterns between sound and meaning are subject to exceptions, marking meanings through regular forms is one of many ways in which language is a productive, combinatorial system. There are at least two possible ways in which morphology could be learned. One possibility is that the learner acquires relationships between forms and their meanings by grouping words that share a common component of meaning and then determining what part of the form is used to signal this meaning. For example, to acquire the English plural, the learner would take known plural words in the lexicon (dogs, cats, bugs, buses) and extract the commonality that the majority of these words end in the letter ‘s’ to form the rule that ‘s’ marks plural. The other possibility is that the learner works in the opposite direction, observing that a number of words in the lexicon have commonalities of form and inferring a morphological or semantic relationship among words that sound similar. Discovering the regularities among forms, the learner can also determine the system that relates form to meaning. For example, the words dogs, cats, bugs, buses all end in ‘s’, and are therefore likely to be related in meaning. These routes to discovering morphological regularities have different advantages and disadvantages. Using semantic relations to discover regularities in form requires knowing the meanings of the words, so the learner would have to master several sets of word meanings before acquiring their morphological