Memory Research (in relation to language development)

Mean length utterance (MLU), as opposed to chronological age, has been found to be a more reliable index for language development. MLU is defined as the average length of a child\u27s utterance in morphemes (smallest units of meaning). In 1962 Roger Brown and his associates began a study of the development of language in children. They began collecting samples of spontaneous speech on a regular schedule over a period of time from three normal children. The data collected from Adam, Eve, and Sarah on mean length utterance, illustrates the systematic increase of MLU. As they began the process of combining words, Brown explained that a child\u27s language development follows a series of stages which are defined by their MLU level. This and other data (i.e. Dale 1976 used MLU as an index for language development in which irregularities could be compared), show that MLU is the best indicator of a child\u27s language developmental level