Friday, November 04, 2005

Vocabulary (Gc-VL) development in children

An informative article summarized (abstract and select material from intro and discussion) below re: cognitive abilities related to vocabulary (Gc-VL) development in children.

McBrideChang, C., Wagner, R. K., Muse, A., Chow, B. W. Y., & Shu, H. (2005). The role of morphological awareness in children's vocabulary acquisition in English. Applied Psycholinguistics, 26(3), 415-435.

Abstract (NOTE - the blogmaster has excercised his CHC editorial prerogative and has inserted relevant CHC ability notation were appropriate
  • Tasks of speeded naming [Glr-NA), phonological awareness [Ga-PC], word identification (Grw-RD), nonsense word repetition (Grw-RD), and vocabulary (Gc-VL), along with two measures of morphological awareness (morphological structure awareness and morpheme identification), were administered to 115 kindergartners and 105 second graders. In the combined sample, 48% of the variance in vocabulary knowledge was predicted by the phonological processing and reading variables. Morphological structure awareness and morpheme identification together predicted an additional unique 10% of variance in vocabulary knowledge, for a total of 58% of the variance explained; both measures of morphological awareness were uniquely associated with vocabulary knowledge. Results underscore the potential importance of different facets of morphological awareness, as distinct from phonological processing skills, for understanding variability in early vocabulary acquisition.
Additional information from article
  • Our working definition of morphological awareness is awareness of and access to the meaning and structure of morphemes in relation to words. Morphemes are the smallest units of meaning in language. Carlisle (1995, p. 194) similarly defines morphological awareness as, “children’s conscious awareness of the morphemic structure of words and their ability to reflect on and manipulate that structure.” Our focus is on children’s abilities to distinguish and manipulate morphemes at the word level. This broad definition allows us, theoretically, to consider children’s knowledge of both derivations and inflections in language simultaneously. Derivational morphology includes knowledge of prefixes (e.g., the un in undisciplined or the pre in preoperational), suffixes (e.g., the ation in graduation or simulation), and compounding (e.g., cowboy and sunlight are both compound words). Inflectional morphology focuses primarily on indicating grammatical changes in words (e.g., the s in dogs or the ed in acted are both grammatical inflections).
  • Like phonological processing, morphological awareness is likely comprised of multiple dimensions.
  • We focused on two such dimensions that might ultimately be useful for understanding vocabulary growth because they can be assessed in very young children without using print.
  • Morpheme identification is the ability to distinguish different meanings across homophones. This skill is demonstrated when a child understands that the flower in flowerpot is represented by a plant with petals as opposed to a sack of white powder (flour).
  • A second aspect of morphological awareness, morphological structure awareness is the ability to create new meanings by making use of familiar morphemes. A child who understands that the famous concept of greater than one wug is represented by the word wugs, involving two morphemes, demonstrates morphological structure awareness skill.
  • Across both groups of children, the combined tasks of morphological awareness were good predictors of vocabulary knowledge, even once phonological processing, word reading skill, and age were statistically controlled. These results have two interesting implications for future research. First, morphological awareness is a cognitive construct separable from phonological processing and reading skills and important for vocabulary acquisition. Second, both morpheme identification and morphological structure awareness are potentially unique features of vocabulary development.