title: Disentangling early language development: modeling lexical and grammatical acquisition using an extension of case-study methodology.
abstract: The early lexical and grammatical development of 1 male child is examined with growth curves and dynamic-systems modeling procedures. Lexical-development described a pattern of logistic growth (R2 = .98). Lexical and plural development shared the following characteristics: Plural growth began only after a threshold was reached in vocabulary size; lexical growth slowed as plural growth increased. As plural use reached full mastery, lexical growth began again to increase. It was hypothesized that a precursor model (P. van Geert, 1991) would fit these data. Subsequent testing indicated that the precursor model, modified to incorporate brief yet intensive plural growth, provided a suitable fit. The value of the modified precursor model for the explication of processes implicated in language development is discussed.
authors.affiliation: Department of Psychology, Emory University. bfrobi01@homer.louisville.edu
authors.forename: B F
authors.initials: BF
authors.lastname: Robinson
authors.forename: C B
authors.initials: CB
authors.lastname: Mervis
mesh_terms: D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007804:Language Development; D008037:Linguistics; D008297:Male; D008960:Models, Psychological; D012107:Research Design