title: How words can and cannot be learned by observation.
abstract: Three experiments explored how words are learned from hearing them across contexts. Adults watched 40-s videotaped vignettes of parents uttering target words (in sentences) to their infants. Videos were muted except for a beep or nonsense word inserted where each "mystery word" was uttered. Participants were to identify the word. Exp. 1 demonstrated that most (90%) of these natural learning instances are quite uninformative, whereas a small minority (7%) are highly informative, as indexed by participants' identification accuracy. Preschoolers showed similar information sensitivity in a shorter experimental version. Two further experiments explored how cross-situational information helps, by manipulating the serial ordering of highly informative vignettes in five contexts. Response patterns revealed a learning procedure in which only a single meaning is hypothesized and retained across learning instances, unless disconfirmed. Neither alternative hypothesized meanings nor details of past learning situations were retained. These findings challenge current models of cross-situational learning which assert that multiple meaning hypotheses are stored and cross-tabulated via statistical procedures. Learners appear to use a one-trial "fast-mapping" procedure, even under conditions of referential uncertainty.
authors.affiliation: Department of Psychology and Institute for Research in Cognitive Science, University of Pennsylvania, Philadelphia, PA 19104, USA. medinatn@sas.upenn.edu
authors.forename: Tamara Nicol
authors.initials: TN
authors.lastname: Medina
authors.forename: Jesse
authors.initials: J
authors.lastname: Snedeker
authors.forename: John C
authors.initials: JC
authors.lastname: Trueswell
authors.forename: Lila R
authors.initials: LR
authors.lastname: Gleitman
mesh_terms: D001245:Association Learning; D002675:Child, Preschool; D006801:Humans; D007802:Language; D007858:Learning; D008037:Linguistics; D016015:Logistic Models; D008568:Memory; D015233:Models, Statistical; D019370:Observation; D015203:Reproducibility of Results; D013067:Speech Perception / Q000502:physiology; D014706:Verbal Learning / Q000502:physiology*; D014741:Video Recording; D014825:Vocabulary