Child Psychology 560 Language Development 2 03 04 2014 How many words do you know 40 000 60 000 average for college students How many words did you know when you were born 0 Word learning Roadmap 1 Map words onto the world 2 Generalize to novel situations Use grammatical cues How do young children learn word meanings 1 Map words onto the world The gavagai problem Quine 1960 o o o When an informant points at something and say gavagai if you don t know the meaning of the world you can attribute a lot of guesses noun adjective demand Each word has infinite possible meanings How do kids find right meaning Gavagai rabbit Constraints on word meanings o Markman We choose some meanings over others Whole object constraint Words refer to whole objects Ex fish does not mean a part color or texture Problem Also need to label parts of objects Additional constraint mutual exclusivity o Mutual Exclusivity New word fin If know fish fin must mean a part or color What about bilinguals Byers Heinlein Werker 2009 o o Each object has only one label used to make guesses on what a word means by process of elimination M E in babies learning multiple languages Results Monolinguals M E 17 18 mo Bilinguals marginal M E use Trilinguals no M E use Fast Mapping o o Map novel word to novel item after a single trial Carey Bartlett 1978 Fast mapping 2 years old Label new color once with novel word o chromium Remembered a week later Fast mapping in dogs Mutual exclusivity figured out the toy Darwin because it was the one toy he didn t know the name for Cross Situational Statistics o o o Keep track of words across different situations Alternative way to map words to world Example you hear ball and bat but don t know which one is which when presented with ball and dog later you can infer which one is the ball o Results 12 14 months learned the world can keep track of cross situational statistics across time Pragmatic Cues o Child was paying attention to where the adult was looking to figure out what the ziggy was o Took advantage of the cues given to us Adult s emotional reaction helped to solve the gavagai problem 2 Generalize to new situations Meaning errors o Overextension word too broad o Underextension word too specific E g doggie all 4 legged creature E g doggie Milo Shape Bias o o o o Using shape to generalize Taught a novel word Tested on novel exemplars of the object 2 and 3 year olds Extended different sized and texture Did not extend different shape Shape bias increased with age Can be trained 3 Grammatical Cues Grammar o o Morphology Combing morphemes smallest unit of meaning Walk walked walking walks Help helped helping helps Syntax Combining words Brown 1957 o 3 year old Heard the word sib tested on how they interpreted it dog bites man vs man bites dog Kids heard either sibbing a sib some sib sibbing referred to action sib thought it was the container some sib confetti like substances How do kids learn verbs o o Map from world to word Problems Hear verb without action Many verbs fir any action Syntactic Bootstrapping o Use syntax to determine verb meaning o Ex I blicked John the ball I blicked John I blicked Naigles 1990 chase vs flee 2 year old heard either The duck is gorping the bunny The duck and the bunny are gorping Look longer at matching video Morphology o o Morphemes smallest units of meaning Rules E g Add ed for past tense o Lots of exceptions o Regular forms Irregulars went came saw was ate Berko 1958 The wug test Can kids apply morphology rules to new words Early awareness and use of morphology Can t be due to imitation Parents don t correct grammar even when they do it doesn t work They correct truth value Pre emption o Expect regular form but hear irregular form Correction o o Preschoolers pass We went swimming yesterday Individual differences Word recognition o o o What leads to individual differences SES Hart and Risley 1994 Welfare 616 words hour Working class 1251 words hour Professional family 2153 words hour Affects speed of word recognition 03 04 2014 03 04 2014