PSYCH 2410 1st EditionLecture 11Outline of Language Development Part 1I. Theories of Language DevelopmentII. Infant-Directed SpeechIII. Sound CategorizationOutline of Language Development Part 2I. Producing Speech SoundsII. First WordsIII. Beyond First WordsLanguage Development of Part 2I. Producing Speech Sounds- First Speech Sounds: What do babies say?o 0-2 mos=Reflexive vocalization  crying, hiccups, burps, sighs (responses to environment)o Not speech-likeo Communication is not linguistic or intentional- Around 2 mos: cooing begins (not linguistic or intentional)- Next: Babbling (not real words or meaning)1) Early Babbling (4-6 mos)- Occasional real syllables, vocal play, deaf infants too2) Canonical Babbling (7-8)- Sounds like real syllables (reduplicated and variegated later)3) Jargon Babbling (end of 1st year)- Research with deaf infantso Canonical babbling occurs late (11-25 mos)o Less frequent, fewer syllableso Study: do infants exposed to sign language babble with their hands? Method: deaf and hearing infants videotaped at 10, 12, and 14 mos Results: all infants produced meaningful gestures (“up”, “give me”); all infants produced manual babbling (possible syllables of signed language)o Need and ability to communicate is innate- Summary:o Why do babies babble?  Trying out equipment Picking up the forms of a language observed Continues with first words and first signsII. First Words- The One-Word Stageo 12-14 mos learn and speak one word at a time, new words appear slowlyo Content words: word applied to an object (ball, cookie)o Not function words (although, or, but, the)o 51% = category names for things action, social, routines, modifiers some cultural variability o Error at One Word Stage Overextension: use one word to refer to other different things with different actual names Fast mapping: quickly connect new word with underlying concept- Method: new object new word- Results: consistently chose the correct object at above-chance levelIII. Beyond First Words- The Two-Word Stage: (18-30 mos), begin combining words into 2-word sentences- Telegraphic speech: content words remain, function words still left out, word order correct early- Comprehension of word order studyo Method: 16-18 mos, hear sentenceo Results: looked longer at matching video; 1-word speakers know something about English word ordero Method: 21 mos, use made up verb o Results: by about 2 years children figure out that pre-verbal noun is the actor- After two-word stage: gradual increase in length of sentences; function words are addedo Picture pointing comprehension task Method: 4 different conditions (grammatically correct, ungrammatical, missing word, nonsense) Results: picked more accurately if heard the correct function word - Comprehension precedes productiono Even one-word speakers- Over-regularization: incorrect grammatically verbs (gogoed)- There is a critical period in language