book excerptise:   a book unexamined is not worth having

Child language: acquisition and growth

Barbara Lust

Lust, Barbara;

Child language: acquisition and growth

Cambridge University Press, 2006, 389 pages

ISBN 0521444780, 9780521444781

topics: |  language-acquisition

Appendix 1 Developmental milestones in motor and language development

	(adapted from Lenneberg 1967, 128–130)
		Motor Development 		Vocalization and Language

Year 1

0–6 mo
3 mo 	Supports head when prone 	Less crying than at 8 weeks;
  			      	   		smiles when talked to; cooing

4 mo 	Plays with rattle; head		Responds to human sounds more
 	self-supported	   		definitely


5 mo 	Sits with props	 		Cooing begins to be interspersed with
					more consonantal sounds; all
					vocalizations are very different from
					the sounds of the mature language of
					the environment

6–12 mo

6 mo 	Sitting; bends forward and	Cooing changing into babbling
  	uses hands for support;		resembling monosyllabic utterances;
	cannot yet stand without	neither vowels nor consonants have very
	help; no thumb apposition	fixed recurrences

8 mo 	Stands holding on; grasps	Reduplication frequent; intonation
  	with thumb apposition		patterns distinct; utterances can
					signal emphasis and emotions

10 mo	Takes side steps, holding	Vocalizations are mixed with sound-play
   	on; pulls to standing		such as gurgling or bubble-blowing; tries
	position			unsuccessfully to imitate sounds

12 mo	Walks when held by hand;	Identical sound sequences replicated
	walks on feet and hands,	with higher relative frequency of
	knees in air; seats self on	occurrence and words are emerging;
	floor				definite signs of understanding some
					words and simple commands

Year 2: 18–24 mo


18 mo	Grasp, prehension, and		Has a repertoire of three to fifty
	release fully developed;	words; babbling now of several
	gait stiff, propulsive, and	syllables with intricate intonation
	precipitated; creeps		pattern; little ability to join any of
	downstairs backwards		the lexical items into spontaneous
					two-item phrases; understanding is
					progressing rapidly

24 mo	Runs, but falls in sudden	Vocabulary of more than fifty items;
   	turns; can quickly alternate	begins to join items into two-word
	between sitting and stance;	phrases; all phrases appear to be own
	walks stairs up or down,	creations; increase in communicative
	one foot forward only		behavior and interest in language

30 mo	Jumps into air with both	Fastest increase in vocabulary; no
	feet; stands on one foot for	babbling; utterances have communicative
	about two seconds; takes	intent; frustrated if not understood by
	few steps on tiptoe; can	adults; sentences and phrases have
	move digits independently;	characteristic child grammar;
	manipulation of objects		intelligibility not very good;
	much improved			understands what is said


Year 3  Tiptoes well; runs smoothly	Vocabulary of some 1,000 words; about
	with acceleration 		80 percent of utterances are
					intelligible even to strangers;
					grammatical complexity of utterances is
					roughly that of colloquial adult
					language

Beyond 3 Jumps over rope; hops on	Language is well-established;
	dominant foot; catches ball	deviations from adult norm tend to be
	in arms; walks line		more in style than in grammar

Appendix 2a Developmental milestones in infant speech perception


Year 1
0–2 mo  Distinguishes maternal voice, speech and non-speech
	  Evidences Categorical Perception 
	  Perceives wide set of sound distinctions corresponding to possible phonetic
		  contrasts along many major dimensions of phonetic variation
	  Discriminates between different numbers of syllables 
	  Discriminates canonical and non-canonical syllables 
	  Discriminates certain prosodic differences in stress and accent 

2–3 mo  Discriminates certain allophonic variations between sounds, e.g., the
	  	allophones of [t] and [r] in “night rate” vs. “nitrate” 
	  Distinguishes bisyllables with initial stress from those with final
	  	stress, e.g., “´bada” from “ba´da”
	  Compensates for changes in speaking rates 

4 mo	Prefers to listen to words over other sounds 
	  “Duplex Perception” is evident 

5 mo	Capable of linking auditory and articulatory information (Kuhl and Meltzoff
		  1982, 1984)

6–7 mo	Pair of syllables recognized as unit when “supported by rhythmic familiarity”
		  regardless of syllable ordering (Morgan and Saffran 1995)
	  When acquiring English, distinguishes English words compared to
	  	Norwegian words, but not compared to Dutch (Jusczyk, Friederici
	  	et al.  1993); infant appears to know some aspects of possible
	  	patterns of words in specific language
	  First evidence that early perception of sound distinctions is being
	  	narrowed to more closely reflect the Specific Language Grammar
	  	being acquired; certain distinctions weaken or disappear when
	  	not in the specific language being acquired (Werker and Lalonde
	  	1988; Polka and Werker 1994)
	  “Magnet Effect”: recognition of specific language “prototype” vowel
	  	sounds (Kuhl et al. 1992)
	  Word segmentation skills apparent: infant recognizes words in
	  	sentences which were heard in isolation (monosyllabic words
	  	like “dog” or bisyllabic words like “doctor”) and recognizes
	  	words in isolation which were heard in sentences 
	  Recognizes recurrence of a three-sound sequence of continuous
	  	     synthesized speech (Saffran, Aslin and Newport 1996)

8 mo	Recognizes words from stories read two weeks earlier (Jusczyk and Hohne
	  	1997)
	  Recognizes phonotactic patterns of specific language, e.g.,
	  	strong–weak patterns in English, and listens longer to these

9 mo 	Distinguishes English from Dutch words (Jusczyk, Luce and Luce 1994)
	Uses phonotactic information to segment speech into words (Mattys and
	  Jusczyk 2001)
	  Prefers language-specific phonotactically well-formed strings
	  Integration of segmental and suprasegmental information in
	  	recognition of units 
	  Distinguishes passages with pauses between words from those with
	  	pauses within words 
	  Integrates multiple sources of information to locate word boundaries
	  	in fluent speech, phonotactic and prosodic 

10–11 mo  Uses context-sensitive allophones in segmenting words
	  Loses response to distinctions of some allophonic sound variations

12 mo Retains discrimination of phonetic contrasts which are phonemic in the
	  	infant’s native Specific Language Grammar; but has ceased to
	  	demonstrate discrimination of many, if not most, others 
	  Onset of first words in production (appendix 3)
Year 2

14 mo Does not use phonetic detail in a task requiring the pairing of words
	  	and objects, suggesting “functional reorganization” (e.g.,
	  	/bih/ vs. /dih/) 


amitabha mukerjee (mukerjee [at-symbol] gmail.com) 2011 Feb 20