4.1. Language acquisition in childhood

Week 4 Part 1 will help you to:

• become familiar with key concepts in language development such as ‘the critical period’ and ‘parentese’
• gain an understanding of the stages of language acquisition and the crucial role of the home and school environments in supporting this process

To reach these goals, you are expected to do the following:

• read the introduction below
• watch the videos that have been uploaded
• check your knowledge and understanding with an activity at the end of each task

Please note: the total work time required to complete 4_1 is about 75 minutes.

 Reading

The acquisition of language is one of the most remarkable achievements of early childhood. By age 5, children essentially master the sound system and grammar of their first language (L1) and acquire a vocabulary of thousands of words. But how does the language acquisition process unfold and when do children reach various milestones?

3 dimensions of language acquisition process:

Phonological development (the sound system of language)

Newborn babies have the ability to hear and discriminate speech sounds. During the first year, they become better at hearing the contrasts in their first language (L1) and become insensitive to acoustic differences that are not relevant to this language. This tuning of speech perception to the ambient language is the result of a learning process in which infants form mental speech sound categories around clusters of frequently occurring acoustic signals. These categories then guide perception such that variation within a category is ignored but variation between categories is attended to through focused listening.

• The first sounds infants produce are involuntary cries and noises that are not speech-like. In their vocal development they then begin to produce canonical syllables (well-formed consonant + vowel combinations), which appear between 6 and 10 months, followed shortly by reduplicated babbling (repetitions of syllables).
• When first words appear, they make use of the same sounds, and they contain the same numbers of sounds and syllables, as the preceding babbling sequences. One process that contributes to early phonological development appears to be infants’ active efforts to reproduce the sounds they hear. In babbling, infants may be discovering the correspondence between what they do with their vocal apparatus and the sounds that come out.
• At approximately 18 months, children appear to have achieved a mental system for representing the sounds of their language and producing them within the constraints of their abilities. At this point children’s production of speech sounds becomes consistent across different words.
• Studies show that children exposed to second languages (L2) in infancy through rich language input in a socially interactive context acquire the L2 following the same pattern as the L1: first by absorbing the sounds then gradually reproducing them through repeated syllables, then words, then chunks. Their ability to discriminate phonemic patterns in early infancy make babies ideal foreign language learners.

Lexical development (learning words)

Infants understand their first word as young as 5 months, produce their first words generally between 10 and 15 months of age, reach the 50-word milestone in productive vocabularies around 18 months of age, and the 100-word milestone between 20 and 21 months. After that, vocabulary development proceeds so rapidly that it becomes difficult to track lexical development. The vocabulary size of an average 6-year-old has been estimated at 14,000 words.

The task of word learning has multiple components and recruits multiple mechanisms.

• Infants make use of statistical learning procedures, tracking the probability that sounds appear together, and thereby segmenting the continuous stream of speech into separate words.
• The capacity to store those speech sound sequences, known as phonological memory, comes into play as entries in the mental lexicon are created.
• In the task of mapping a newly-encountered word onto its intended referent, children are guided by their abilities to make use of socially-based inferencing mechanisms (i.e., speakers are likely to be talking about the things they are looking at),by their cognitive understandings of the world (some word learning involved mapping new words onto pre-existing concepts), and by their prior linguistic knowledge (i.e., the structure of the sentence in which a new word appears provides clues to word meaning).
• Full mastery of the meanings of words may require new conceptual developments as well.

Morpho-syntactic development (from words to phrases)

Children begin to put two, then three and more words together into short sentences at approximately 24 months of age.

• Children’s first sentences are combinations of content words and are often missing grammatical morphemes or function words (e.g., articles and prepositions) and word endings (e.g., plural and tense markers).
• As children gradually master the grammar of their language, they become able to produce increasingly long and grammatically complete utterances. The development of complex (i.e., multi-clause) sentences usually begins some time before the child’s second birthday and is largely complete by age 4. In general, comprehension precedes production.

Sources:

Lightbown, P. and N. Spada. How Languages are Learned. Oxford UP: 2013 (4th edition).

Lust, B. Child Language: Acquisition and Growth. Cambridge UP: 2006.

Lust, B. and C. Foley. First Language Acquisition: The Essential Readings. Wiley & Sons: 2003.

Pinter, A. Children Learning Second Languages. Palgrave-MacMillan: 2011.

---

 Activity

First task: [45 min]

1. Watch the first video, “The Linguistic Genius of Babies” with Dr. Patricia Kuhl. A transcript of the talk is available at the link to support your viewing.

[[[https://embed.ted.com/talks/patricia_kuhl_the_linguistic_genius_of_babies height=400]]]

2. Answer the questions below to check your comprehension.

Second task [30 min]

1. Now watch two short videos on ‘parentese’.

Video 1: Mothers speaking ‘motherese’ /’parentese’ in English and Japanese. Note how they change their pitch, tone and rate of speech.

Click on the link below (it is the same video previously watched) and forward to the segment from 04:00 to 04:57.

https://www.ted.com/talks/patricia_kuhl_the_linguistic_genius_of_babies/transcript

Video 2: A mother and 2-year-old child interacting at the lake. Note when and how the new word ‘quacking’ emerges for the child. Click on the link below.

Video_2_-_mother_child_interaction.mp4

2. Read the attached article “Phonemic learning and ‘parentese'” by Claudia Civinini at this link:

http://www.elgazette.com/item/447-could-native-speakers-and-parentese-be-key-to-infant-foreign-language.html

3. Answer the questions on the attached worksheet to check your comprehension of the concepts.

---