The Language Puzzle
Dr Jean Quigley, School of Psychology, TCD
First years of life most important in
n At birth, baby's brain has 100 billion neurons - will double in
size in the first year.
n During her first years, she will grow trillions of brain-cell
connections, called neural synapses. By 2, has twice as
many as an adult.
n Amount of stimulation directly impacts amount of synapses
n The rule for brain wiring is "use it or lose it." Synapses not
"wired together" through stimulation are pruned & lost during
a child's school years.
Baby is born ready to learn:
n Sound perception develops first & fastest
n At 2.5 months, memory is well developed –
n keeping infants in familiar surroundings enhances memory
n At 3.5 months, separate mother’s & father’s voice
n 4 months recognize their own name; detect sight/sound
correlations (watch a film appropriate to sound track)
n Experience at 6 months can be remembered two years later if
placed back in similar environment
n Reasoning evident at 7 months
n Comprehension > expression at 9 months by factor of 100:1
n 9 months baby will imitate simple actions
n 12 months can remember words for 24 hours
Sequence of language development
Vegetative sounds 0-6 weeks
Cooing 6 weeks
Laughter 16 weeks
Vocal play 16 weeks – 6 months
Babbling 6-10 months
Single word utterances 10-18 months
Two-word utterances 18 months
Telegraphic speech 2 years
Full sentences 2;6
Cracking the speech code
n Structuring sounds into segments (phonemes) which are
sequenced into fixed combinations (words).
n Treating these sequences as symbols for concepts
(meanings) that can be used in many different situations.
n Organizing sequences of words into phrases and
sentences (syntactic structures)
How do babies do this?
Not the whole story…
n Unexpected computational strategies & abilities used
by infant to acquire language
n Social interaction abilities & interests: language is a
social act for infants
n Goal: to understand how biology & culture cooperate
What inner resources does the child bring to the
language acquisition task?
n Some general (e.g. ability & desire to interact socially, ability to
n Some specific to language
Something special is going on in
n 5 month old infants can correctly identify humans as the source of speech and
monkeys as the source of monkey calls.
n They can correctly match different kinds of vocalizations to different species.
n The infants looked longer at the pictures of human faces when human speech was
presented and looked longer at pictures of rhesus monkey faces when rhesus
vocalizations were presented.
n BUT infants weren't able to match human-produced non-speech vocalizations, like
laughter, to humans, suggesting that infants are especially tuned at an early age to
some of the functional properties of speech.
n The fact infants were able to correctly attribute even unfamiliar Japanese speech to
humans bolstered the significance of the results.
n Characteristic timing of acquisition: “sensitive period” for some (though not
all) aspects of language learning
n Characteristic impairments of language connected with different genetic
syndromes & sorts of brain damage
n Signed languages of deaf communities everywhere, with characteristic
grammatical properties not so different from those of spoken languages
n Creation of creoles from pidgins, of home sign, and of Nicaraguan Sign
Early Language Acquisition
n Begins in utero
n Infants combine pattern detection and computation abilities
with special social skills to acquire language
n Incremental - first step recognizing sound patterns:
extraordinary capacity to perceive order in language input
Challenges for the infant –
Problems for speech perception
n Sound variation (dialect, gender, tone…)
n Influence of context on sound realization
n (t in Tom, butter, cot…)
n Locating boundaries in stream of speech:
‘seeing’ the auditory edges
A waveform of a sentence. The silences
are not where you would expect them.
n Infant does a detailed analysis of language input to reveal
the predictable patterns in their native language.
n Infant perception is literally warped by exposure to language:
Native Language Magnet theory (Patricia Kuhl)
n This implies neural commitment and can alter future learning.
Repeated experience wires a child’s brain (or rewires it after
Little polyglots become
monlingual speakers of …
n 6 month old ‘Citizens of the World’ become 12 month old
speakers of English, German…
n Japanese l/r, Spanish b/d, examples of distortion of perception caused
by language experience
n These learning strategies are not speech domain-specific:
part of general auditory discrimination ability. Animals can
In interpreting words, what happens after a
word helps reveal its meaning.
n A word about thoughts or emotions usually has several words at
n I hope you will meet me for dinner.
n *I hope the truck?
n A noun phrase is often followed by one word:
n I am taking the number 7 bus home.
n An action verb related to the muscles often ends the sentence:
n I'm going swimming.
n *I'm going thinking.
More nurture … Social Influences
n Presence of a human being has a strong influence on
learning - need a social tutor
n Primed to learn when engaged in social exchanges
Social interaction ‘gates’ computational learning and protects the infant
from meaningless computations. Ensures learning focuses on speech
deriving from humans in child’s environment and not on signals from
What accounts for impact of social
n Increased motivation? Attention & arousal
n Enriched information? Live situations
n What is a social agent?
n Interactive TV? Socially interactive robot?
n Reciprocity (contingency, interactivity)
n Grounded in appreciation of communicative intentions, sensitivity to
joint visual attention and desire to imitate.
n Active participation - arousal facilitates learning & remembering.
n Evolution - forged connections between language and the social
n Learning depends on normal social interest in people & in the
signals they produce.
Nurture is our nature
Motherese / Infant Directed speech (IDS)
n Universality of adult–child speech behaviour & role of adult speaker
in bringing about language in child.
n Motherese : unique acoustic signature – slower, higher average
pitch, exaggerated pitch contours, exaggerated vowels, temporally
n Not just prosodic but also phonetic aspects altered.
programmed to respond to children's sounds in a way that
reinforces early language development
Can facilitate or hinder language development:
n profound effects of post-natal depression;
n maternal responsiveness accounts for a sig. proportion of variance in
later cognitive development; "sensitive contingent social responding”.
n language development at 30 months related to proportion of mother's
speech to the child during shared activities;
n scaffolding role in book reading;
n predictable routine language repetitions.
n Hirsh-Pasek, K. & Golinkoff, R. (2003) Einstein Never Used Flash
Cards. Rodale Press. (Esp. Chapter 4)
n Karmiloff, A. & Karmiloff-Smith, K. (2001). Pathways to Language.
Harvard University Press.
n Gopnik, A., Meltzoff, A., & Kuhl, P. (2000) The Scientist in the
Crib: What Early Learning Tells Us About the Mind. Harper.
n Music, G. (2011) Nurturing Natures: Attachment & Children’s
Emotional, Sociocultural & Brain Development. Psychology Press.