Development
LANGUAGE ~ SOCIAL
Why Study Development?
 “One great blooming, buzzing confusion” – William
James
(Learning is amazing!!)
 The child is the father of the man
 One way to understand human cognition is start at
the beginning
 Help our understanding of children and the learning
process
Themes of Developmental Psych
 Themes to keep in mind throughout material
 Nature
vs. Nurture
 Nativist vs. Empiricist
 Models of Development
 No development (little adults)
 Maturation
 Readiness
 Stages
 Waves
 Critical periods
Side note: How do you test infants?
 Habituation
 Procedure: Expose baby to
stimulus until he/she no longer
attends at it

Test: Introduce new stimulus

If baby looks longer at new
image, it’s perceived as new.
Language
 Humans have it (almost ubiquitously), animals don’t
 Incredibly difficult to learn

Speech sounds are highly variable:






different speakers
different rates
different genders
accents
different intonation patterns
Speech stream is continuous: the “segmentation
problem”
 Incredibly difficult to learn

Speech stream is continuous: the “segmentation
problem”
Language
 Children develop language fast and effortlessly
Number of Words Said
200
150
100
50
1 year:
1 word
2 years:
300 words
3 years:
1000 words
4 years:
5000 words
5 years:
10000 words
18 years:
words
0
10
12
14
16
Age in Months
18
20
22
60000
Critical Period?
Sometime between age 5 and puberty, language acquisition
becomes much more difficult

“Wild Children” (such as Genie) have difficult time
acquiring language in adolescence

Congenitally deaf children of hearing parents not exposed
to sign language show increased impairments with age

Language capabilities of bilingual adults who acquired
their second language at different ages
Critical Period?
 Performance on a test
of English grammar by
adults originally from
Korea and China was
directly related to the
age at which they came
to the United States
and were exposed to
English
 The scores of adults
who emigrated before
the age of 7 are
indistinguishable from
those of native English
speakers
Language Development
 Skinner (Behaviorism) – stimulus/response model of
language
 Noam Chomsky – “Skinner’s work can be regarded,
in effect, as a reductio ad absurdum of behaviorist
assumptions”



Endless new combinations of words
Children learn rapidly without formal instruction
“Colorless green ideas sleep furiously”
Innateness of Language?
 Chomsky’s Solution
 Universal Grammar: all natural languages share a common
structure that arises from the way our brain is designed to
construct and process language.
 We have evolved specialized mechanisms for
language because communication is advantageous
Problem - “Universal” structure could come from the
constraints of the environment and communicative
needs
Arguments for Innateness
 Fast mapping / mutual exclusivity
 Whole object assumption - “GAVAGAI” experiment
Arguments for Innateness
 Dedicated brain regions – Broca’s and Wernicke’s
areas

Damage to Broca’s area, near the motor cortex, is associated with
difficulties in producing speech

Damage to Wernicke’s area, which is near the auditory cortex, is linked to
difficulties with meaning
 FOXP2 gene

Family missing the gene show
severe speech and language
impairments
General Mechanisms
 We evolved general cognitive/social mechanisms
that support the development of language


Mechanisms not specific to language
Language is the byproduct of genetic traits being selected for
 Word learning constraints – could be result of
cognitive constraints
General Mechanisms
 Statistical Learning
<5%
pre-tty-ba-by
~93%
General Mechanisms
 How quickly could
you pick out a word
from a stream of
speech like the one
shown here?
 It takes 8-monthold infants only 2
minutes
 Social word learning
- That’s a blicket! Wow, a blicket!”
Children only assigned the word “blicket” to a toy if the
speaker is looking at the toy
 Alternative explanation for brain localization –
Interactive Specialization (Mark Johnson)
 Brain regions become specialized through the dynamic
interplay between between input and systems

Congenitally blind children show language activation in visual
areas and not in typical language areas till much later (Rebecca
Saxe)
Social Development
Standing on the shoulders of giants
Social Development
“most, if not all, of the species-unique cognitive skills
of human beings are not due to a unique biological
inheritance directly, but rather result from a variety
of historical and ontogenetic processes that are set
into motion by the one uniquely human, biologically,
inherited, cognitive capacity” - Michael Tomasello
 Ratchet Effect – knowledge shared and built upon
Social Development
 Vygotsky
 Children are social beings, intertwined with other
people who are eager to help them gain skills and
understanding

Humans are seen as unique because of their inclination to
teach each other and to learn from each other

Cognitive development occurs in social interactions

Zone of Proximal Development
Imitation
 Blind imitation – mimicked behavior
 Imitation proper – imitated behavior with attention
to outcome (goal of behavior)
 Goal emulation – imitation with the completion of
unfulfilled goal
 Imitation of use for novel objects (Meltzoff)

Imitation proper – by 14 months – infants repeat action of
touching forehead to a box until it lights up (understand the
goal of imitated action)

Goal emulation –
by 18 months infants are
completing the attempted
action of adults
 Theory of Mind – the understanding that we have a
mind (intentions, desires, knowledge, beliefs) and
that other people have a mind of their own (2-5 yrs)
 Evidence for understanding theory of mind/ other’s
intentions as early as 5-7 months
 Attachment: infant forms a relationship with
caregiver and uses them as a secure base to explore
the world

Ainsworth: Strange situation
Attachment Styles
 Secure - Uses caregiver as a secure base for exploration.
Upset by departure of parent but easily calmed when
they return and can continue to play.
 Resistant – Does not use parent as a secure base, often
stays close to them. Upset when they leave but not
comforted by their return.
 Avoidant – Little affect while playing. No visible stress
upon parents departure, ignores them on return. Treats
the stranger similarly to the caregiver.
 Disorganized – no clear attachment patter. Show
freezing or repetitive behavior.
Bucharest Early Intervention Project
(Photo credit: Charles Nelson, BEIP UNICEF report)