Lecture 5 - Infant Perceptual, Cognitive, and Language Development

Perceptual Development - Vision

It is the last sense to reach full capacity

• Visual development is supported by rapid maturation of eyes and brain visual centers

• Visual Acuity reaches near-adult by 6 months

Depth Perception

The ability to judge objects from one another and from ourselves

• able to see the distances between objects

When does Depth perception begin to aquire?

2-3 months

Role of motion in Depth Perception

Motion provides a lot of information about depth

• it is the first cue (watching people move around)

Role of independent environment - Depth Perception

Plays a vital role in its refinement (360 view), New level of brain organization (crawling)

Gibson and Walk (1960) visual cliff demonstrations

• tested 360 crawling infants (6.5-14 months)

• Children wouldn’t crawl across “deep” side, only 3 out of 36 would (if their depth perception was developed)

Pattern Perception

Preferences - pattern and complex stimuli over plain

Pattern Perception - Contrast Sensitivity

If babies can detect a difference in contrast between 2 patterns, they would prefer on with more contrast

ex) checkers vs more simple patterns

Pattern Perception - Fantz and looking chamber

Infants lay on their backs and look at stimuli on the right and Left

• tested infants ages 10 hours old-6 months

• Infants show a clear preference for human face

“are we born with a template of a human face for survival?”

• others argue for role of early experience

Piaget’s Cognitive-Developmental Theory - Nature of Sensorimotor Stage

(1-2 years)

• infants and toddlers learn and think about the world through their 5 sense and their motor skills

Schemes

psychological structures that organize experience

• more motor based then become more conceptual (for sensorimotor stage)

How does cognitive change take place? - Adaptation

Process of building schemes through direct interaction with the environment

Assimilation

adding new information to existing knowledge systems

• external world is interpret through existing systems

Accomindation

exchanging info between already existing knowledge systems

• new schemes are created, or old ones are adjusted to better fit the environment

Organization

internal process of rearranging and linking schemes

• not interacting with environment

The sensorimotor stage - the circular rotation

means by which infants build schemes by trying to repeat chance events caused by their own motor activity

• focused on themselves rather than the environment

Substage 1 of the Sensorimotor stage - Reflexive Schemes

Exercising reflexes, the building blocks of sensorimotor intelligence (where it all begins)

Substage 2 - Primary circular reactions

1-4 months

circular reactions oriented toward infants own body

• discovery of ones own body then repeating them

Substage 3 - Secondary Circular Reactions

4-8 months

Repeat interesting or novel events in the environment (starting to become interested with objects)

Substage 4 - Coordination of Secondary Circular Reactions

8-12 months

Experimenting-repeating acts with variation

Can lead infants to mischief because they are experimenting

• e.x infant on high chair and keeping dropping everything

You begin to see beginnings of object permenance

Substage 6 - Mental Represenation

The final goal, 18-2 years

Characteristics and Accomplishments of Substage 6

1. Represent the world in a symbolic, conceptual manner

2. Able to create mental representations = internal images of objects, actions, and events

3. Using words and gestures as symbols (waving and saying “bye bye”)

4. Deferred initiation = ability to reproduce the behavior of models no longer present

5. Changes in nature of play: from functional to pretend (make believe)

Deferred initiation

ability to reproduce the behavior of models on longer present

Updated Perspectives on Infant Cognition

• recent research indicated that infants display certain cognitive abilities earlier than Piaget believed

• perhaps Piaget relied too heavily on their displaying knowledge through movement

  • fragile memory and motor skills made them not have object permanence

• Cognitive development is likely gradual, continuous, and uneven

• Expanded methods. New technique = violation of the Expectation method

New approach = core knowledge perspective - infants are born with a set of innate knowledge systems or core domains of thought. Each of these prewired understandings permits a ready grasp of new, related info. A kind of native environment

Violation of Expectation Method

use infants’ heightened attention to or surprise at deviations to infer underlying beliefs

Core knowledge perspective

New approach to infant cognition

• Says that infants are born with a set of innate knowledge systems or core domains of thought. Each of these prewired understandings permits a ready grasp of new, related info. A kind of native environment

Behaviorist Perspective

Believes that language is acquired though operant (reward + punishment)

conditioning and through imitation

problem: unique verbal creations and errors

Nativist perspective

All children possess an innate, biologically-based system for language acquisition called the language acquisition device (LAD)

• LAD contains a set of rules common to all languages

• Newborns prefer speech sounds and human voice

• Universal sequence of language milestones

• Evidence of sensitive periods

• Observations of deaf children

Problems of Nativist Perspective

• can’t identify a single, underlying grammar system

• Early word combinations do not follow grammatical rules

• No anatomical evidence

Interactionist Perspective

language achievements emerge through interaction of innate abilities and environmental influences

Six Characteristics of Infant-Directed Speech

1. a high-pitched, exaggerated expression

2. short sentences and phrases

3. simplification - we use concrete, simple vocab, short sentences

• labeling

• simplifying words (ouchy)

• avoidance of pronouns

• talking about the here and now

4. high proportion of questions and demands

5. Repetition (saying ball many times)

6. Expansions

Joint attention

child attends to same object or event as caregiver

Turn-taking games

demonstrate conversational turn-taking

Preverbal Gestures

help support spoken languages and influence others’ behavior

Components of Prelinguistic Communiation

1. Cooing (vowel sounds) - oooo, ahhh, 2 months

2. Babbling (w/ consonants)- 6 months

3. Intonation (changes in pitch) - 7 months

Language universalist

can distinguish and make all human sounds

Language Specalists

narrows down to what they hear

Nature of first words (8-18 months)

Common types → usually refer to important ppl or objects, familiar actions of outcomes

Production vs. Comprehension

receptive language/comprehension develops ahead of productive language

COMPREHENSION BEFORE PRODUCTION

Holophrastic Speech

use of a single word to convey complete thoughts (mama for everything)

Overextension

defining a word too broadly

overly applying to word

Underextension

defining a word too narrowly

use the word only for one thing (family car is only car)

Vocabulary Explosion

18-24 months

Some but not all infants adding vocab words at a rapid amount

Telegraphic Speech

2 word utterances

(e.g., more juice, mommy, go)

Object Permenance

the understanding that objects continue to exist even when they cannot be seen, heard, or touched

Intermodal Perception

the process of making sense of simultaneous input from more than one modality, or sensory system, perceiving these separate streams of information as an integrated whole

Video Deficit Effect

In toddlers, poorer performance on tasks after watching a video than after seeing a live demonstration

Vygotsky’s approach to infant Cognition

emphasizes that mental development is driven by social interaction and cultural context from birth, rather than solitary discovery

Zone of proximal Development

In Vygotskys theory, a range of tasks too difficult for a child to handle alone but possible with the help of more skilled partners