Psychology 100:16Psychology 100:16

Chapter 11: Chapter 11:

Cognitive and Cognitive and Language development Language development

Outline

• Development

> Prenatal Development

> Attachment

Study Question:

• Describe three main questions posed by developmental psychologists.

Age in months0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Lifts head

Rolls over

Chest up, arm support

Bears some weight on legs

Sits without support

Walks holding on to furniture

Stands alone well

Walks alone well

Stands Holding on

Pulls self to stand

Development• Three questions concerning developmental change

– 1) Is development orderly? (Normative development)> e.g., Sequence of motor abilities involved in walking

Development• Three questions concerning developmental change

1) Is development orderly? (Normative development)>Individual development: Emphasis on differences in

development between individuals

>Two methods used by developmentalists Cross-sectional: Study samples from different ages

• Normative, not individual development Longitudinal: Follow a set of individuals over time.

• Can be applied to both normative and individual development

Development• Three questions concerning developmental change

2] Is development stage-like or continuous?> Stage theories: Development is step-like.

cf: Motor development

> Continuous: Change is gradual and continuous..

3] Sources of development: Nature or nurture?> Maturationist

Development is genetically programmed.

> Learning Perspective Change occurs through experience.

> Interactionism Development results from the interaction of biological

predispositions with the environment.

Development

• Prenatal development– Stages of prenatal development

1) Zygote stage: 0 - 2 weeks. After one week, about 100 cells in two layers

1) Skin, hair, nervous system, and sense organs

2) Digesitive/respiratory systems, and glands. After second week, a new layer:

• Circulatory/excretory systems, muscles

Development

• Prenatal development– Stages of prenatal development

2) Embryo stage: 2 - 8 weeks. Development speeds up. After one month:

• Heartbeat, a tiny brain, body structures begin to form.

After second month:• Major features are discernable (fingers, toes,

eyes)• Most susceptible to chemicals causing birth

defects

Development

• Prenatal development– Stages of prenatal development

2) Embryo stage: 2 - 8 weeks. Sexual development: Formation of gonads

• Female by default: ‘y’ chromosome causes development of testes

• Androgens: E.g., Testosterone. Sex hormone produced by testes, which bring about the development of male sex organs.

Development

• Prenatal development– Stages of prenatal development

3) Fetal stage: 2 - 9 months. Development of bone cells

• After 2nd month: 4 cm length, 30 g.• After 3rd month: 8 cm length, 90 g.

Major organs are developed, kicking may begin• After 4th month: 15 cm length, 170 g.

Can feel movements, audible heartbeat sleep/waking• After 6th month: 30 cm length, 700 g.• Seventh month: Critical month, can survive outside womb.• Last two months: Gains about 250g per week.

Development

• Prenatal development– Stages of prenatal development

> Brain development Week 4: Forebrain, midbrain, and hindbrain Week 7: Cortex becomes visible Week 10 - Thalamus and hypothalamus Week 12- Hemispheres

Development

• Prenatal development– Threats to normal prenatal development

> Diet. Most important environmental factor Malnutrition leads to serious cognitive/physical disabilities

> Terotogens. Chemicals, such as drugs, that cause birth defects. Antibiotics ->Prolonged use, e.g. Tetracycline -> Bone/teeth Tranquilizers-> Cleft palette Heroin/ cocaine-> addiction & withdrawal Cigarette smoke->Reduces oxygen, miscarriages, premature

birth.

Development

• Prenatal development– Threats to normal prenatal development

> Terotogens. Fetal Alcohol Syndrome (FAS)

• Deformation of eyes and mouth• Brain/CNS abnormalities• Deformation of heart• Stunted growth • There is no ‘safe’ amount

DevelopmentQuickTime™ and a

TIFF (LZW) decompressorare needed to see this picture.• Brain Development

– Early brain growth

>Growth and localization of function From 350 g (birth) to 1250 g (age 4) Myelination

• Hearing is fully myelinated at birth• Abstract thinking after 20 yrs.

DevelopmentQuickTime™ and a

TIFF (LZW) decompressorare needed to see this picture.• Brain Development

– Early brain growth

>Synaptic connections between areas Infant brain has too many connections

• Synaptic pruning: frequently used connections in the brain are preserved and unused connections are lost

• “Use it or lose it”

Plasticity: Growth of new neurons and new connections

• “Cells that fire together wire together”

DevelopmentQuickTime™ and a

TIFF (LZW) decompressorare needed to see this picture.• Brain Development

– Early brain growth> Critical periods: Developmental stages where

and animal is able to acquire a particular skill or ability Features detectors in cats Feral Children

> Sensitive Periods: developmental stages where a human is primed to acquire a particular skill or ability

Konrad Lorenz

Development

• Attachment – The social and emotional

bond between infant and caregiver.

– Imprinting: An instinctual tendency in some animals that produces a strong attachment to an adult.

Harry Harlow

Development

• Attachment – Harlow’s (1959) study

> Contact comfort: the facilitation in social development observed when an infant is allowed to touch something that is soothing.

John Bowlby

Development

• Attachment– Extremely important for social development

> Bowlby’s theory: There are Innate behaviours that affect the caregiver

Sucking Looking Smiling (very powerful) Crying (very distressful)

Development

Mary Ainsworth • Attachment – Ainsworth’s test.

>Two forms of infant behaviour related to attachment

Stranger anxiety - the distress observed in infants/young children when approached by a stranger.

Separation anxiety - the distress observed in infants/young children when separated from their caregiver.

>The strange situation procedure Caregiver leaves infant, then is reunited. Stranger arrives with or without caregiver

• Attachment – Ainsworth’s test.

>Three patterns of attachment Secure attachment. Preference for mom over stranger

• Cries when mom leaves, stops when returns

-> about 65% - 70%

Anxious-Ambivalent attachment. Tension in relationship m.

• Continues to cry when mom returns

-> about 15 %

Avoidant attachment. Do not cry when left alone.

• Avoids/ignores mom when she returns

-> about 20%

Development

Mary Ainsworth

Development

• Attachment – The Romanian orphans studies

Social DevelopmentDevelopment

• Attachment – The Romanian orphans studies

Social DevelopmentDevelopment

• Attachment – The Romanian orphans studies

Social DevelopmentDevelopment

• Attachment – The Romanian orphans studies

Development

• Attachment – The Romanian orphans studies

>Disorganized attachment. Freezing, repetitive movements, fear.

Development

• Socialization: Parenting styles– Securely attached babies-> Moms respond

quickly

– Attachment to dads>Approximately the same time as attachment to

moms>Develops differently

Moms: Comfort Dads: Play

Development

• Socialization: Parenting styles– Parenting styles

>Autocratic (Authoritarian): Abide by strict standards

>Permissive: Parents do not assert their authority

>Authoritative-reciprocal: Parents exercise their power and accept obligation to respond to child’s point of view

>Cause and effect in parenting styles and children’s behaviour.

Socialization is a two way street