Chapter 9

Intellectual Development in Infants

Chapter Objectives Describe how a baby’s experiences increase

brain function Explain how the brain becomes organized List four abilities that show intellectual growth

in infants Identify specific abilities that babies learn

during Piaget’s first period of learning Name five ways caregivers can encourage

learning Discuss how to choose toys appropriate for

babies of different ages

Chapter 9.1

Early Brain Development

The Structure of the Brain A neuron is a nerve cell

Links between these neurons are formed immediately

Neural pathways are the links that develop between neurons The pathways “wire” the brain so it can control

different body functions and thinking processes Created quickly Maximum number of links is reached by age 10

Parts of the Brain Each section controls a specific function or job

of the body One of the most important parts : Cortex

Part of the brains cerebellum and its growth permits complex learning

As babies experience more input from the world, they brains respond by making more connections As caregivers hold, play, and talk to an infant, the

baby actually uses these experiences to build the brains capacity

Parts of the Brain: Cerebrum Receives information

from senses and motor activities

Controls speech, memory, and problem solving

Most activities occur in the outer layer Cerebral cortex

(cortex)

Parts of the Brain: Pituitary Gland Secretes hormones

that control Growth Metabolism Sexual Development

Parts of the Brain: Brain Stem Controls

Involuntary activities Breathing Heart rate Blood pressure

Parts of the Brain: Spinal Cord Transmits

information from the body to the brain and vise versa

Controls simple reflexes that do not involve the brain

Parts of the Brain: Cerebellum Controls

Muscular coordination Balance Posture

Parts of the Brain: Thalamus Relays sensory

information from other parts of the brain to the cerebral cortex

How the Brain Works Neurons are connected

by axons An axon is the connection

between neurons that transmits instructions from the cell body to another neuron

Axons are coated with a fatty substance called myelin Myelin helps transmit

messages Dendrites branch out

each axon to receive the electrical messages

How the Brain Works Dendrites and axons

do not touch A synapse is the tiny

gap between the dendrites where messages are transmitted

Neurotransmitter is a chemical released by the axon Chemicals look for a

dendrite to attach to but they can only attach to specific receptors

Developing the Brain More pathways give the brain more power

Gives the brain more flexibility The increase connection is the direct result of

sensory input The more the baby interacts with the world, the

more complex the brain’s “writing” becomes

How the Brain is Organized Organization is based on the particular

experiences unique to that child As connections between dendrites and axons

grow stronger, neurons link together They become systems of nerve cells that control

certain groups Systems of neurons work together to influence

how babies see, hear, think, and remember This is how learning takes place Humans learn new behaviors all their life

How the Brain is Organized Connections between

neurons are not permanent

They can be broken when not used often This is called pruning

At the same time connections are being lost, new ones are being made This is called branching

The branching and pruning process helps the brain focus on useful connections and then acquire more skills

Stimulating Infant Brain Development

Speeding the Brain’s Work When a baby is born only

those nerves that control basic instincts, like nursing, have myelin coating

Other axons get a coating of myelin as they child grows Process continues until age

20 Myelin is added at different

times to different areas Which axon receives the

fatty myelin may explain why some children have difficulty learning certain tasks

Myelin is crucial to the speed in which nerves function

Multiple sclerosis is a disease in which the absence of myelin plays a role

Chapter 9.2

Intellectual Development During the First Year