1. Infant & Toddler Development
Whittney Smith, Ed.D.
Adelphi University

2. Brain development starts early….
Brain cells (neurons) form in first months of fetal development
Born with 100 billion brain cells
Enough brain cells to learn just about anything – no more are developed after birth
Growth of scientific research and technology to better see and understand brain development. Neurobiology.
Affects all domains of development. 2

3. ... In Utero

4. FUNCTIONS OF THE BRAIN Motor area Sensory area Taste Language Speech
Intellect, logic, reasoning
Taste
Language
Speech
Hearing
Vision
Balance
Emotional Regulation 3

5. The Brain... Hearing, language, memory, social -emotional function
Self-regulation, problem solving, goal setting, social cognition
Vision and perception
Sensory motor perception,
spatial abilities

6. Neurons – brain cells
Dendrites pick up chemical signals across a synapse and impulses travel the length of the axon.
Each axon branch has a sac containing neurotransmitters at its tip.
The electrical impulse causes the release of the neurotransmitters which then stimulates or inhibits neighboring dendrites – like on/off switch.
Myelin – fatty substance coating axons. Acts as electrical insulator; essential for proper information flow, and speek transmission of signals. Although mostly genetic, some factors such as malnutrition can adversely affect myelin. 4

7. Myelination Speed of connection
Begins at birth, rapidly increases to 2-years old
Continues to increase more slowly through 30- years-old

8. Brain Connections 15,000 synaptic connections for each cell.
Signals can be sent to other cells at speeds of more than 200 mph.
Connections (synapses) grow and change as a result of stimulation from the environment.
Brain’s circuitry or “wiring” 5

9. Early Experiences are Crucial
Most brain cell connections are made in 1st year.
By age 3, 80% of synaptic connections are made.
Connections decline after this time to age 10.
During first 10 yrs., brain is twice as active as adults.
Then growth levels off & pruning begins.
Experience shapes the way circuits are made in the brain. 6

10. Use it or Lose it What is not used is pruned.
What is used develops stronger connections.
Develops in “spurts” when the brain is best equipped to learn certain skills. 7

11. Human Brain at Birth
6 Years Old
14 Years Old

12. 2 Months
5 Days
1 Year
28 Years
If children do not receive stimulation, brains will appear less developed. 9

13. Early Brain Development Nature & Nurture
Behavioral and brain development are interrelated.
Interdependent factors: genetics, experience, relationships, health, and nutrition
60% of nutrition is used by the brain during the first year --- decreases to 30% by age 3. 10

14. Early Brain Development
Quality of relationships and experiences in first 3 years has deep and lasting impact on how the brain gets “wired”.
Sets foundation for development in every aspect of life.
Most developmental achievements occur naturally.
Progresses in a non-linear fashion. 11

15. Brain Development: Windows of Opportunity
By Age 2 – emotional control
By Age 2 – social attachment
By Age 5 – motor development
Birth to 10 years – language skills
Birth to 4 years – visual development
Birth to 4 years – math and logic skills
3 to 10 years – music 13

16. 14

17. Attachment Theory Ainsworth, 1973; Bowlby, 1969 Harlow’s Monkeys
Bowlby defined attachment as a “lasting psychological connectedness between human beings”
provides an explanation of how the “parent- child” relationship emerges and influences subsequent development.
Harlow’s Monkeys

18. Hierarchy of Brain Development
Abstract thought
Concrete thought
Logic/Reasoning
Affiliation
Attachment
Contextual Memory
Sexual Behavior
Emotional Reactivity
Arousal
Appetite/Satiety
Motor Regulation
Blood Pressure
Sleep
Temperature
Heart Rate
Breathing
FOREBRAIN
Cortex
“Executive Center”
MIDBRAIN
Limbic
“Emotional Center”
Brain grows in sequential fashion from bottom to top, or from least complex part (brainstem) to more complex area (cortex).
From bottom up:
Brainstem – impulses and reflexes.
Cerebellum – behind brainstem
Midbrain – top of brainstem; movement and balance
Limbic – central part of the brain
Cortex – top layer; includes language, decision making. “Executive control”.
Cerebral cortex contains 80% of neurons. Least developed at birth. Keeps developing through adolescence. More sensitive to experiences than other parts of the brain.
HINDBRAIN
Cerebellum &
Brainstem
“Alarm Center” 15

19. Brain Hemispheres
Left side --- positive emotions, language, approaching new situations or ideas.
Right side --- negative emotions, intense emotions, creativity.
Right hemisphere has growth spurt in first 1½ years, and is dominant for first 3 years.
Early attachment experiences may impact development of the right brain.
Healthy right brain activity supports mental health throughout lifespan. 16

20. Brain Hemispheres...

21. Deficits that occur in the early years may be overcome with later enrichment, though the process will likely be more difficult. Among the most important windows are those involving emotional and social development. Brain has plasticity and can recover over time.

22. Two Basics the Developing Brain Needs
Safety
Positive Experiences 18

23. Early Negative Impact...
…on brain growth, development and behavior during pregnancy, infancy or early childhood:
Inadequate nutrition
Drugs
Alcohol
Toxins (smoking, lead, chemicals) 19

24. A Dangerous Combination of Experiences
Lack of critical early nurturing
Chaotic and cognitively impoverished environments
Pervasive physical threat
Watching violence
Early, frequent, and
intense stress 20

25. Deprivation
Brain activity of a normal 5-year-old child (left) and a 5-year-old institutionalized Romanian orphan who was neglected in infancy (right).

26. Stress & Development
When stressed, brain releases the chemical Cortisol.
High levels of Cortisol can slow brain development and child may experience more cognitive, motor, and social delays.
Hyper-alert or sensitive, irritable, fearful 21

27. A Safe Environment for Brain Development
Reduce stress by making child’s world safe, secure and responsive.
Remove any physical threats.
Responsive to crying.
Predictable daily routines.
Adequate nutrition & hydration. 22

28. Positive Experiences for Building the Young Brain
Loving care & touch
Consistent, individual attention
Everyday, simple activities
Exposure to new experiences
Understanding of child development
Talking
Music
Limited television
Balance – paying attention to the whole child
Read and respond to child’s cues
One size doesn’t fit all
Know child & what he/she is capable of doing 23

29. Stimulation
Overstimulation may result in frustration, stress, or withdrawal.
Too many new experiences at once may be overwhelming and won’t help development.
Child needs time to process what he/she has learned. 24

30. Learning
Children with a secure bond to caregivers are more ready to learn.
Children learn by doing.
Fancy, expensive toys, videos, and flash cards are not necessary.
Repetition in a variety of ways
– modeling, actions, verbally, etc. 25

31. Language
Children exposed to lots of language in reading, singing, and talking develop more neuron connections in the brain area that handles language (temporal lobe).
Children not involved in lots of verbal interaction have brains that are measurably less developed. 26

33. Thinking
Exposure to lots of language is directly linked with advanced thinking skills.
Toddlers understand and can solve more difficult problems at a younger age than children in poor quality environments. 27

34. Physical Activity
Toddler brains thrive with the opportunity to climb, play, splash, and run.
Exercise actually causes the parts of the brain that control movement to develop more neuron connections.
For example, leaving a child in a playpen or in front of TV all day slows motor development.
Importance of play. 28

35. Emotional Control
Brain development helps determine a person’s emotional tendencies.
Infants raised with inconsistent routines, changing caregivers, and stressful environments are more anxious, impulsive, may be less caring toward others, and have fewer problem-solving skills. 29

36. Crying Crying –communication of emotion; response to distress
Colic (1 in 10 infants; birth – 12 weeks - Extended periods of intense crying
Cause unknown (Immature nervous system; Hyper-sensitivity; Digestive problems)
Soothing
Swaddling – tight wrapping of baby in cloth
Touch
Soft, rhythmic sounds
Vibration

37. Crying Disorders
Prolonged crying exposes the brain to high levels of cortisol, adrenaline, and other damaging chemicals.
Damage to hippocampus (memory)
Reduced levels of vasopressin and serotonin
Reduced levels of emotional regulation
Impaired memory
Increased levels of aggression/violence/bullying
Increased levels of anxiety disorders

38. Self Regulation
Strategies for adjusting emotional state to a comfortable (adaptive) level of intensity in order to accomplish goals
Infants: withdrawal, distress, crying -- need soothing
4 months: shift focus of attention
1 year: approach/retreat from stimulus
Parent response to distress is important
Sympathetic - child more easily soothed, more self- regulated
Non-responsive (wait to intervene) - child enters into rapid, intense distress; harder to sooth; doesn’t develop self-regulation

39. Self-Regulation Continued...
When an infant’s needs are met, they can focus on the world around them and explore.
Their brains take in and adapt to stimulation from the external world.
When they aren’t met, they become fixated on trying to get their needs met.
They stop exploring and shut out other stimulation from the external world.

40. Infant/Early Childhood Mental Health
Synonymous with healthy social and emotional development.
Capacity to experience, regulate and express emotions.
Infant characteristics – biological influences, individual differences.
In various contexts within which caregiving takes place – social & cultural.
Focuses on unfolding infant-parent relationship.
Play & exploration are crucial activities for young children. Play during development parallels the sequential neurodevelopmental process. 30

41. What Science Tells Us
Early relationships have permanent effects on brain development, health, and later mental health.
Social-emotional and physical health are inseparable in the very early years.
Responsive caregiving can mediate the effects of some chronic health conditions, e.g., prematurity, poverty.
Social and emotional development is strongly linked to success in school (and beyond).
Intervention can be effective; children and adults can recover. 31