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Brain: Early Development
Early Learning and the Brain
Development of Young Children with Disabilities#872.514 (61)
Carol Ann Heath
Revised 6.08
Growth of a Brain Network At birth
50 trillion connections
Age 20 500 trillion connections
Ages 3 to 10 1000 trillion connections
Early Brain Process The brain’s task for the first 3 years is to
establish and reinforce connections with other neurons
Neurons mature when axons send messages and dendrites received them to form synapses
Role of Experience Repeated use strengthens brain
connections. If connections are not used, they are
“pruned” away. The brain “grows itself” for whatever
environment it experiences. Most of this experience-based growth
occurs in the cortex (the “executive brain”).
Early Childhood Resource Center
Experiences that Strengthen Connections Are frequent, regular, and predictable Occur in the context of a warm,
supportive relationship Are associated with positive emotion (fun,
excitement, humor, comfort) Involve several senses Are responsive to the child’s interests or
initiative
Early Childhood Resource Center
• Brain cells form in first months of fetal life
• Most brain cell connections are made in the 1st year
• Connections decline after this time to age ten
• The connections (synapses) grow and change as a result of stimulation from the environment
Connections are use dependent Connections develop in a hierarchical manner Deprivation leads to underdevelopment Early life experiences have an important role
in organizing the mature brain
USE ITor
LOSE IT!LOSE IT!
• The brain is not a single system
• Different parts of the brain control different functions
• Neurons react in response to signals from other parts of the brain, the body, or the environment
• Neurons store the information they react to in memory
• Different parts of the brain store information that is specific to the function of that part of the brain
• The brain stores information in a use dependent manner
Abstract thoughtLogicReasoning
AttachmentContextual MemorySexual BehaviorEmotional ReactivityAppetite/SatietyBlood PressureBody Temperature
Motor RegulationBalanceHeart RateBreathing
FOREBRAINCortex
“Executive Center”
MIDBRAINLimbic
“Emotional Center”
HINDBRAINCerebellum &
Brainstem“Alarm Center”
Prenatal: Inadequate nutrition Illegal drugs - alcohol Exposure to toxins Prescription drugs O-T-C drugs Stress
Lack of critical early life nurturing Chaotic and cognitively impoverished
environments Pervasive physical threat Watching violence get what it wants Seeing violence idealized on TV/movies
Early, frequent, and intense stress tunes the brain to set stress regulation mechanisms at high levels.
This often results in a child operating in a persisting fear state.
Increase in heart rate
Increase in blood pressure
Increase in breathing rate
Increase in muscle tone
Release of stored sugar
Hypervigilance
Tuning out of all non critical information
Calm Mild Anxiety Feeling Threatened Terror
abstract concrete emotional reactive reflexive
thinking thinking response response response
cortexlimbic
midbrain
brainstem
The greater the perceived threat, the more primitive the response
Under Any Type of Perceived Threat
(physical, intellectual or emotional)
The Brain:
loses ability to take in subtle clues
reverts to “tried & true” behaviors
becomes more automatic & overreactive
is less able to use “higher order” thinking skills
loses some memory capacity
Low levels = an adaptation to a threatening environment - impulsive, aggressive behavior
Normal levels = clear thinking, social success
High levels = response to an overwhelming environmental threat - fearfulness, anxiety, obsessive-compulsive
25% - 35% of abused children grow up to abuse their own offspring physically or sexually
40% of children who witness either parent striking the other will themselves become spouse beaters
over 1/2 of abused children experience emotional problems in adulthood
The Central Nervous System The CNS forms during the third week of
gestation The outer layer forms an elongated, shoe-
shaped body called the neural plate The plate becomes the neural fold The neural fold closes to form the neural
tube, looks like a a tube with a tail and head
Sequence of Human brain development 3-7 wks Neurulation
Neural tube formationProblems:meningomyelocele (spina bifida) anencephaly
2-3 months Prosencephalic development
Formation of face, cleavage of cerebral hemisphere & lateral ventriclesProblems:holoprosencephalytrisomy 13
3-4 months Neuronal proliferation
If division of embryonic neurons before migrationProblems:Microcephaly
5 months-childhood Period of OrganizationGrowth of dendritic and axonal spines, synapses, glia, selective elimination of processesProblems:
Down syndrome, fragile X syndrome, inborn errors of metabolism, prematurity
Birth-18 months Myelination
Mature myelination of the CNSProblems:Periventricular leukomalacia, congenital hypothyroidism
Brain AnatomyWolfe, P. (2001). Brain matters: Translating research into classroom practice. Alexandria,VA: ASCD.
The Cerebral Cortex Covers the cerebrum (Latin word for brain) Cortex (derived from the Latin word for bark)
resembles the bark of a tree Wrinkled and about ¼ inch thick 6 layers of cells, their dendrites, axons Different areas (lobes) of brain have different
functions
The Process of Learning Synapses make physical and chemical changes Neurons fire together and repeated firings
eventually result in automatic firings, and result in memory being formed
Capacity of the brain to store information is unlimited; 100 billion neurons, each with thousands of dendrites
Learning is the process by which we acquire knowledge and skills
Memory is the process by which we retain knowledge and skills for the future
School learning involves the acquisition of facts and information to build concepts that explain a body of knowledge
Implications for Disabilities Students with learning disabilities have difficulty
focusing, perceiving facts as a temporary effort
Retention is the process when long-term memory preserves information in a way that allows the memory to be located, identified and retrieved for future use.
UNDERSTANDING THE BRAIN
Intellect, logic, reasoning
Motor area Sensory area
Taste
Language
Vision
Balance
Speech
Hearing
Emotional Regulation
Occipital Lobes Located at the lower central back of the brain Primary brain centers for processing visual stimuli Also called the visual cortex Damage can lead to “cortical blindness”
Temporal Lobes On either side of the brain, just above the ears,
are the 2 temporal lobes that curve forward from the occipital lobes
Main function is to process auditory stimuli Composed of several subdivisions that manage
hearing, language, auditory memory Damage can result in aphasia, seizures Wernicke’s area
Parietal Lobes Aids in vision Integrates other stimuli, forming a gestalt
impression from various senses Within this lobe are distinct areas for visual,
auditory, touch, pain, smell, and temperature sensations
Associated with learning disabilities (visual perceptual problems) and ADHD
Frontal Lobes Occupy the largest part of the cortex (28%) Performs the most complex functions Located in the front of the brain Allows movement, thinking, planning, decision
making Allows conscious awareness of these thoughts
and actions
Brain Development 250,000 neurons are added every minute At birth, almost all the neurons that the brain will
ever need are present Brain continues to grow for a few years after birth At 2 years, the brain is about 80% of the adult
size
The Specifics of the Brain During Development The nervous system develops from embryonic
tissue called the ectoderm Neural plate- seen at about the 16th day of
development “Trench” is formed in the neural plate, creating
the neural groove By 21st day of development, neural tube formed
Brain development The rostral (front) part of the neural tubes goes
on to develop into the brain The rest of the neural tube develops into the
spinal cord. 3 major brain areas are formed By end of 7th week, these 3 areas divide again
through encephalization process
Average Brain WeightsAge Brain Weight
20 wks 100 gBirth 400 g18 months 800 g3 years 1100 gAdult 1300-1400 gSource: Neuroscience for Kids- Brain Development
Critical Periods
Critical periods represent a narrow window of time during which a specific part of the body is most vulnerable to the absence of stimulation or to environmental influences.
Human Environmental Science Publication GH6115, August 1, 2001
Sensitive PeriodsSensitive periods are the broad windows of opportunity for certain types of learning. Sensitive periods represent a less precise and often longer period of time when skills, such as acquiring a second language, are influenced.
Human Environmental Science Publication GH6115, August 1, 2001
Early Brain Development Research Does Not….
Support early emphasis on academic skills
Support the idea that more stimulation will result in smarter babies
Indicate that parents need specialized skills to meet their children’s needs
Early Brain Development Research Does…. Support an emphasis on nurturing and early
relationships Indicate that early experiences influence which
brain connections are kept and which are pruned away
Indicate that optimal brain development requires consistent, responsive, and affectionate caregiving
...Reports
Highlighted the need for the adoption of evidence based practices that support young children’s social and emotional competence and prevent/decrease the occurrences of challenging behavior Surgeon General’s Report on Children’s Mental Health,
2000 Off to a Good Start, 2000 Neurons to Neighborhoods, 2001
The Challenge
Aggression in young children is escalating - and is evident among younger and younger children (Campbell, 1990, 1991; Webster-Stratton, 1991, 1998)
Recent studies have reported that 10-25% of preschool children display challenging behavior in the clinical ranges (Jones-Harden, 2000; Joseph, 2001; Webster-Stratton, 1998)
Why Promote Emotional Intelligence?
Increase social and academic readiness of all children
Provide early violence prevention for those children at risk
What Is Emotional Intelligence? Term first used by researchers Mayer & Salovey
in 1990 Concept popularized by Daniel Goleman’s 1995
best seller, Emotional Intelligence: Why It Can Matter More than IQ
Media quickly coined the term “EQ”
Components of Emotional Intelligence
Recognizing & expressing one’s own emotions Emotional & behavioral self-regulation Empathy with others’ feelings Maintaining optimism & motivation
BrainstemBrainstem““alarm center”alarm center”
CorticalCortical““executive center”executive center”
LimbicLimbic““emotional center”emotional center”
Abstract thoughtLogicReasoning
AttachmentContextual MemorySexual BehaviorEmotional ReactivityAppetite/SatietyBlood PressureBody Temperature
Motor RegulationBalanceHeart RateBreathing
Adapted from the Program for Infant/Toddler Caregivers
Limbic System
Developed and functioning at birth “Emotional” brain - actually the front line
of processing basic survival emotions Interactive structures include
Amygdala Hypothalamus Hippocampus
Amygdala
The “sentry” of the brain screens all incoming data
Records and stores emotional tone of memories red flags emotions related to survival
Sends out the alert for fear or aggression
Hypothalamus
Control center for many body functions Coordinates the “fight or flight” response
alerts the sympathetic nervous system triggers the release of epinephrine and
cortisol (through the pituitary and adrenal glands)
Hippocampus
Involved in memory formation One target of the stress hormone cortisol May shrink in response to chronic stress &
depressive disorders Result of excessive cortisol?
Cerebral Cortex
The “strategist” to the amygdala’s “sentry”
Cortex enables us to be consciously aware of emotions and plan how to handle them
Cortex forms most of its brain connections after birth
Frontal Cortex
Influenced by attachment and other social interactions
Grows most rapidly from 8 months to 5 years
Inhibits impulsive action on messages sent by the limbic system
Two Faces of the Frontal Cortex Left frontal lobe
Appears to process “approach” emotions (curiosity, joy)
Right frontal lobe Appears to process “withdrawal” emotions
(anxiety, sadness) Rich and functional emotional life requires
balance of the two
Prefrontal Cortex Located behind the forehead Last area of the brain to finish
developmental process (through adolescence)
Abstract thinking problem-solving predicting consequences using language for self-understanding
Emotional Intelligence: Road Map in the Brain Managing emotions involves promoting effective
connections between the structures of the limbic system & the cortex
Become aware of emotions, then decide how to act, or not act, on them
These skills only begin in preschool years - continue developing actively through adolescence
Effects of Laughter
3 minutes of laughing increases Infection-fighting chemicals Natural killer cells that destroy abnormal cells Plasma interferon which enhances the immune system Cells that attack tumor cells and viruses Antibodies that fight respiratory infections B-cells that cluster near lymph nodes and produce
antibodies that fight harmful microorganisms
Berk, 1989
Laugh More…Live LongerThe “Nun Study”
Danner & Snowdon, 2001
Optimism and positive Optimism and positive emotions expressed in early emotions expressed in early 20’s predicted longevity six 20’s predicted longevity six decades later!decades later!
Emotions are “Contagious”…and human connections serve a central role People in groups laugh 30 times as often
as people alone The average toddler returns between 60 to
80% of his caregiver’s smiles
Zanolli, Saudargas, & Twardoz, 1990;1997
Brain-based Discipline
Two complementary approaches Calming the stress response system limbic
functions Strengthening inhibition and coping skills
cortical functions
Cortical Skills That Help Us Cope with Difficult Situations Recognizing and expressing our emotions
(through language) Emotional self-regulation Behavioral self-regulation Empathy and perspective-taking Maintaining optimism and motivation
Early Childhood Resource Center
Frontal Cortex
Influenced by attachment and other social interactions
Grows most rapidly from 8 months to 5 years
Inhibits impulsive action on messages sent by the limbic system
Brain-based Discipline Self-regulation involves promoting
effective connections between the structures of the limbic system & the cortex
Become aware of emotions, then decide how to act, or not act, on them
These skills only begin in preschool years - continue developing actively through adolescence
Traditional Brain-based
Shifting Our Viewpoint
Behavior problems interfere with the curriculum
Difficult emotions and behaviors are the curriculum for self-regulation
Adults engage in Adults engage in “mutual regulation” “mutual regulation” with children with children
Adults “manage” Adults “manage” children’s behavior children’s behavior through praise or through praise or punishmentpunishment
Traditional Brain-based
Shifting Our Viewpoint
Specific “behavior management” techniques are central
Your relationship with the child is central
Focus on emotional Focus on emotional andand behavior behavior regulationregulation
Focus on Focus on appropriate and appropriate and inappropriate inappropriate behaviorbehavior
Traditional Brain-based
Shifting Our Viewpoint
If one child hurts another, focus on consequences for perpetrator
If one child hurts another, focus on empathy and reparation
Focus on Focus on relationships and relationships and how to nurture themhow to nurture them
Focus on individual Focus on individual child behavior child behavior
Catharsis Theory of Anger Management
Encourage child to get anger “out”
Research indicates this approach increases future aggression
Brain is “practicing” physical aggression rather than calming emotion or inhibiting impulses
School Readiness Skills emotional self-regulation behavioral self-regulation empathy and perspective-taking communicating needs, desires, & interests in
a prosocial way understanding cause & effect sequences interest, motivation, persistence
Early Childhood Resource Center
Importance of Prenatal Period The number of neurons and organization is
determined by heredity (Jabs, 1996) During 3rd week of pregnancy, neural rube
develops, producing neurons which store and transmit information
By end of second trimester, process is complete for the lifetime but neurons are not designated to perform specific tasks
Following Birth While newborns are born with all their neurons,
following birth a new phase begins after birth– wiring phase (Nash, 1997)
Most important factor in developing connections is stimulation, or repeated experience (use or lose)
Early Literacy Early language and literacy (reading and writing)
development begins in the first 3 yrs of life (Marie Clay, educator)
Interactions with literacy materials, such as books, paper, crayons, adults in their lives
Gain significant knowledge of language, reading and writing before school (develop in real settings, authentic learning)
Early Literacy Behaviors
Book handling behaviors Looking and recognizing Picture and story completion Story and reading behaviors
Literacy & Disabilities Experience literacy at a lower level than non-
disabled Interaction of the social environment and the
child’s contributions Expectations lower for children with disabilities Fewer opportunities to develop early literacy
skills
(Saint-Laurent, L., Giasson, J., Couture, C. (1998). Emergent literacy and intellectual disabilities. Journal of Early Intervention, 21(3), 267-281)
Infants can… Recognize their caregiver’s voice Hear different sounds, pitches & tonal
characteristics of speech Experience the way you look into their eyes Benefit from cuddling and touch to assist in
release of hormones for growth See objects and caregivers; at 4 mos. interested
in books
Poverty & Brain Development One in four (24%) of America’s children <3 live in
poverty
2.8 mil children live in poverty and are affected by poor nutrition, substance abuse, trauma, violence