The Process of The Process of DevelopmentDevelopment

John Sargent, MDJohn Sargent, MD

Objectives of this lecture – Objectives of this lecture – to learnto learn

1.) Framework for understanding 1.) Framework for understanding developmentdevelopment

2.) Skill progressions through 2.) Skill progressions through developmental processdevelopmental process

3.) Aspects of family and 3.) Aspects of family and community that promote community that promote developmentdevelopment

Neurobiology of Neurobiology of developmentdevelopment

Neural tissues begin development Neural tissues begin development and differentiation at 2 weeks and differentiation at 2 weeks gestationgestation

By 8 weeks cells begin to divide into By 8 weeks cells begin to divide into cortical and subcortical neuronscortical and subcortical neurons

Between 12 and 20 weeks neurons Between 12 and 20 weeks neurons migrate toward cortical destinationmigrate toward cortical destination

The next step is connections The next step is connections among neurons occurring among neurons occurring throughout central nervous throughout central nervous systemsystem

These connections are refined to These connections are refined to organize cortical circuits and organize cortical circuits and subcortical structures (24 to 28 subcortical structures (24 to 28 weeks gestation)weeks gestation)

Number of neurons in humans Number of neurons in humans peaks at 28 weeks gestation peaks at 28 weeks gestation (40% more than in adult)(40% more than in adult)

Further processes occurring Further processes occurring during fetal life include dendritic during fetal life include dendritic growth, synaptogenesis and growth, synaptogenesis and myelinizationmyelinization

Rapid growth and differentiation Rapid growth and differentiation of central nervous system of central nervous system tissues underlies the tissues underlies the vulnerability to toxins, drugs and vulnerability to toxins, drugs and alcohol and nutritional status alcohol and nutritional status during fetal growthduring fetal growth

Continued maturation of central Continued maturation of central nervous system tissue includes nervous system tissue includes both myelinization and synaptic both myelinization and synaptic pruning which continues from pruning which continues from childhood through adolescencechildhood through adolescence

Gray matter formation follows an Gray matter formation follows an “inverted U-shaped curve” with “inverted U-shaped curve” with peaks occurring between 12 and peaks occurring between 12 and 16 years of age16 years of age

Gray matter areas that organize Gray matter areas that organize sensorimotor activity mature sensorimotor activity mature firstfirst

Higher order association areas Higher order association areas that govern language and that govern language and memory mature later in memory mature later in preschool periodpreschool period

Frontal and prefrontal cortex Frontal and prefrontal cortex continue maturing through continue maturing through adolescence into young adolescence into young adulthood reflecting maturation adulthood reflecting maturation in judgment, values, planning in judgment, values, planning and impulse controland impulse control

Developing brain structures Developing brain structures support developing reading and support developing reading and language skills, with language skills, with interference with brain interference with brain development leading to dyslexia development leading to dyslexia

Development of “inhibitory Development of “inhibitory control” – the capacity to control control” – the capacity to control behaviors that conflict with behaviors that conflict with personal and societal norms also personal and societal norms also occurs with age into young occurs with age into young adulthoodadulthood

This capacity is at the heart of This capacity is at the heart of cognitive and emotional cognitive and emotional maturation, including the ability maturation, including the ability to suppress automatic responses to suppress automatic responses in favor of less automatic in favor of less automatic responsesresponses

This capacity relies upon This capacity relies upon activation of prefrontal cortices activation of prefrontal cortices as well as thinning of cortex and as well as thinning of cortex and continuing myelination of continuing myelination of frontostriatal fibersfrontostriatal fibers

The capacity to read social and The capacity to read social and emotional cues, including facial emotional cues, including facial cues depends upon the cues depends upon the developing capacity of prefrontal developing capacity of prefrontal cortex to modulate limbic cortex to modulate limbic activity which occurs during activity which occurs during adolescenceadolescence

Pruning of synaptic connections Pruning of synaptic connections occurs in unused connectionsoccurs in unused connections

Mirror neurons and Mirror neurons and biobehavioral reactivity have a biobehavioral reactivity have a great deal to do with the great deal to do with the development of empathydevelopment of empathy

Cognitive processing Cognitive processing improvement is also related to improvement is also related to enhanced myelination increasing enhanced myelination increasing the speed of neuronal the speed of neuronal transmission and communication transmission and communication developed through childhooddeveloped through childhood

During infancy the infant’s During infancy the infant’s capacities – smell, suck, grasp, capacities – smell, suck, grasp, capacity to be comforted capacity to be comforted reinforce maternal investment reinforce maternal investment and careand care

Further infant abilities – gaze, Further infant abilities – gaze, smile, nuanced cry, social smile, nuanced cry, social engagement, snuggle, pleasure engagement, snuggle, pleasure upon satiation further reinforce upon satiation further reinforce parental engagementparental engagement

The influence of post partum The influence of post partum depression, chaotic home life, depression, chaotic home life, domestic violence, parental domestic violence, parental substance abuse can be substance abuse can be significant especially in early significant especially in early childhoodchildhood

Attachment relationship between Attachment relationship between child and caretaker also child and caretaker also significantly promotes and significantly promotes and regulates developmentregulates development

Secure attachment is a Secure attachment is a description of a relationship that description of a relationship that the child trusts to bring hurt and the child trusts to bring hurt and emotional distress to, trusting emotional distress to, trusting that the adult will assist with that the adult will assist with calming and regulationcalming and regulation

In a secure attachment In a secure attachment relationship the child is upset, relationship the child is upset, the parent becomes upset, calms the parent becomes upset, calms herself and the child calms in herself and the child calms in responseresponse

2 types of insecure attachment 2 types of insecure attachment relationships have been relationships have been described – avoidant and described – avoidant and resistantresistant

Avoidant children suppress Avoidant children suppress emotion while resistant children emotion while resistant children persist in being upsetpersist in being upset

In situations of abuse children do In situations of abuse children do not develop a unified strategy not develop a unified strategy for regulating disruption and for regulating disruption and behave in an erratic and behave in an erratic and dysregulated fashiondysregulated fashion

Secure attachment leads to more Secure attachment leads to more social capacity, successful social capacity, successful regulation of emotional upset, regulation of emotional upset, improved peer relationships and improved peer relationships and improved behavior regulation in improved behavior regulation in schoolschool

Parental connections also lead to Parental connections also lead to optimal cognitive development optimal cognitive development in first 2 years of lifein first 2 years of life

Neural plasticity facilitates Neural plasticity facilitates recovery from early recovery from early maltreatment, parental loss and maltreatment, parental loss and early adversity of other typesearly adversity of other types

Plasticity is facilitated by Plasticity is facilitated by consistency, availability of consistency, availability of support and coherent family support and coherent family narrativesnarratives

Competency, novelty and praise Competency, novelty and praise drive developmentdrive development

Capacity to do things and Capacity to do things and consistent availability of consistent availability of parental support assist parental support assist navigation of insecurity navigation of insecurity associated with new challengesassociated with new challenges

Development leads to new skills – Development leads to new skills – language, peer relationships, language, peer relationships, learning and following rules, learning and following rules, gaining success in school and on gaining success in school and on playgroundplayground

Parental availability and Parental availability and responsiveness play significant responsiveness play significant roles in reinforcement of roles in reinforcement of children’s developing skillschildren’s developing skills

Important aspects of the Important aspects of the community that support community that support

development includedevelopment includeA.) Pediatric care, child mental A.) Pediatric care, child mental

health carehealth care

B.) Access to safe and supportive B.) Access to safe and supportive child care and preschoolchild care and preschool

C.) Early childhood intervention to C.) Early childhood intervention to support maximal developmentsupport maximal development

D.) Home visiting, supportive D.) Home visiting, supportive neighborhoodsneighborhoods

E.) Adequate effective schools E.) Adequate effective schools with committed engaged with committed engaged teachersteachers

F.) After school opportunitiesF.) After school opportunities

G.) Engaging spiritual G.) Engaging spiritual communitiescommunities

H.) Safe neighborhoods, meeting H.) Safe neighborhoods, meeting places & playgroundsplaces & playgrounds

I.) Coaches, leaders and programs I.) Coaches, leaders and programs to build and develop individual to build and develop individual talentstalents

J.) Groups (like 4-A, scouts) which J.) Groups (like 4-A, scouts) which support group participation and support group participation and group successgroup success

Be aware of the role of Be aware of the role of temperament and intrinsic temperament and intrinsic capacities in engaging in family capacities in engaging in family and community supportsand community supports

Development is based on genetic Development is based on genetic endowment influenced by endowment influenced by environmental circumstancesenvironmental circumstances