HOW NEUROSCIENCE CONTRIBUTES TO BETTER PUBLIC POLICIES FOR EARLY CHILDHOOD
Charles A. Nelson III, Ph.D. Professor of Pediatrics and Neuroscience Harvard Medical School Richard David Scott Chair, Boston Children’s Hospital Harvard Center on the Developing Child
SÃO PAULO , Brazil 12 September 2012
OUTLINE
I.
How experience affects brain development II. The effects of early psychosocial deprivation on brain-behavioral development
PRINCIPLES OF BRAIN DEVELOPMENT
• Genetics: supplies basic blueprint for brain development. • Experience: adjusts the blue print and shapes the architecture of its neural circuits, according to the needs and distinctive environment of the individual
15 1/2 WKS
22 WEEKS
27 weeks
23 WEEKS
Full term brain
http://medstat.med.utah.edu
~25 WEEKS
Adult
PART II: HOW Does the structure of experience work its way into the structure of the brain?
INDIVIDUALITY IS THE PRODUCT OF BOTH PERSONAL EXPERIENCES & BIOLOGICAL INHERITANCE Genetics specifies the properties of neurons and neural connections to different degrees in different pathways and at different levels of processing. But, because many aspects of an individual’s world are not predictable, the circuitry of the brain relies on experience to customize connections to serve the needs of the individual. Experience shapes these neural connections and interactions but always within the constraints imposed by genetics
EXPERIENCE IS THE PRODUCT OF AN ONGOING, RECIPROCAL INTERACTION BETWEEN THE ENVIRONMENT AND THE BRAIN Specific experiences vary enormously under identical environmental conditions, depending on the history, maturation, and state of the individual’s brain Brain maturity has impact on experience: Different areas of the nervous system mature at different rates Lower level processing areas mature earlier than those at a higher level. Thus, a less mature brain is affected largely by more fundamental features of the environment, such as patterned light or the speech train.
CON’T • As the brain matures and changes with experience, more detailed aspects of the environment influence it.
• Thus, as an individual’s brain changes, particularly during the early developmental periods, the same physical environment can result in very different experiences.
CONCLUSIONS
I. The impact of experience on the brain is not constant throughout life. II. Early experience often exerts a particularly strong influence in shaping the functional properties of the immature brain. III. Many neural connections pass through a period during development when the capacity for experience-driven modification is greater than it is in adulthood. IV. Such phases are referred to as sensitive or critical periods.
WHAT HAPPENS WHEN CRITICAL EXPERIENCES ARE LACKING AT CRITICAL PERIODS OF DEVELOPMENT?
• Standard way to examine role of experience on development is to observe what happens when experience is lacking. • In study will talk about, have focused on early psychosocial deprivation, as this provides a good model system for the millions of children around the world who experience neglect
THE EFFECTS OF EARLY PSYCHOSOCIAL DEPRIVATION THE BUCHAREST EARLY INTERVENTION PROJECT ON BRAIN AND BEHAVIORAL DEVELOPMENT
BACKGROUND
• Brain requires wide-ranging input (e.g., linguistic, cognitive, social, etc.) during critical periods of development. • Experiences exist on a continuum: some children reared in environments that provide all their needs and others in environments that provide next to none of their needs • Study of institutionalized children represents a model system for understanding role of experience in development, as such children are generally profoundly deprived of most experiences.
CHILDREN REARED IN INSTITUTIONS
CHILDREN REARED IN INSTITUTIONS
• Children raised in institutions are at dramatically increased risk for a variety of social and behavioral problems: • Disturbances of social relatedness and attachment • Attention deficit-hyperactivity disorder (ADHD) • Deficits in IQ and executive functions • Syndrome that mimics autism • Growth stunting (next slide)
17 year old girl
14 year old girl
WHY INSTITUTIONAL REARING MIGHT BE BAD FOR THE BRAIN • Insensitive care • regimented daily schedule • non-individualized care • Isolation • no response to distress • unchecked aggression • Lack of psychological investment by caregivers • rotating shifts • high child/caregiver ratio
BASELINE FINDINGS (BEFORE RANDOMIZATION – MEAN AGE=22 MONTHS)
• IQ • Brain
COGNITIVE DEVELOPMENT (AT BASELINE)
Smyke et al (2007), J. of Child Psych. & Psychiatry
EEG ACTIVITY AT BASELINE
institutionalized children
NIG never institutionalized children Marshall, Fox, et al (2004) J. of Cog Neuro
INTERVENTION EFFECTS
• IQ • Brain
WHAT HAPPENS TO DQ AT 42 MONTHS OF AGE FOR ALL THREE GROUPS? Care as usual group
Foster care group
Mean Developmental Quotient (DQ)
120
103
100
86 80
77 60
40
20
0
42 months
Never institutionalized group
HOW DOES DEVELOPMENT QUOTIENT DIFFER FROM CHILDREN IN FOSTER CARE AS A FUNCTION OF AGE ENTRY?
Developmental Quotient (DQ)
95
90
0-18 18-24 24-30 30+
85
80
75
70
0-18
18-24
24-30
30+
Age at placement Nelson CA, Zeanah CH, Fox NA, Marshall PJ, Smyke A, & Guthrie D (2007). Cognitive recovery in socially deprived young children: The Bucharest Early Intervention Project. Science, 318, 1937-1940.
N 14 16 22 9
DOES BRAIN ACTIVITY (EEG) CHANGE AS A FUNCTION OF INTERVENTION AND TIMING?
FCG > 24
CAUG 3.80μV2
NIG
FCG < 24
2.44μV2
Vanderwert et al (2010) PLoS One
SUMMARY
• Institutionalization has a very detrimental effect on cognitive and brain development. • Foster care appears to be effective in improving cognitive function and EEG for those children placed before age 2. • Duration of time in foster care does not influence timing effects. • Thus, timing is everything.
HOW TO ACCOUNT FOR REDUCTION IN BRAIN ACTIVITY? • Perhaps children have fewer brain cells (neurons) or connections between brain cells (synapses) • Performed Magnetic Resonance Imaging (MRI) when children were 8-10 years old
MRI Testing
3 Tesla Magnet
Head Coil
8 Year Old Child
TOTAL CORTICAL GREY MATTER
*
TOTAL CORTICAL GREY MATTER
*
Sheridan, M.A., Fox, N.A., Zeanah, C.H., McLaughlin, K.A., & Nelson, C.A. (2012). Variation in neural development as a result of exposure to institutionalization early in childhood. Proceedings of the National Academy of Sciences
CONCLUSIONS
• Exposure to institutionalization early in life…. • Leads to reductions in brain size (which may account for the reduction in brain activity we have observed in the EEG and perhaps reduction in head circumference). • Has a differential effect on gray vs. white matter, with • Cortical grey matter being unaffected by foster care intervention whereas • White matter volume is increased by foster care intervention • Thus, profound early neglect leads to dramatic changes in brain structure. White, but not gray matter shows improvement after placement in family care.
ATTACHMENT IN BEIP
SECURE VS. INSECURE AT BASELINE
SECURE VS. INSECURE BY AGE OF PLACEMENT 42 MONTHS
Χ2= 10.58 p = .001
ns
ns
A FUNCTIONAL LOOK AT ATTACHMENT: STRANGER AT THE DOOR AT 54 MONTHS •
Caregiver/mother and child answer door (pre-arranged).
•
RA: “Come with me, I have something to show you.”
•
Walk out the door and around the corner to find RA from previous home visit.
STRANGER AT THE DOOR BY GROUP
54 months
8 years
PATHOLOGICAL FORM OF ATTACHMENT: REACTIVE ATTACHMENT DISORDER • Are two types of RAD: • Emotionally withdrawn/Inhibited • Indiscriminately social/Disinhibited
REACTIVE ATTACHMENT DISORDER
RAD WITHDRAWN/DEPRESSED CAREGIVER REPORT
3 2.5 2
CAU
1.5
FCG
NIG
1
0.5 0 Baseline
30 mos
42 mos
54 mos
8 years
RAD DISINHIBITED CAREGIVER REPORT
3 2.5 2
CAU
1.5
FCG
NIG
1
0.5 0 Baseline
30 mos
42 mos
54 mos
8 years
EFFECTS ON TIMING OF PLACEMENT ON INDISCRIMINATE BEHAVIOR
Assessment Age
CONCLUSIONS • Attachment is profoundly compromised in institutionalized children • Foster care ameliorates some attachment disturbances • Earlier foster care is disproportionately effective
PSYCHIATRIC MORBIDITY
INCIDENCE OF MENTAL HEALTH PROBLEMS • The caregiver was administered the Romanian version of the Preschool Age Psychiatric Assessment (Romanian PAPA) when the children in the BEIP were 54 months old. • The PAPA is a comprehensive structured psychiatric interview assessing mental health symptoms and disorders in children ages 2 through 5 years old.
INCIDENCE OF MENTAL HEALTH PROBLEMS
Did the foster care intervention decrease the rates of psychiatric disorders for ever institutionalized children?
ADHD No difference between IG and FCG 25% 20% 15% 10% 5% 0%
ADHD
IG
FCG
NIG
DISRUPTIVE BEHAVIOR DISORDERS No difference between IG and FCG
16% 14% 12% 10% 8% 6% 4% 2% 0%
ODD/CD IG
FCG
NIG
DEPRESSION
5% 4% 3% 2% 1% 0%
Depression IG
FCG
ANY ANXIETY DISORDER
45% 40% 35% 30% 25% 20% 15% 10% 5% 0%
Any anxiety disorder IG
FCG
NIG
GENDER DIFFERENCES AND TOTAL PSYCHIATRIC SYMPTOMS
CONCLUSIONS • Higher rates of psychiatric disorders and impairment in children who have been institutionalized compared with children in the community. • No significant difference in rates of ADHD or disruptive behavior disorders in children in the institution versus those in foster care. • Children in the foster care group had significantly lower rates of emotional disorders, anxiety disorders, RAD, and impairment (trend) than children who remained in the institution. • Being a girl may be a protective factor. • No evidence of effects of timing on rates of psychopathology or impairment.
Zeanah CH, Egger HL, Smyke AT, Nelson CA, Fox NA, Marshall PJ, & Guthrie D (2009). Altering early experiences reduces psychiatric disorders among institutionalized Romanian preschool children. American Journal of Psychiatry, 166, 777-785.
CONCLUSIONS • Brain development begins a few weeks after conception • Most of brain architecture laid down late prenatal and first few postnatal years but adult brain not evident (at least based on MRI data) till early adulthood • Early experience exerts powerful effect on brain and behavioral development, during so-called sensitive periods • What happens early can have a lasting impact many years later, including adult mental and physical health
POLICY CHANGES AS A RESULT OF BEIP
CHANGES IN ROMANIA • Passed legislation forbidding institutionalization of any child <2 years (unless severely handicapped) • Began to close down institutions (from 100,000 children in 2000 to <30,000 in 2011) • Began network of foster care
CHANGES ELSEWHERE IN THE WORLD • Based on the scientific findings of BEIP • Our foster care program is being exported to several countries • Is a movement towards closing down institutions • The EU recently (June, 2012) was considering legislation that would lead to abandoning the practice of institutionalizing parentless children throughout Europe
UNINTENDED CONSEQUENCES: UNANTICIPATED POLICY CHANGES • In Romania, rush to deinstitutionalize children meant Government hadn’t considered changes in child welfare and child protection. Thus, many children were placed with their biological families who didn’t want them, yet there was little monitoring of these placements • Government established foster care but failed to put the resources necessary to create good foster care, and as a result, many gov’t foster care homes were not ideal • Government failed to put effort in preventing child abandonment • Under political pressure, Government (in 2002) banned all international adoption. Since there was little in the way of domestic adoption, this led to many children being placed in foster care, which is really a temporary placement.
BOTTOM LINE • Let’s learn from the science • Let’s inform policy makers, politicians, and clinicians about the disadvantages of raising children in institutions and the benefits of raising them in families • And let’s inform these same groups that there are lessons learned from BEIP that extend to all children at risk for substandard parental care. – Duration of time spent in early adversity powerfully influences later development – Age of child when removed from adverse environment and placed in “good” home also critical in influencing outcome – Early adversity can have life-long effects on both psychological and physical development; thus
• First years of life are important
EFFECTS OF EARLY EXPERIENCE LAST A LIFE TIME
THE END