EARLY CHILD EARLY CHILD DEVELOPMENT: MYTHS & DEVELOPMENT: MYTHS &

SUBSTANCESUBSTANCE

By By

Michael RutterMichael Rutter

448

22

MYTH - IMYTH - I

It is only in the preschool years that It is only in the preschool years that environmental influences can have a environmental influences can have a lasting biological impact because lasting biological impact because it is it is only then that rapid brain growth occursonly then that rapid brain growth occurs

Wrong Wrong becausebecause

i. brain growth continues into early i. brain growth continues into early adult lifeadult life

ii. experiences later in life have been ii. experiences later in life have been shown to have neural effectsshown to have neural effects

33

PATTERN OF BRAIN PATTERN OF BRAIN DEVELOPMENTDEVELOPMENT

Evidence from post-mortem studies (Huttonlocher)Evidence from post-mortem studies (Huttonlocher)

From longitudinal brain imaging studies (Giedd et From longitudinal brain imaging studies (Giedd et al.)al.)

Findings:Findings:

i. Initial overproduction of neurons & synapses i. Initial overproduction of neurons & synapses followed by selective pruning of non-followed by selective pruning of non-functional connections ('use it or lose it')functional connections ('use it or lose it')

ii. This process occurs in early childhood but ii. This process occurs in early childhood but also in adolescencealso in adolescence

iii. The timing varies in different parts of the iii. The timing varies in different parts of the brainbrain

iv. Considerable individual differences in timingiv. Considerable individual differences in timing

44

Right lateral and top views of the dynamic sequence of GM maturation over the cortical surface

Gogtay N et al. PNAS 2004;101:8174-8179

©2004 by National Academy of Sciences

55

EFFECTS OF ADULT EFFECTS OF ADULT EXPERIENCES ON NEURAL EXPERIENCES ON NEURAL

STRUCTURESTRUCTURE

e.g.e.g.

London taxi drivers & size of the London taxi drivers & size of the posterior hippocampusposterior hippocampus

Neural correlates of violin playingNeural correlates of violin playing

Longitudinal neural effects of learning Longitudinal neural effects of learning juggling skillsjuggling skills

66

Volumetric analysis findings

Maguire E A et al. PNAS 2000;97:4398-4403

©2000 by The National Academy of Sciences

77

Woollett K et al. Phil. Trans. R. Soc. B 2009;364:1407-1416Woollett K et al. Phil. Trans. R. Soc. B 2009;364:1407-1416

88

MYTH - IIMYTH - IIThere is only one sort of biological effectThere is only one sort of biological effect

WrongWrong because there are at least 3 different varieties because there are at least 3 different varieties

i. i. Experience-expectant effects(cf Hubel & Weisel expts on binocular vision & development of the

visual cortex)Termed 'expectant' because in all ordinary circumstances the necessary experiences will always be available

ii. Experience-adaptive effects(cf Barker hypothesis re long-term effects of

restrictions in early growth)Unlike experience-expectant effects, these concern variations within, as well as outside, the normal range. Termed ‘adaptive’ because the body is adapting to the nature of early experience

iii. Experience-dependent effects(cf the adult experience examples)

Unlike the first two varieties, these are not restricted to any kind of sensitive period restrictions

99

MYTH-IIIMYTH-IIIIf there is a neural effect, this will necessarily If there is a neural effect, this will necessarily lead to a permanent change in function. lead to a permanent change in function. Conversely, if there is no neural effect, there Conversely, if there is no neural effect, there can be no permanent change in functioncan be no permanent change in function

WrongWrong because becausei.i. Many examples of recovery following definite brain Many examples of recovery following definite brain

injury injury (cf. eg follow-up of children with cerebral palsy, and lack of (cf. eg follow-up of children with cerebral palsy, and lack of

aphasic features following lateralised brain injury in early aphasic features following lateralised brain injury in early childhood)childhood)

ii.ii. Epigenetic effects that are not a function of Epigenetic effects that are not a function of neuronal growth/pruning neuronal growth/pruning

(cf. Meaney’s studies in rats of archback nursing in infancy)(cf. Meaney’s studies in rats of archback nursing in infancy)

iii.iii. Lasting effects of physical stress on neuro-Lasting effects of physical stress on neuro-endocrine structure & functionendocrine structure & function

(cf. Levine’s studies in the 1960s)(cf. Levine’s studies in the 1960s)

1010

MYTH-IVMYTH-IVEnvironmental effects on the brain Environmental effects on the brain during critical periods of growth are during critical periods of growth are universal and invariantuniversal and invariant

WrongWrong because becausei.i. Good evidence of genetic influences on Good evidence of genetic influences on

environmental vulnerabilityenvironmental vulnerability

ii.ii. Apparently similar experiences may lead to Apparently similar experiences may lead to either ‘steeling’ (ie protective) or either ‘steeling’ (ie protective) or ‘sensitisation’ (re vulnerability) effects‘sensitisation’ (re vulnerability) effects

iii.iii. Some evidence of effects of both social Some evidence of effects of both social context and prior experiencescontext and prior experiences

1111

No maltreatment Probable maltreatment Severe maltreatment

Pro

ba

bil

ity

of

ma

jor

de

pre

ss

ion

ep

iso

de

EFFECT OF MALTREATMENT IN CHILDHOOD ON LIABILITY TO

DEPRESSION MODERATED BY 5-HTT GENE (from Caspi et al., 2003)

s/s

s/l

l/l

.20

.30

.40

.50

.60

.70

0

s/s = short allele homozygousl/l = long allele homozygouss/l = heterozygous

1212

ANTISOCIAL BEHAVIOR AS A FUNCTION OF MAOA ACTIVITY AND A CHILDHOOD HISTORY

OF MALTREATMENT (from Caspi et al., 2002)

-0.5

-0.25

0

0.25

0.5

0.75

1

1.25

None Probable Severe

Low MAOAactivity, n = 163

High MAOAactivity, n = 279

Childhood maltreatment

Composite index of antisocial behavior

(z scores)

1313

EFFECTS OF 5-HTT GENOTYPE ON RIGHT AMYGDALA ACTIVATION IN RESPONSE TO FEARFUL STIMULI (from Hariri et al., 2002)

-0.4-0.3-0.2-0.1

00.10.20.30.40.50.60.70.80.9

11.11.2

Long allele group Short allele group

5-HTT genotype

% B

OL

D f

MR

I si

gnal

ch

ange

1414

MYTH-VMYTH-VEffects of variations in normal Effects of variations in normal experiences are similar to the effects of experiences are similar to the effects of extremely abnormal experiencesextremely abnormal experiences

WrongWrong because becausei.i. Whereas abundant evidence of long-term Whereas abundant evidence of long-term

effects of physical & sexual abuse,effects of physical & sexual abuse, butbut lacklack of evidence of effects of variation in level of of evidence of effects of variation in level of corporal punishmentcorporal punishment

ii.ii. Genetic findings highlight the differences Genetic findings highlight the differences between corporal punishment & physical between corporal punishment & physical abuseabuse

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Common factors model of the Common factors model of the association between corporal association between corporal

punishment and antisocial punishment and antisocial behavior behavior

Jaffee et al., 2004

1616

Common factors model of the Common factors model of the association between corporal association between corporal punishment and maltreatment punishment and maltreatment

Jaffee et al. 2004

1717

PREDICTED CRIME AND MARRIAGE PREDICTED CRIME AND MARRIAGE PROBABILITIES BY AGE PROBABILITIES BY AGE (Sampson et al., 2006)(Sampson et al., 2006)

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QUANTIFICATION OF MARRIAGE QUANTIFICATION OF MARRIAGE EFFECT EFFECT (Sampson et al., 2006)(Sampson et al., 2006)

Reduction in crime rate of age period 17-32 taking into Reduction in crime rate of age period 17-32 taking into account age variation and persistent heterogeneityaccount age variation and persistent heterogeneity

= 36% to 49% (average 43%)= 36% to 49% (average 43%)

Reduction in crime rate of age period 17-7- taking into Reduction in crime rate of age period 17-7- taking into account age variation and persistent heterogeneityaccount age variation and persistent heterogeneity

= 16% to 64% (average 36%)= 16% to 64% (average 36%)

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MYTH-VIMYTH-VIBecause the effects of ‘ordinary’ adult Because the effects of ‘ordinary’ adult experiences do not usually change neural experiences do not usually change neural structure, they are unlikely to have major structure, they are unlikely to have major psychological effectspsychological effects

WrongWrong because becauseReplicated examples of major turning points Replicated examples of major turning points

effects in adult life associated with, for effects in adult life associated with, for example, marriageexample, marriage

2020

MYTH-VIIMYTH-VIIIf early experiences are both probabilistic and If early experiences are both probabilistic and individually varied in their effects, there is no individually varied in their effects, there is no point in focussing interventions especially on point in focussing interventions especially on the early years of lifethe early years of life

WrongWrong because becausei.i. Early experiences come first and may, therefore, Early experiences come first and may, therefore,

shape later experiencesshape later experiencesii.ii. In some circumstances, extreme early experiences In some circumstances, extreme early experiences

may have marekedly enduring effectsmay have marekedly enduring effects

But partially right insofar asBut partially right insofar asa.a. Effective early interventions do Effective early interventions do notnot obviate the need obviate the need

for attention to later experiencesfor attention to later experiencesb.b. Lasting effects of early experiences do Lasting effects of early experiences do notnot mean mean

that effects are fixed and cannot be modifiedthat effects are fixed and cannot be modified

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CHILDHOOD BEHAVIOR AND ADULT CHILDHOOD BEHAVIOR AND ADULT PSYCHOSOCIAL STRESSORS/ADVERSITIES PSYCHOSOCIAL STRESSORS/ADVERSITIES

(data from Robins, 1966)(data from Robins, 1966)

0

10

20

30

40

50

60

Divorced Unemployed 10+ job changesin 10 years

Unskilled/semi-skilled job

Practicallywithout friends

Antisocialboys

Controlboys

%

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SEVERE EVENTS AND DIFFICULTIES IN EARLY SEVERE EVENTS AND DIFFICULTIES IN EARLY ADULT LIFE AND TYPES OF DISTURBANCE AT ADULT LIFE AND TYPES OF DISTURBANCE AT 10 YEARS IN FEMALES 10 YEARS IN FEMALES (Champion et al., 1995)(Champion et al., 1995)

Mean number of events/ difficulties

2323

AN IMPORTANT ‘NATURAL EXPERIMENT’ FOR TESTING CAUSAL HYPOTHESES ON

ENVIRONMENTALLY MEDIATED RISKS

Because: Profound deprivation followed by above average rearing environment provides opportunity to study effects of radical environmental change.

• Children placed in institutions in early infancy(so no selection into institutions on basis of child handicap)

• Duration of deprivation a function of the child’s age at the time of the fall of the Ceauşescu regime

• Longitudinal data allows study of within-individual change

• Change of environment rapid and easily timed

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HEAD CIRCUMFERENCE ON UK ENTRYHEAD CIRCUMFERENCE ON UK ENTRY

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

Entry under 6 mo.

Entry at or over 6mo.

Subnutrition No subnutrition

SD

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OPERATIONAL CRITERIA FOR OPERATIONAL CRITERIA FOR DEPRIVATION-SPECIFICITYDEPRIVATION-SPECIFICITY

1.1. Present before age 6 yearsPresent before age 6 years

2.2. Distinctive features that differ from other patternsDistinctive features that differ from other patterns

3.3. DSP much more common in children experiencing DSP much more common in children experiencing institutional deprivation at age 6 mo, or laterinstitutional deprivation at age 6 mo, or later

4.4. DSP rare in groups not experiencing institutional DSP rare in groups not experiencing institutional deprivationdeprivation

5.5. Persistence to age 11 yearsPersistence to age 11 years

6.6. DSP accompanied by substantial functional DSP accompanied by substantial functional impairmentimpairment

7.7. DSP evident following deprivation DSP evident following deprivation notnot accompanied by accompanied by subnutritionsubnutrition

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CRITERIA FOR SPECIFICITY CRITERIA FOR SPECIFICITY FOR EACH DSPFOR EACH DSP

Q-AQ-A The pattern that is most obviously DSP. The pattern that is most obviously DSP. No additional criteria neededNo additional criteria needed

D-AD-A The next most clear-cut DSP but less The next most clear-cut DSP but less obviously requiring obviously requiring deprivationdeprivation in in addition to institutional addition to institutional care. Also measures less care. Also measures less satisfactory. Essential to require satisfactory. Essential to require persistencepersistence

CI CI Major overlap with other DSPs but also Major overlap with other DSPs but also

I/O I/O found in the absence of institutionalfound in the absence of institutional

deprivationdeprivation

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RATES OF DSP PERSISTENCE TO RATES OF DSP PERSISTENCE TO AGE 15 AND SERVICE USAGEAGE 15 AND SERVICE USAGE

PatternPattern

% %

Persistence Persistence

to 15to 15

% %

Service Service

UsageUsage

Quasi-autismQuasi-autism 100%100% 100%100%

Disinhibited attachmentDisinhibited attachment 76%76% 79%79%

Cognitive impairmentCognitive impairment 95%95% 84%84%

Inattention/overactivityInattention/overactivity 100%100% 91%91%

Pattern spanning all fourPattern spanning all four 83%83% 83%83%

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ASSOCIATION BETWEEN INSTITUTIONAL ASSOCIATION BETWEEN INSTITUTIONAL DEPRIVATION AND DEPRIVATION-SPECIFIC DEPRIVATION AND DEPRIVATION-SPECIFIC

PATTERNS AT 15 YEARSPATTERNS AT 15 YEARS

PatternPattern

PooledPooled

ComparisonComparison

Group %Group %

InstitutionalInstitutional

DeprivationDeprivation

GroupGroup

Quasi-autismQuasi-autism 7%7% 93%93%

Disinhibited attachmentDisinhibited attachment 7%7% 93%93%

Cognitive impairmentCognitive impairment 0%0% 100%100%

Inattention/overactivityInattention/overactivity 0%0% 100%100%

Pattern spanning all fourPattern spanning all four 8%8% 92%92%

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OVERALL CONCLUSIONSOVERALL CONCLUSIONS

1.1. Early years are not determinativeEarly years are not determinative2.2. Nevertheless, early years are particularly Nevertheless, early years are particularly

important becauseimportant becausea.a. They come first, & so many shape later experiencesThey come first, & so many shape later experiencesb.b. In some circumstances extreme environments may In some circumstances extreme environments may

bring about lasting biological effectsbring about lasting biological effects

3.3. Early interventions are not likely to be sufficient Early interventions are not likely to be sufficient on their own: later interventions are also on their own: later interventions are also crucialcrucial

4.4. Much remains to be learned on the key Much remains to be learned on the key elements in effective interventions and on the elements in effective interventions and on the factors that underlie individual differences in factors that underlie individual differences in responseresponse

EARLY CHILD EARLY CHILD DEVELOPMENT: MYTHS & DEVELOPMENT: MYTHS &

SUBSTANCESUBSTANCE

By By

Michael RutterMichael Rutter

448