Early Experience Alters Brain Function and Structure

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Early Experience Alters
Brain Function and
Structure
The Neurodevelopmental
effectiveness of the Newborn
Individualized Developmental Care
and Assessment Program
(NIDCAP)
Children’s Hospital Boston
Reading
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Early experience alters brain function and
structure. Als H; Duffy FH; McAnulty GB;
Rivkin MJ; Vajapeyam S; Mulkern RV;
Warfield SK; Huppi PS; Butler SC;
Conneman N; et al. Pediatrics, 2004 Apr; 113
(4 Part 1): 846-57 ISSN: 0031-4005 PMID:
15060237 CINAHL AN: 2005082810 PDF Full
Text
Library Search: eResources, EBSCO Host
Author: Als
Rationale for Study
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Evidence suggests that brain structure and
function are different between medically
healthy preterm infants and their term
counterparts.
Although some differences are explained by
cumulative effect of minor medical
complications, the infant’s sensory
experience in NICU environment may exert
damaging effects on the immature brain and
alter its subsequent development.
Neonatal Intensive Care Unit
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Exposure to bright lights
High sound levels
Frequent noxious interventions
Newborn Individualized Developmental Care
and Assessment Program (NIDCAP)
designed to decrease the discrepancy
between immature human brain’s expectation
and the actual experience in a typical NICU.
Earlier studies (such as on
video)
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Positive results in both behavioural and
electrophysiological functioning of preterm
infants at high risk.
Similar results in low-risk 30-34 week preterm
infants.
Not enough evidence to warrant a multicenter
clinical trial.
Goal of Current Study
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Explore effect of NIDCAP intervention on a
population of low-risk preterm infants.
Neurobehavioural, electrophysiological and
quantitative structural magnetic resonance
imaging methods used in this study.
Care Received
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Control Group: Standard care practice of primary
care nursing and staff-dependent inconsistent
parent inclusion.
Uniform shielding of incubators with white hospital
blankets
Early use of dressing in t-shirts
Side and foot rolls
Liberal provision of pacifiers
Inconsistent nurse-dependent encouragement of
skin-to-skin (kangaroo care) contact and
breastfeeding.
Care Received
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Experimental Group: Developmental care includes:
Daily observations and evaluations of infants’
behaviour with suggestions for staff and parents on
how to support development specific to individual
baby.
Views preterm infant as fetus who finds himself too
early in a technologic hospital environment instead
of the evolutionarily promised mother’s womb.
Behavioural individuality of each infant emphasized.
Developmental Care continued
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Family valued as infant’s most consistent nurturer
Diminishing stress on infant,
Support each infant strengths and competencies
Assuring restfulness, calm breathing and well
modulated color, a well-functioning calm digestive
tract, well-modulated face, extremity and trunk tone,
comfortable rest positions and slowed tempo of all
care giving procedures.
Provision of well-supported relaxation periods.
Developmental psychologist and neonatologist
assigned.
Psychologist and
Neonatalogist
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Provided weekly observations and daily
contact with caregivers, ensuring continuity
and consistency of developmental care.
Ongoing support for the care teams and
parents in jointly planning and delivering
individually supportive care.
Nurses trained in Developmental Care
approach assigned to infants in experimental
group.
Examples of Developmental
Care
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Structure care giving procedures to the infant’s
sleep/wake cycle
Aroused and easily agitated infants? Tuck into a
more curled up position to promote maintenance of
motor tone, energy and restfulness.
Gentle swaddling of infant with soft blanket or
bedding,
Cradling in caregiver’s hands a vulnerable infant
whose breathing easily became labored. Etc.
The Study
Heidelise Als, Frank Duffy et al.
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30 preterm infants
23 to 33 weeks gestational age (GA)
Free of known developmental risk factors
NIDCAP initiated within 72 hrs. ICU
admission
Care continued until 2 wks (corrected)
Classic experimental design
Control group (14) and
Experimental Group (16)
The Study (continued)
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Assessed at 2 wks. and 9 mos. corrected age
2 week assessment included: health status,
growth, and neurobehaviour and
electroencephalogram spectral coherence,
magnetic resonance diffusion tensor imaging
(MRI)
9 months assessment included: health
status, growth and neurobehaviour.
Neurobehaviour
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Assessment of Preterm Infants’ Behaviour
(APIB) and Prechtl Neurologic Examination of
Fullterm Newborn Infant used at 2 weeks.
Measures baby’s ability to modulate
behaviour in relationship to the environment.
At 9 months assessment using the Bayley
Scales of Infant Development, yielding a
mental developmental index (MDI) and a
psychomotor developmental index (PDI) and
Behaviour Rating Scale (BRS)
Neurophysiologic and
Neurostructural Outcome Measures
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Sophisticated measures used of neural
function responsible for complex cognitive
and affective regulatory processes (EEG)
Also, measures of brain development and
structure (MRI and diffusion tensor imaging)
Results
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Experimental group showed significant improvement
in neurobehavioural outcome (APIB and Prechtl)
Motor system modulation and self-regulation were
significant variables.
At 9 mos. 6 infants dropped out of study (1 control
and 5 experimental).
Experimental continued to show significantly better
performance behaviourally.
Emotional regulation, Motor quality and Total scores.
Results Continued
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Neurophysiologically: the experimental group
indicated changes in functional connectivity between
brain regions. Left frontal lobe and occipital/parietal.
Neurostructurally: Overall exploratory comparison
of 4 individual variables revealed an overall trend in
favour of the study’s hypothesis.Left frontal lobe and
occipital/parietal.
The MRI results provide the first evidence of
significant difference in brain structure resulting from
developmental intervention, which means from
sensory experience of the very immature brain.
Issues to Consider
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The Developmental Care Model views the
infant as an active participant who seeks
ongoing caregiver support for self-regulation
during the initial stabilization phase and in the
course of continuing developmental
progression.
Individual differences in thresholds for
stimulation and irritability must be considered.
Issues to Consider:
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The impact of developmental care at an
apparently sensitive period in brain
development.
Even when medically at low risk, early birth
nevertheless may trigger the onset of
sensitive brain developmental periods.
Experience before term may alter not only
brain function, but also brain structure.
Summary
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When infants receive care that is structured
individually based on their own thresholds to
maintain behavioural and motor system
equilibrium, they seem to show improved
outcome as compared with their peers who
experience more standard care.
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