Developmental Neuropsychology Knowledge Clips A.E.M. van Wordragen (u789251)
Early Brain Development
o Primitive forms of neuronal networks can already be found in the fetal brain.
Characteristics of early brain development:
o Hierarchical: in general, brain structures develop in hierarchical order:
Cerebellar > posterior > anterior
o Additive and regressive: many developmental brain processes increase over time
(myelination = additive), other processes show an inverse development with an initial
overproduction and then selective reduction (synaptogenesis followed by synaptic
pruning = regressive).
o In growth spurts: most processes are not linear, but happen with growth spurts that
often lead to overproduction (and later pruning).
Growth spurts are also referred to as sensitive/critical periods
Widows of opportunity but also of risks.
o If there is damage during the prenatal period, it mostly impacts the structure of the brain
(morphology).
o In the postnatal period there growth spurts in the dendrites, synaptogenesis and
myelination. There are no new neurons being made but they are getting more and longer
dendrites.
o Damage during the postnatal period mostly impacts the function of the brain
(interconnections and functional networks).
o Different early disruptions:
Injury: direct injury, too few nutrients/oxygen
Maternal (mental) health: severe depression/anxiety, infections, sickness
Environmental: exposure to toxins, smoking or drug use of the mother
Genetic: genetic disorders
,Developmental Neuropsychology Knowledge Clips A.E.M. van Wordragen (u789251)
o Strength of rapid growth: immature brains are extremely plastic and are able to recover
better. Clinical observations: children often show greater improvement after brain injury
than adults.
The young brain is less differentiated and more capable of transferring functions
form damaged tissue to health tissue (plasticity).
Equipotential = the view that all brain regions are equally able to take
responsibility for any functions (opposite = innate specialization).
o Vulnerability of rapid growth: as a result of dramatic developmental processes in the
brain may be extremely sensitive to environmental influences early in life.
Critical periods: brain damage within a specific critical window may be more
detrimental than later brain damage outside of the critical window.
Functional plasticity may only be restricted to certain sensitive periods.
o The recovery continuum model states that both of the views stated above are true. There
is no strict line between plasticity and vulnerability.
o Early brain damage is very different than adult brain damage.
o There are different stages of development which may influence the recovery of brain
damage in children:
Emerging skills: early stages of acquisitions.
Developing skills: partially acquired abilities, but not fully functional.
Established skills: matured abilities (almost fully localized and therefore more
difficult to transfer the skill).
o Children may ‘grow into’ deficits in later developmental stages. Initially few deficits, but
child runs into trouble when developing skills at a more advanced level. This especially
happens when skills were still emerging during the time of the injury.
o It is harder to make prognoses in early injury in children than in early injury in adults.
o Factors impacting recovery:
U-shape: large, unilateral lesions better than mediate, diffuse lesions
Diffuse is worse than focal
Age/developmental stage
Sex
Psychosocial context > modifiable risk factors
, Developmental Neuropsychology Knowledge Clips A.E.M. van Wordragen (u789251)
Preterm Birth
o Types of prenatal insult:
Preterm birth (PB)
Hypoxic-ischaemic encephalopathy (HIE)
Prenatal stroke (PS)
All of these can lead to cerebral palsy
o Prematurity
Preterm: <37 weeks
Extreme prematurity: <32 weeks
Viable: >24-25 weeks
o Generally, preterm babies have a smaller brain, both in terms of grey and white matter.
o Brain connectivity in preterm babies is different than in term babies, even in childhood
and adolescence.
o Cerebellum (small brain) is especially implicated (less mature and/ore damaged);
disrupted growth is associated with motor issues, cognitive delays and epilepsy. This is
because the cerebellum has a growth spurt in the third trimester of the pregnancy.
o About 1/3 of the preterm born children have multiple medium to severe issues in
several domains:
Psychosocial: ADHD or attention issues, ASS, conduct disorder > an inability to
regulate yourself or stimulation.
Mental: cognitive delays, language problems, school issues.
Motor: cerebral palsy (PS), motor delays.
Physical: growth delays, lower immune response, visual and/or hearing issues,
breathing issues, epilepsy.
o There is not enough research done about interventions for preterm babies. There are
some results with: active partnerships with family (not only parents), start interventions
as early as possible, interventions need to continue post-hospital discharge.
Early Brain Development
o Primitive forms of neuronal networks can already be found in the fetal brain.
Characteristics of early brain development:
o Hierarchical: in general, brain structures develop in hierarchical order:
Cerebellar > posterior > anterior
o Additive and regressive: many developmental brain processes increase over time
(myelination = additive), other processes show an inverse development with an initial
overproduction and then selective reduction (synaptogenesis followed by synaptic
pruning = regressive).
o In growth spurts: most processes are not linear, but happen with growth spurts that
often lead to overproduction (and later pruning).
Growth spurts are also referred to as sensitive/critical periods
Widows of opportunity but also of risks.
o If there is damage during the prenatal period, it mostly impacts the structure of the brain
(morphology).
o In the postnatal period there growth spurts in the dendrites, synaptogenesis and
myelination. There are no new neurons being made but they are getting more and longer
dendrites.
o Damage during the postnatal period mostly impacts the function of the brain
(interconnections and functional networks).
o Different early disruptions:
Injury: direct injury, too few nutrients/oxygen
Maternal (mental) health: severe depression/anxiety, infections, sickness
Environmental: exposure to toxins, smoking or drug use of the mother
Genetic: genetic disorders
,Developmental Neuropsychology Knowledge Clips A.E.M. van Wordragen (u789251)
o Strength of rapid growth: immature brains are extremely plastic and are able to recover
better. Clinical observations: children often show greater improvement after brain injury
than adults.
The young brain is less differentiated and more capable of transferring functions
form damaged tissue to health tissue (plasticity).
Equipotential = the view that all brain regions are equally able to take
responsibility for any functions (opposite = innate specialization).
o Vulnerability of rapid growth: as a result of dramatic developmental processes in the
brain may be extremely sensitive to environmental influences early in life.
Critical periods: brain damage within a specific critical window may be more
detrimental than later brain damage outside of the critical window.
Functional plasticity may only be restricted to certain sensitive periods.
o The recovery continuum model states that both of the views stated above are true. There
is no strict line between plasticity and vulnerability.
o Early brain damage is very different than adult brain damage.
o There are different stages of development which may influence the recovery of brain
damage in children:
Emerging skills: early stages of acquisitions.
Developing skills: partially acquired abilities, but not fully functional.
Established skills: matured abilities (almost fully localized and therefore more
difficult to transfer the skill).
o Children may ‘grow into’ deficits in later developmental stages. Initially few deficits, but
child runs into trouble when developing skills at a more advanced level. This especially
happens when skills were still emerging during the time of the injury.
o It is harder to make prognoses in early injury in children than in early injury in adults.
o Factors impacting recovery:
U-shape: large, unilateral lesions better than mediate, diffuse lesions
Diffuse is worse than focal
Age/developmental stage
Sex
Psychosocial context > modifiable risk factors
, Developmental Neuropsychology Knowledge Clips A.E.M. van Wordragen (u789251)
Preterm Birth
o Types of prenatal insult:
Preterm birth (PB)
Hypoxic-ischaemic encephalopathy (HIE)
Prenatal stroke (PS)
All of these can lead to cerebral palsy
o Prematurity
Preterm: <37 weeks
Extreme prematurity: <32 weeks
Viable: >24-25 weeks
o Generally, preterm babies have a smaller brain, both in terms of grey and white matter.
o Brain connectivity in preterm babies is different than in term babies, even in childhood
and adolescence.
o Cerebellum (small brain) is especially implicated (less mature and/ore damaged);
disrupted growth is associated with motor issues, cognitive delays and epilepsy. This is
because the cerebellum has a growth spurt in the third trimester of the pregnancy.
o About 1/3 of the preterm born children have multiple medium to severe issues in
several domains:
Psychosocial: ADHD or attention issues, ASS, conduct disorder > an inability to
regulate yourself or stimulation.
Mental: cognitive delays, language problems, school issues.
Motor: cerebral palsy (PS), motor delays.
Physical: growth delays, lower immune response, visual and/or hearing issues,
breathing issues, epilepsy.
o There is not enough research done about interventions for preterm babies. There are
some results with: active partnerships with family (not only parents), start interventions
as early as possible, interventions need to continue post-hospital discharge.
