Developmental Neuropsychology – Utrecht University 2019-2020
Chapter 1 – Child neuropsychology: theory and practice
Child neuropsychology = the study of brain-behaviour relationships within the context of an
immature but rapidly developing brain and applying this knowledge into clinical practice.
In other words: helps see the links between brain development and cognitive or social-emotional
development + understanding of the effects of brain injury in children to design interventions
Child neuropsychology: historical perspectives
Plasticity, vulnerability, and critical periods
- Vulnerability > the earlier the brain injury, the better the recovery of functioning (outdated!)
- Critical period = the time window during which external influences have a significant effect >
brain injury will have different consequences at different times in development
- Plasticity > very restricted period, not linearly related to age
Non-verbal learning disability (NVLD)
A consistent pattern of neurobehavioural deficits from brain injury in infancy > visual and tactile
recognition problems, psychomotor problems, difficulties managing novel information > intact
auditory perception, rote learning, basic language, reading and spelling.
In short: visual-spatial, motor, and social skills problems + sometimes confused with autism.
Greatest benefit of NVLD theory = linking cognitive characteristics to a neurological explanation.
Developmental stage at insult and cognitive outcome
A heuristic that couples age at insult/lesion, time of testing and time since insult to language
development (stages: emerging, developing, established).
,Age at insult – determines the nature of the cognitive dysfunction
Time since insult – differing performance due to different stage of recovery, or ‘grow into’ problems
Time of testing – comparison to healthy children of the same age, and what skills can yet be tested
Current multi-dimensional theoretical approaches
Cognitive reserve model = children have different brain and cognitive reserve capacities.
Recovery continuum model = risk and resilience factors interact to determine long-term outcomes.
Dimensions of child neuropsychology: a biopsychosocial model
Brain: prenatal – basic structure, postnatal – elaboration + childhood – diffused damage, adult – focal
Environment: cognitive and socio-emotional skill development depend on environmental richness
Cognitive and socio-emotional function: stages of development + deficits showing later in time
Of course, these dimensions interact, making each individual child’s context different.
Conclusions
The field has moved from theories based on adult models of brain lesions > developmental insights
Predicting the outcomes of child brain damage remains highly complex: theories should incorporate
neurological, cognitive, socio-emotional, and environmental knowledge.
, Chapter 2 – The developing brain
Modular organisation = each brain region supports particular cognitive processes (a bit outdated!).
Connectionist view = neural networks underpin a range of complex skills – the whole brain is needed
for efficient executive functioning.
Brain specialisation: not well understood yet + important for understanding neurobehavioural
consequences of early brain lesions.
Equipotentiality view = all brain regions can take responsibility for any function.
Innate specialisation view = key skills such as language are localised at birth.
Modern views:
- Maturational view = developmental sequence of specific regions is genetically determined,
explaining the hierarchical emergence of sensory, motor, and cognitive processes.
- Interactive specialisation view = the emergence of a new skill reflects refinement of
connectivity between regions, not just activity in one or more regions.
- Skill learning view = patterns of brain activation change during learning, with activation
becoming more focal with age: performance and interaction between regions are linked.
Developmental progression of brain development
Prenatal – genetically determined structure > postnatal – elaboration partly influenced by experience
Hierarchical progression
In general, brain development progresses hierarchically with the brainstem and cerebellar regions
developing first, followed by posterior areas, and lastly anterior areas. However, evidence for this is a
bit mixed, as not all development happens hierarchically.
Additive and regressive events
Additive/exponential increase: myelination and formation of dendritic connections. Regressive: initial
overproduction of synapses and dendrites and selective elimination of redundant ones.
Cellular basis of development
Neurons = basic unit of the central nervous system as it is responsible for transmission in the brain.
Glial cells = support neurons by providing nutrients and regenerating damaged neurons.
Neurolation = the formation of the neural tube. Neural tube defects: spina bifida and anencephaly.
Proliferation = neurons intended to form the cerebral cortex are generated.
Migration = neuroblasts (from which neurons derive) move to their permanent location.
Differentiation = cells become committed to specialised systems.
Apoptosis = elimination of cells with poor or unnecessary synaptic connections.
The postnatal period
In the first few years after birth, synaptogenesis and dendritic development peak, afte r which excess
cells are removed until adolescence. Myelination occurs in growth spurts around age 2, 7-9 and 11-
12. White matter volume increases in a linear fashion until a few years into adulthood (20-25).
Delays in myelination > global developmental delay