Chapter 1: Dimensions of Theory & Practice
-Child neuropsychology = brain-behaviour relationships in dynamic context
-Brain insult in childhood = rapidly evolving system alteration of normal developmental processes at neurological & cognitive
level advantages & disadvantages emore flexible & capable of transferring functions = minimal loss of function OR less
able to support efficient attention, memory and learning skills = greater gap between peers
-Address totality of the child (physical, cognitive, psychosocial experiences) = interact to influence recovery dynamic path of
maturation potential of disruption at various stages
-Dimensions of child neuropsychology = foundations from adult models (cerebral localization and integrated brain systems)
= static, mature, unable to accommodate dynamic early cerebral pathology (insufficient)
-Developmental neurology + cognitive psychology map expected changes in child CNS growth spurts in CNS + increments in
cognitive abilities
-Neuro-dimension: CNS in early gestation ongoing development in infancy & childhood
- Prenatal: Structural formation (basic hardware) interruptions = structural abnormalities (dysplasia, spina bifida,
dandy-walker syndrome, AgCC)
- Postnatal development: elaboration of CNS (connectivity) continues into adolescence (incl. dendritic arborization,
myelination, biochemical changes) greatest maturation in anterior cerebral areas (hierarchically: posterior/anterior)
step-wise model of development rather than gradual progression (early infancy, 7-10 yrs, early adolescence)
- CNS injury/insult = infection, environmental factors (malnutrition, sensory deprivation, toxins)
- Dose-response relationship: severe cerebral pathology = greater neuropsychological impairment
- Acquired Disorders = generalized (TBI, HYD, infection, metabolic disorder)/ Focal disorders (e.g. tumor, stroke = rare)
- Specific impairments (aphasias/apraxias) less common in kids generalized disturbances of information processing
(attention, memory, psychomotor skills, EFs) more common
- Discrepancy in recovery between adults & children long-term recovery patterns differ in favor of more mature brain
- Plasticity = damage to immature brain = less significant disability than equivalent insults in adults
- Increased Vulnerability = little advantage for immature CNS
- Transfer of function = cognitive functions subsumed by damaged brain tissue have capacity to transfer to healthy tissue
influenced by timing (pre/post natal) and nature (focal/generalized) of insult
- Prenatal CNS damage may not result in functional transfer but skills may be maintained ineffectually by damaged tissue
developmental delays
- Transfer of skills = crowding leading to generalized depression of neuropsychological functions
- Childhood CNS insult may not be static but may interrupt ongoing maturation in a variety of ways detrimental to long-
term outcomes.
- electrophysiological and radiological techniques measure rate & localization of development over time map
cerebral activation in young children + directly describe brain correlates formulate developmental theories
minimize removal of functional tissue EEGs/ERPs measure temporal aspects of cerebral function EEG = epilepsy +
sleep ERP = sensory / information processing
-Cognitive dimension: early models of cognitive development focus on Piagetian theory hierarchical/stage-like process
preset series of developmental stages (some variation in timing) quality and level of thinking are key characteristics to
change and progress Increase symbolic thought & ability to deal with complex information
- Premotor (birth-2yrs) simple motor & sensory activities, little abstract thought gradual object permanence (WM)
- 2 yrs = symbolic thought (language, communication, imagery) higher level = limited unidimensional & egocentric
- Operational thought (7yrs) reasoning/problem-solving multiple dimensions, mental transformations, emerge EFs
- Formal operations: fully established in early adolescence
- Transitions evident on standard neuropsychological measures timing of growth spurts in myelination, metabolic and
electrical activity are roughly consistent with cognitive progressions
- Theory of generalized progression of cognitive skills through childhood different rates and progressions in specific
domains (motor vs language) development of individual cognitive modalities is not independent
- Rather domain-specific development occurs in cooperation with similar maturation in other systems – (WM & IP)
- multidimensional relation between memory, processing speed, and EFs are jointly responsible for age-related progress.
- Neuropsychological impairment measured against age-appropriate expectations plot development of cognitive skills
through childhood, identify deviations from expected patterns, formulate diagnosis + treatment normative data
- Adult tests for evaluating developing cognitive skills is problematic do not necessarily measure the same skills
children may achieve similar end points using different brain networks or perform poorly due to cognitive deficits
- Interpretation of test performance as indicative of impairments in higher-order skills is problematic in kids poor
performance may reflect expected developmental progress or impairment of lower-order skills or age-appropriate
immaturity of higher order skills.
- Cognitive developmental theory posits that EFs may be developing in infancy but not measurable until late childhood
cannot reliably identifying deficits until later when they should be present and accessible
- 12 might show deficits when impairments have emerged at the time of developmental expectations (leading to
functional dependence) child may grow into their cognitive deficits as the brain matures (does not necessarily reflect
a deterioration in cognitive skills) – may be a consequence of early cerebral insult.