How does the brain change as children grow, and what does this mean for children who experience brain injury?
While individuals demonstrate high variability, the young brain is fundamentally different than the adult brain, both in form and in function. Development occurs in different regions at different rates, influenced by the interaction of inheritance, maturation, and experience (Karmiloff-Smith, 2009). Plasticity is defined as the ability to adopt new functional or structural states, and is influenced by heredity and environment. This means, after an injury or other change, the brain can more easily adapt while remaining a strong, efficient basis for supporting functions of everyday life. So, what happens during maturation? And what does that mean for children who experience an early injury to their brain?
Cortical regions associated with language mature relatively late, corresponding with the observation that overall language skill development is protracted over the life span.
Genes guiding growth and development are inherited from a child’s parents. However, we know their expression is mediated by the environment, experience, and maturation (Karmiloff-Smith, 2009). In infancy, the brain is highly interconnected and coarsely coded, but it gradually changes as functions become more discrete in their location and specialization. Large-scale anatomical changes in the brain are caused by three neural processes associated with maturation: the production of new connections among nerve cells, the destruction of superfluous connections among cells, and change to the connective strength between cells. The size of the connections among key areas increases with age and experience. This growth is directly correlated with improvements in language, reading, and memory (Nagy, Westerberg, & Klingberg, 2004), among other skills. Cortical regions associated with language mature relatively late, corresponding with the observation that overall language skill development is protracted over the life span. Essentially, this means that the “hardware” of cognition grows at more or less the same rate as the complexity of the behaviors that we can observe.
…functional evidence from early injury to language-specific brain areas suggests that impairments persist in the pediatric population despite this plasticity…
Some believe that plasticity in youth improves recovery outcomes, since less discrete commitment allows the young, plastic brain to adapt more readily to damage. However, functional evidence from early injury to language-specific brain areas suggests that impairments persist in the pediatric population despite this plasticity, but why? It is possible that children with diffuse injuries are more vulnerable than adults to developmental derailment (Anderson et al., 2009; Daneshvar et al., 2011). Functionally, children with lesions from before birth through the first year of life consistently have the poorest functional outcomes, including reading, spelling, and arithmetic, despite the fact that the first year of life is associated with the greatest opportunity for this kind of cellular and structural flexibility. When young children receive brain injuries, cognitive impairments, including impaired executive function, verbal intelligence, expressive language, and reported difficulty at home and in school, may persist into adulthood. It seems, then, that this flexibility actually makes young brains more vulnerable, as injuries act on developing rather than more static systems of representing information.
It is important for the pediatric clinician to remain vigilant over the long- term duration and to remain open-minded about the nature of deficits that may be observed in children with injury during critical periods of development…
Given this insight, children who experience an early brain injury should be treated cautiously and monitored over time. Common wisdom associated with adult brain injury may not apply. The full extent of consequences of early brain insult may not be evident until many years post-insult, when impairments become apparent in response to increasing environmental demands. Both injury and non-injury factors impact on recovery from early brain insult, and are likely to interact in a complex way that may vary according to severity of insult, age at insult, and time since insult. It is important for the pediatric clinician to remain vigilant over the long- term duration and to remain open-minded about the nature of deficits that may be observed in children with injury during critical periods of development, recalling that the observation that a given domain appears proficient or unaffected by injury to the brain should not preclude its remediation (Diamond, 2009; Karmiloff-Smith, 2009). Optimizing experience and environment through child-based rehabilitation, school-based assistance, and parent support may provide the best opportunity for recovery (Anderson, Spencer-Smith, & Wood, 2011; Centers for Disease Control and Prevention, 2014).
If you believe your child has experienced a brain injury, even a mild injury, such as a concussion, a speech-language pathologist may be able to provide recommendations for supporting his or her academic and social period of recovery.
- Anderson, V. A., Spencer-Smith, M., Leventer, R., Coleman, L., Anderson, P., Williams, J., Jacobs, R. (2009). Childhood brain insult: can age at insult help us predict outcome? Brain, 132(1), 45-56.
- Anderson, V. A., Spencer-Smith, M., & Wood, A. (2011). Do children really recover better? Neurobehavioural plasticity after early brain insult. Brain, 134(8), 2197-2221. Centers for Disease Control and Prevention. (2014). Report to Congress on Traumatic Brain Injury in the United States: Epidemiology and Rehabilitation. Atlanta, GA.
- Daneshvar, D. H., Riley, D. O., Nowinski, C. J., McKee, A. C., Stern, R. A., & Cantu, R. C. (2011). Long-term consequences: effects on normal development profile after
concussion. Physical medicine and rehabilitation clinics of North America, 22(4), 683-700.
- Diamond, A. (2009). The interplay of biology and the environment broadly defined.
Developmental Psychology, 45(1), 1.
- Karmiloff-Smith, A. (2009). Nativism versus neuroconstructivism: rethinking the study of developmental disorders. Developmental Psychology, 45(1), 56.
- Nagy, Z., Westerberg, H., & Klingberg, T. (2004). Maturation of white matter is associated with the development of cognitive functions during childhood. J Cogn Neurosci, 16(7), 1227-1233. doi:10.1162/0898929041920441 [doi]
Melissa Stockbridge is a candidate in the combined program for M.A. and Ph.D. in Speech-Language Pathology at the University of Maryland, under the supervision of Dr. Rochelle Newman. Her primary research interests focus on pediatric brain injury as it relates to linguistic, cognitive, and emotional individual differences and development. She has a M.Sc. in cognitive neuroscience from the University College London, Institute of Cognitive Neuroscience and a B.A. in applied linguistics from the University of Maryland Baltimore County, Honors College.