Top 10 Questions about Child’s Brain Development — Brain Health Series Part 1

Q: Does brain development depend only on genes?

A: No, brain development is the result of a complex interaction between both genes and environment. Brain development begins in utero. Billions of neurons are generated. They migrate from their birth place in the embryo to their final positions. Axons and dendrites grow and connections (synapses) between neurons are formed. These mechanisms are believed to be hardwired, that is determined by genetics. Once connections are formed, activity dependent mechanisms come into play. Whether a connection is strengthened or eliminated will be determined by the activity of this connection, that is, it will depend on the experiences of the baby/child.

An example of how the environment can influence brain development: Rutter et al. (1998) studied Romanian orphans brought to England and adopted before age two (some before 6 months). When assessed on arrival, the babies were shown to be severely developmentally impaired and malnourished. When tested again after several years in the adoptive environment (at age 4), the chil¬dren showed great physical and developmental progress, especially those adopted before 6 months.

Q: So, can a child outsmart his/her genes?
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A: Yes, that can be done says Richard Nis¬bett author of “Intelligence and How to Get It: Why Schools and Cultures Count”. In this interview, Nisbett explores the interaction between genes, school and intelligence: “If our genes largely determine our IQ, which in turn underlies our performance throughout our lives, then what is the role of school?”

In this other interview, exchild prodigy Joshua Waitzkin’s, American chess player, martial arts competitor, and author, explains how a lot depends on learning about learning.

Q: Are babies born with more or with less neu¬rons and synapses than adults?

A: Babies are born with more neurons and thus synapses than adults. In a study con¬ducted in 2007, Abitz, Damgaard et al. compared 8 newborn human brains with those of 8 adult brains and showed that on average, adult neuron estimates were 41% lower than those of the newborn. What happens to these extra neurons and connections then? The answer is synaptic pruning (or neuron pruning).

Synap¬tic pruning is a regulatory process that reduces the overall number of over¬produced neurons by “weeding out” the weaker synapses. A weak synapse is a synapse that is not used much, which shows that experience is an essential part of brain development.

Q: Is under 5 THE ONLY critical period for brain development?

A: No. Brain development is a continuum from birth to age 20 or so. A “critical period” in development is a time, in the early stages of an organism’s life, during which the organism shows a very high sensitivity to some stimuli in the environment. If the stimuli in the environment are present, the organism will develop in a specific way. If the stimuli are not present during the critical period, it may be difficult, or sometimes impossible, to develop some functions. For example, if an infant does not see light during the first few months of life (at least 6 months), nerves and neurons processing visual input will degenerate and eventually die.

The most wellknown example of critical period comes from the Critical Period Hypothesis (Lenneberg, 1967), which states that the first few years of life con¬stitute the time during which language develops easily. After that learning a language is more difficult and usually less successful.

Is it the case however that “everything happens before age 5″? Would age 0–5 be a critical period for all major cognitive skills? No. Development is more a trajectory, a continuum. Brain imaging studies and other research show that the brain is not fully developed until age 18 to 20. In particular, the frontal lobes of the brain the part involved in judgment, organization, planning and strategizing are the last ones to be wired to function like an adult.

Q: What does playing bring to a child?

A: Research has shown that play is crucial to physical, intellectual, and social-emotional development at all ages. This is especially true of the purest form of play: the unstructured, self-motivated, imaginative, independent kind, where children initiate their own games and even invent their own rules. In other words, playing is a powerful method of cognitive and emotional development, for children and adults alike.

Q: Can a child with ADHD be trained to control attention?
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A: Yes. In particular, training working memory has an indirect effect on attention. Many studies have shown that such training can be beneficial to children with attentional problems. More generally, as Michael Posner, a prominent scientist in the field of cognitive neuroscience, explains attention control is complex but can be trained.

Q: Can a child control his/her own emotions?
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A: Parents and teachers tell kids countless times to “calm down” or “pay attention.” But the natural course of a child’s development means that the brain’s circuitry for calming and focusing is a work in progress. Luckily there are ways to help children: Mindfulness meditation training seems to be a very successful tool in helping children manage and boost their emotional intelligence.

Q: Can the arts boost a child’s academic performance?
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A: Some studies suggest that the arts can boost students’ test scores, although the results are not always causal in nature. For instance, psychologist Michael Posner observed the brain activity of children four to seven years old while they worked on computerized exercises intended to mimic the attention focusing qualities of engaging in art. The researchers concluded that the arts can train children’s atten¬tion, which in turn improves cognition.

Q: What is the effect of music on a child’s brain?

A: Does listening to Mozart make children smarter? It turns out that in spite of the publicity it received the so called Mozart effect is supported by very little scientific evidence. However learning how to make music can have positive long-term changes on the brain. Music instruction may boost specific skills that are directly related to music such as fine motor skill but also increase more general skills such as working memory.

Q: What is the effect of video games on a child’s brain?

A: For years, video games have been linked to aggression and violence, with researchers and media reports suggesting that violent games have inspired or even caused violent acts. However not all games are the same. Some games may boost a child’s visual abilities such as the ability to pick out relevant information from a rapid sequence of visual events, or the ability to resolve small details or see faint patterns. Other video games may even boost higher-level brain functions such as empathy: Indeed, video games with positive objectives can actually inspire people to perform acts of altruism.

Dr. Pascale Michelon