Broad Strokes in Child and Adolescent Neurodevelopment – Cognitive | Emotional | Personality | Behavioural

WHY IS A FOCUS ON NEURODEVELOPMENT IMPORTANT?

Take the following image as an example:

Imagine that the blue circle at the bottom represents birth. The vertical arrow represents a person’s path through life towards the yellow star, representing a successful life; however, one might define that.

Now, for the sake of this example, let’s say that any adverse event (loss, trauma, physical illness etc.) might push a person’s trajectory out on a tangent at a particular angle. We could also say that the angle might change according to the particular type of adverse event, but let’s keep it simple for this example.

Should this happen later in life, their life’s trajectory ends up closer to the blue star. In contrast, if it happens early in life, there is the potential for the trajectory to be pushed so far off course to land the person in a distressing and impairing psychological, emotional and/or behavioural mess.

In this analogy, the role of mental health professionals (among many others) is to try to buffer the person against the effects of such events and help them find their way back towards their desired outcome. This idea highlights children’s vulnerability in their early years and illustrates the importance of early intervention strategies.

Half of all mental disorders start by 14 years and are usually preceded by non-specifc psychosocial disturbances potentially evolving in any major mental disorder and accounting for 45% of the global burden of disease across the 0–25 age span. While some action has been taken to promote the implementation of services dedicated to young people, mental health needs during this critical period are still largely unmet. This urges redesigning preventive strategies in a youth-focused multidisciplinary and trans-diagnostic framework which might early modify possible psychopathological trajectories. [Colizzi et al., 2020]

AREN'T CHILDREN JUST MINI-ADULTS?

In working with children with mental health difficulties, a different paradigm of thought is required. Children are not just mini-adults.

There’s no one-size-fits-all approach. And every answer to a question about child psychiatry or other socio-emotional or behavioural concerns in children and young people should start with something along the lines of:

It depends on the child and their developmental level.

In thinking about the child, the interface of biological, psychological and social factors involved are critical considerations.

Consider the following analogy: A child is a Jenga tower, on a surfboard, in a swimming pool.

Jenga involves attempting to extract individual wooden blocks from a tower of wooden blocks without the tower collapsing.

 

 

Let’s say the tower represents a child, with each wooden block representing some biological or psychological characteristic – be it an anatomical structure, a genetic factor, a physiological process or some temperamental factor.

Most blocks need to be in place for the tower to remain standing, and each block needs to be fairly symmetrical. The more missing or otherwise imperfectly structured or placed blocks, the greater the tower’s likelihood of collapsing.

The surfboard represents the family. For the tower to remain standing, the surfboard’s surface needs to be reasonably flat, the shape of the board needs to be symmetrical enough to be well balanced, and the board needs to be buoyant enough to float in the water. The board’s surface has a direct effect on the tower itself, as genetic and epigenetic phenomena might, and its buoyancy and stability in the water needs to be such as keeping the tower from falling.

And the swimming pool represents the child’s environment- whether it be social, emotional, political, physical, etc. If the water is still, the surfboard can buffer against the small ripples. But if it’s too turbulent, even the most stable board won’t keep the tower afloat.

So, in approaching a child presenting with mental health-related problems, one has to maintain a comprehensive bio-psycho-social perspective to understand the issues at hand adequately.

UNDERSTANDING NEURODEVELOPMENT

In looking at children through a neurodevelopmental lens, and even before thinking about the specifics of normal neurodevelopment, there are some important over-arching concepts to consider.

1.Nature Vs. Nurture

People are always looking for reasons and causes for their own or their children’s suffering. Questions about the influence of genetic factors or the school’s influence, the peer group or parenting practices are often faced when mental health-related topics arise in children.

For millennia we understood, or at least interpreted, mental phenomena in terms of supernatural origins – attributing causes of mental illness to witchcraft or the gods’ wrath.

Hippocrates and Democritus, in ancient Greece, around 460-370 BC, first argued for a biological/body-based cause of psychological suffering and distress.

But it wasn’t until the early 1600s, with Francis Bacon’s work on empiricism, and Rene Descartes’ theory of dualism, later to become the concept of the Ghost in the Machine, that the debate over nature vs nurture really began to take hold.

Within the health sciences, this debate has largely been resolved, and we now know that it is not a question of nature or nurture but rather a combination of each that influences our functioning as humans. (The debate rages on in political discourse, but that’s for another time).

Modern technology has put to rest any doubt of biological factors involved in the mind and behaviour. Research like the London cab driver studies [Macguire et al., 2006] and the Early Childhood Adversity study [Felitti et al., 1998] are great examples of the environment’s influence on not only psychological but also physical and mental health-related outcomes.

But perhaps the prime example of this phenomenon is that of the study of epigenetics, in which environmental factors influence gene expression and consequently phenotype, without actually affecting the DNA sequence itself.

In mental health, the model that answers this convergence is that of the Stress-Diathesis Model. A particular stressor (nurture) acts as a precipitant to the onset of an episode of mental illness in a biologically vulnerable (nature) individual.

2. Developmental Timing and Plasticity / Critical and Sensitive Periods of Development

We no longer understand neurodevelopment to be either a continuous (purely linear) or a discontinuous (strictly stepwise) process. Rather, as with Nature/Nurture, a combination of both- a dynamic process, with considerable variation between individuals.

The concept of a critical period is that of a relatively limited period, beginning and ending fairly abruptly, during which a specific function develops. If the conditions for development are not met during this period, it may not occur at a later date. An example of this is children born with congenital cataracts- if not identified and operated on early enough, they may never develop normal sight.

A sensitive period is when it is easiest for a child to develop a certain skill or concept- a period of optimum or maximum developmental sensitivity. The prime example for this is second language learning – easiest before age 7, but by no means impossible thereafter.

In practical terms, when looking at neurodevelopment, we think about stages and domains.

Stages: 

Stages refer to the child’s age and serve as a guide as to what milestones one might expect to be achieved at any given age. We divide the age range into

• Infancy (0-2)
• Toddlerhood and Preschool (2-5)
• Childhood (6-11), and Adolescence (12-18).
• The age of 18 now seems fairly arbitrary, as we now know that the frontal lobes are still maturing well into the early 20s. (And anyone familiar with the TV sitcom “Friends” will likely agree that adolescence can often extend well into the 30s!)

Domains: 

When we talk about domains, we mean specific functional domains of development.

• Physical
• Cognitive
• Linguistic
• Socio-Emotional
• Behavioural.

For the sake of brevity, the article will review in broad strokes the developmental processes undertaken during the various stages and refer to the important thinkers, theorists and clinicians who have helped to shape our understanding of these concepts historically. Important as it is, the article will exclude physical development from this discussion.

For physical developmental milestones, click to download the checklist PDF from the Centres for disease control and prevention (CDC).

COGNITIVE DEVELOPMENT

From a neurodevelopmental perspective, cognition refers to acquiring knowledge and understanding through thought, experience, and the senses.

Used in this sense, it is essentially an abstraction from the term cognitive function (referring to attention, concentration, memory, language, executive function etc.) as assessed during a mental state examination.

Swiss psychologist, Jean Piaget (1896-1980), pioneered the social constructivist theory of learning, i.e. how people make meaning about the interaction between their experiences and their ideas (not to be confused with social constructionist theories). Or, put more simply, how people learn through reciprocal interactions with their social environment.

Piaget is best known for his theory on the stages of cognitive development in children:

1.Sensorimotor stage (Age 0-2):

• During this stage, children experience the world primarily through movement and their senses. They are completely egocentric during this time, meaning they cannot consider another’s perspective.
• During this stage, they move from simple reflexes to habits and primary circular reactions (reproducing an event that happened by accident, e.g. sucking a thumb), through secondary circular reactions (reproducing events involving other objects, e.g. lifting an object to the mouth), to tertiary circular reactions (trial and error attempts to produce novel outcomes from objects), and finally towards representational thought- developing symbols to represent events or objects – a move towards understanding the world through mental operations, rather than purely through actions.
• During this stage, children develop object permanence – the understanding that an object still exists, even when they cannot see it.

2. Pre-operational stage (Age 2-7):

• Language development is one of the hallmarks of this stage of development. During this stage, children remain egocentric but start to develop theory of mind.
• They are as yet unable to understand concrete logic and are unable to manipulate information mentally.
• However, they start to use symbols to represent physical models of the world around them, as evidenced by their play, e.g. a child might use a wooden block as a toy car or a broomstick as a horse.
• As they move through this stage, children also develop an interest in reasoning and an interest in why things are the way they are and how they came to be, rather than just what they are.

3. Concrete operational stage (Age 7-11):

• During this stage, children develop a better understanding of mental operations. They begin thinking more logically about concrete events but still struggle with abstract and hypothetical concepts.
• They come to develop a sense of conservation- the understanding that a certain quantity will remain the same, despite changes in its container, shape or apparent size.
• One of the best known of Piaget’s experiments was how he illustrated this point by showing children two equal volumes of water in two equal glasses, then pouring one of them into a different shaped glass, and asking children which glass contained more water.

• As children develop conservation, they understand that the water’s volume remains the same, despite the different glass. Children at this stage are capable of inductive logic (going from a specific experience to a general theory, e.g. I get itchy eyes and a runny nose near cats- therefore, I must be allergic to cats) but are not yet fully capable of deductive logic (using a general principle to determine the outcome of a specific event, e.g. A=B and B=C, therefore A=C). Finally, egocentrism is eliminated during this stage.
• Children develop an understanding that someone else may have a different perspective on something than they do, even if they disagree with that perspective.

 

4. Formal operational stage (Age 11-16 and onwards):

• During this stage, young people develop a capability for hypothetical and deductive reasoning. They become capable of abstract thought (thinking about objects, principles and ideas that are not physically present) and metacognition (thinking about thinking).
• Their problems solving attempts move from trial and error to more systematised, methodical and logical approaches.

Other major contributions that Piaget made to psychology were his concepts of schemata (mental or psychological blueprints for particular objects, concepts or operations), and the way we learn through assimilation (adding new information to an existing schema as it is acquired), or accommodation (adjusting a schema to fit in with new information).

Piaget’s ideas and methodologies revolutionised developmental psychology and had an enormous impact on educational approaches and future researchers.

Read Piaget’s article, where he gives lots of examples. 

LANGUAGE DEVELOPMENT

The capacity for complex language is one of the most important things setting humans apart from other animals. It is the foundation on which much of our modern society is built. It has allowed us to interact with each other in highly complicated ways and has allowed for the development of complex narratives forming and responding to deeply entrenched value systems.

To understand the process of language development, one needs to understand both its imperative function and its representational nature (or declarative function).

From an imperative point of view, language serves to communicate our needs and have our goals met. One only needs to think about the powerful, caring reflex elicited by a crying baby to understand how early language development serves to meet needs. The baby cries, and the parent picks her up, soothes her, feeds her, changes her nappie, or whatever the case may be.

As the child grows and develops a greater capacity to control her actions, she learns that certain sounds result in certain responses from her environment. And as she develops further, she refines this ability and learns to forms words to the same effect.

In this way, language comes to serve an imperative function. But it is language’s declarative function, or it’s representational nature, that really sets humans apart from other animals.

By way of example of language’s representational quality, think of a glass. A glass is not inherently called a glass.

We use the word “glass” to represent the object, made of melted sand shaped to serve as a vessel for holding water. And what that requires is a level of abstraction and mental representation.

Age 1 onwards :

• From around age 1, the child learns to name objects in its environment- Mama, Dada, dog, etc. And the rapid growth and development of language in its representational form occur in parallel with the development of abstract thought capacity.

Age 3 onwards:

• The child develops the capacity for dual representation- the recognition that a symbolic object, e.g. a photograph, can be both an object itself and a symbol of something else, i.e. the person or thing in the photo.

By age 5:

• The child has a vocabulary of about 5000 words and can use grammatically complex sentences.

By age 12:

• The vocabulary is up to about 10000 words. Language is ever more sophisticated, again developing in parallel with the child’s cognition- understanding double meanings of words, metaphorical and abstract language, and using shading and nuance in conversation.

SOCIO-EMOTIONAL DEVELOPMENT

Two important concepts related to socio-emotional development are that of emotion regulation and personality development.

Emotion regulation:

Emotion regulation refers to the ability to recognise and identify a particular emotion as it arises (albeit subconsciously) and to be able to exercise sufficient executive control to mount an adaptive and socially appropriate behavioural response.

If one thinks of emotions as our most instinctual and primal drivers of behaviour, seated deep down in the oldest parts of our brains (evolutionarily speaking), it is in part the function of our cerebral cortex, and our frontal cortices, in particular, to exert ‘top down’ control over those drives.

It’s not to stop or squash or repress those emotions, but to allow them to be expressed appropriately.

A two-year-old stamps and screams and bites and spits in response to the anger he feels when he’s not allowed to eat another piece of chocolate after dinner. He doesn’t yet have the capacity to control such a behavioural response.

Whereas the six-year-old only pouts and crosses his arms grumpily. He can recognise the anger but not let it take full control of his behavioural response.

A four-year-old might run out of her dark room at night in response to anxiety precipitated by thoughts of monsters. At the same time, the ten-year-old would remain in bed, in part because she can rationalise her way out of it by reminding herself that monsters don’t really exist, but also because she can tolerate the anxiety that thoughts of monsters produce, without buying into the thoughts and creating a snowballing feedback loop.

As with language developing in parallel with cognitive development, socio-emotional development occurs in parallel with both of these.

A two-year-old has neither the cognitive skills required to control his behaviour in response to his emotions nor the linguistic capacity to express his distress verbally. So an unbridled physical-vocal expression, in the form of a tantrum, is the result.

But as a child learns about emotions, both explicitly and through mirroring, and learns to think about her experience and express her experience in words, she can regulate her emotions and effectively manage her social interactions.

PERSONALITY DEVELOPMENT

Erik Erikson (1902-1994) was a German-American psychologist, perhaps best known for his theory of the psycho-social stages of personality development.

In this theory, a person moves through 8 stages of development throughout life. Each stage is characterised by a psychological crisis, represented by conflicting paradigms, that need to be negotiated and overcome to be instilled with a particular virtue and progress to the next stage of development.

In each stage, an existential question needs to be answered (not consciously) to attain the desired virtue. For this article, the stages up to, but not including early adulthood are discussed.

1.Trust vs Mistrust – age 0-2:

In this stage, the infant is absolutely dependent on the care of others to survive and thus needs to answer the question:

Can I trust the world?

Through having her needs reliably met by her primary caregiver, she learns that the world is a trustworthy place. She is instilled with a sense of hope, that even though sometimes things may go badly in life, the world is by and large a reasonably safe place and that other people are reliable and dependable.

2. Autonomy vs Shame and Doubt – age 2-4:

During this stage, the child develops a sense of individuation, a sense that he is separate from his mother and his environment and has at least some control over himself and his actions. To attain the virtue of will (i.e. the will to venture out and explore the world), he must first answer the question:

Is it ok to be me?

At this age, the toddler starts to gain control over some basic motor functions and tasks- he is toilet trained and can eat and partially independently dress and wash.

He starts to venture out to explore the world and develop interests. If parents or caregivers encourage self-sufficient behaviour, the child develops a sense of autonomy- a sense of being able to negotiate the world and manage problems on his own.

3. Initiative vs Guilt – age 5-8

In early childhood, the child asks

Is it ok for me to do, move, and act?

During this stage, the child builds on her autonomy by learning to master the world around her. She doesn’t simply do, but plans, undertakes, takes on complicated and challenging tasks to gain a sense of mastery.

The courage and independence developed through judgment call on risk-taking behaviour (e.g. throwing things, climbing trees, making new friends) give her a sense of her capabilities and limitations and instils in her the virtue of purpose- a sense of resolve and determination.

 

4. Industry vs Inferiority – age 8-12

During middle childhood and early adolescence, the child starts to look away from his family and towards his peers and the world. He asks:

Can I make it in this world of people and things?

This stage essentially centres around the development of self-confidence, the virtue of competence. He learns and accomplishes more complex new skills (reading, writing, telling the time) and has a growing urge to bring tasks to completion. He looks for opportunities to achieve recognition from family, teachers and peers through reading sentences, drawing pictures and scoring goals.

5. Identity vs Role Confusion – age 12-18

The core task in adolescence is the development of identity. The young person builds on her sense of competence- it is no longer just a question of what she can do in the world, but

Who am I and what can I be?

This is a critical stage in personality development- a crossroads between childhood and adulthood, between what the child has become and who she will go on to be.

The young person forges past experiences with anticipations of the future, and an emerging sense of self develops, emotional and deep awareness of who she is as a person.

If she can establish her identity by understanding broader concepts about how society functions and her role in society, she will develop the virtue of fidelity- the ability to sustain loyalties freely pledged despite the inevitable contradictions and confusions of the value systems.

BEHAVIOURAL DEVELOPMENT

We tend to behave per systems of morals and values. And our morals, more so than our values, tend to drive our social behaviour.

Through reciprocal social interactions, we develop a sense of what kinds of behaviour are considered good, right, and what kinds are considered bad or wrong.

When were are young, egocentric and concrete in our thinking, we act to avoid pain and pursue pleasure.

But as we develop a broader understanding of social systems, we learn to act according to more abstract principles.

Lawrence Kohlberg (1927-1987) was an American psychologist best known for his theory of the stages of moral development, which was an adaptation of Jean Piaget’s cognitive theory.

Kohlberg’s theory holds that moral reasoning and ethical behaviour have six developmental stages, grouped into three morality levels: Pre-conventional, Conventional, and Post-conventional.

Pre-Conventional

Stage 1:

Punishment and Obedience Orientation:

• Centred around the avoidance of punishment. During this stage, the primary driver behind a child behaving in a particular way is to avoid being punished. To her, there is no difference between doing the ‘right’ thing and avoiding punishment. This doesn’t only apply to young children. However – the notion of “It’s ok to do it if you don’t get caught” subscribes to this stage of moral development.

Stage 2:

Instrumental-Relativist Orientation, or Self-interest stage

• Centres around the pursuit of reward. In this stage, the child makes an effort to behave in such a way as to secure the greatest benefit for himself.

Conventional

Stage 3:

Conformity and Interpersonal Accord:

• This is the Good Boy/Nice Girl stage, in which the child acts according to social norms – to secure approval and maintain friendly relations with others.

Stage 4:

Authority and Social Order maintaining orientation.

• There is a shift towards fixed rules and a sense that the purpose of morality is maintaining social order. The interpersonal accord from the previous stage is now expanded to include all of society. Not everyone progresses further in their moral development than this stage.

Post-Conventional

Stage 5:

Social Contract driven stage.

• It is a move away from the rigid fixed rules stage towards a more abstract and flexible perspective. The world is viewed as holding different opinions, rights and values, and what is legally right and morally right are not always the same. A utilitarian perspective is adopted.

Stage 6:

Universal Ethical Principles Driven:

• Understanding that morality is based on principles that transcend mutual benefit. Moral reasoning comes to be based on abstract reasoning using universal ethical principles. Decisions come to be reached not hypothetically in a conditional way but categorically, in an absolute way.

CONCLUSION

This article aimed to discuss neurodevelopment in broad strokes and stimulate thought on children and young people from a developmental perspective.

When we see children or young people in clinics or hospitals, we should be asking ourselves:

Where are they cognitively?

What is their linguistic ability?

What socio-emotional or personality issues are they grappling with?

What is their sense of morality and socially appropriate behaviour?

If we can understand where a young person is developmentally, it goes a long way to understanding how to interpret their particular presentation and how best to intervene.

From a broader perspective, since human brain development is influenced by exposure to early-life experiences, there are sensitive periods when the brain may be more vulnerable, increasing the risk of psychiatric disorders in later life. During these sensitive periods, efforts of mitigation may prove most fruitful in preventing future psychiatric morbidity.

Therefore, proposals have been made towards neurodevelopmental optimisation research (optimising cognitive and emotional health in developing children) as a strategy to inform early intervention strategies. This research should address deprivation, unpredictability, insecure attachment, sleep, diet, and the gut microbiome via carefully timed randomised enhancement trials. [Luby et al., 2020]