Hijacked :: The Developing Brain



As a fetus develops, neurons are formed and then move to different parts of the brain. The more basic areas of the brain are shaped followed by the more sophisticated areas. The brainstem and midbrain are the first to develop, seeing as they govern the most basic functions like breathing. These autonomic functions can be thought of as automatic—we don't need to consciously tell our lungs to take in air or instruct our stomachs to churn our food. In fact, when a baby is born, she has a nervous system that is very well developed, yet regions such as the limbic system and the cerebral cortex are present yet largely undeveloped.[1] The limbic system—the amygdala, hippocampus, cingulate gyrus, thalamus, hypothalamus, and parietal cortex—is a collection of more complex structures responsible for emotion, behavior, motivation, long-term memory, and smell and is particularly vulnerable to adverse events in childhood,[2] whereas the cerebral cortex plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. These regions will develop later in life. Experience helps to govern which neurons will stay and which will go. Experience will assign priority to certain connections, whereas others will be more passive. Select synapses will become strengthened, whereas others will be discharged.

Chemical messengers such as neurotransmitters transmit information between neurons and cells. This messaging system also makes it possible for young babies to be more than capable of breathing, eating, sleeping, seeing, smelling, making noise, and sensing touch, yet they are highly incapable of regulating their emotions and engaging in abstract thought until much later in life.

When a baby is born, she has just about all the neurons that she'll ever have. According to the Child Welfare Information Gateway, "Brain development, or learning, is actually the process of creating, strengthening, and discarding connections among the neurons; these connections are called synapses." While a baby has roughly 100 billion neurons at birth, she is born with very few synapses between these neurons. The only synapses (along with the amount of myelin, a fatty insulation tissue that ensures clear transmission across the synapses) she does have are the most basic ones, those that dictate the most essential functions needed to simply be alive.[3] Furthermore, that baby's memory is also most basic. She is born with only her implicit memory, meaning she can perceive and recall memories via unconscious means. For example, the baby can recognize her own mother's voice. Explicit, conscious memory is developed around the age of two.[4] Perception development, on the other hand, is a much more complex process.

The Formation of Perception

David Bohm describes the development of perception in the appendix of the book The Special Theory of Relativity. Bohm writes about the research of Jean Piaget, a Swiss developmental psychologist and philosopher known for his epistemological (theory of knowledge) studies with children.

In Stage 1 of perception development, functional aspects are formed. Reflexes develop to fit different aspects of the environment. The environment is recognized by functional aspects, e.g. food to satisfy hunger.

Impulse followed by sensation is learned in Stage 2. This is the beginning of perception. Eventually there is pleasure in the reflexes that are produced. The child discovers that a pleasant sensation is achieved by doing something and she begins to recognize this. Recognition that a past event has been repeated comes first. The ability to call upon this event in the memory comes much later. At this stage there is only the knowledge that a certain impulse will lead to a certain pleasure.

Performance and coordination are then developed during Stage 3. To recognize a similarity is necessary before seeing something as permanent in the flux of process. Early on there is no realization that the object that the child sees is the same as the object that she hears, but later on she learns that there is a coordination. The child can then understand that she sees what she hears. She grasps what she sees.

Patterns are then recognized in Stage 4. There is still no notion of permanence. In the total flux of experience, she can now recognize a certain pattern. These combinations itself are experienced as totalities. The object is not recognized outside its normal context. The child finally begins to develop a perception for what isn't considered to be normal in Stage 5. When the child can follow a moving object with her eyes, she is able to recognize the invariance of its form despite its movement. She is building up the reflexes to perceive objects apart from their normal context.

By stage 6, the child learns that something can be undone by a second operation. However, she doesn't understand yet that an object exists when she doesn't see it. The child isn't yet able to see herself as separate from the world. Then the child sees the relationship between cause and effect. The child begins to recognize other people, animals, and objects as the cause of things that are happening in Stage 7.

During stage 8, coordination of visual with tactile and movement is learned. The notions of space and time are being built. When the child handles objects and moves her body, she learns to coordinate her changing visual experiences with the tactile perceptions and bodily movements. During Stage 9, the notion of permanent places and objects is developed. At this stage he discovers that he can always return to a place in many different ways. There is the notion of permanent places and permanent objects.

Stage 10 includes the beginning of memory. The child learns to call upon images from the past. There is now a difference between past and present. The child will soon be able to perceive that there is a future when she starts to form mental images of what she expects. The formation of an image of an absent object occurs during Stage 11. The child is able to form an image of an absent object.

By Stage 12 the child can form a mental image of the world, with both perceived and unperceived things. She is able to create or produce something. She is then able to distinguish herself from the world in Stage 13. Because of the ability to create a mental map of the world (the ability to imagine), she sees places that are occupied by permanent objects. One of these "objects" is herself. She can perceive other people as well, meaning a general picture of the world is formed. At this point the child finds it difficult to distinguish between what is imagined or remembered in thought and what is actually perceived through the senses.

During Stage 14, the mental map becomes reality. What we see often depends on what we know about it. We learn to see the world through a certain structure of ideas. We react immediately to each new experience before we have time to think. We may even believe that certain (other) ways of perceiving the world aren't possible when in reality our perception is what we discovered and build when we were children.

Perception is translated into language during Stage 15. This stage is about translating the perception of the structure of the world in thought and language. This is very confusing as the ideas and words often contradict what is perceived. This learning is quite gradual. Finally, during Stage 16, the need arises for logical thought. She wishes to reflect on the structure of the world and to communicate with other people. She wants to apply her ideas to a practical problem. This is an ongoing part of development that builds up knowledge and understanding of the world.[5]

From the perception of being in a state of flux and uncertainty to the structure of a mental map, the development of perception is no simple matter. Throughout the development process, the child learns about relationship. The child becomes certain of endless relationships and those relationships create a mind map—a web of knowledge. Perception boils down to learned causes and effects. As an adult, immediate perception takes on the structures of these maps. In other words, she is no longer aware that the map only represents what has previously been perceived. Think of it as a nerve impulse. When you touch a hot stove, sensory nerves send an impulse up to the brain telling you that it's hot. It hurts. Move your hand! Similarly, I experience a "reflex" when I observe certain things.

In his book The Developing Mind, Daniel Siegel defines the mind: "A core aspect of the mind is an embodied and relational process that regulates the flow of energy and information."[6] This definition helps us to understand perception, experience, and the energy that flows between them. Because of this, the mind—including perception—can be thought of as a series of processes rather than a discrete object within us. In more tangible terms, the structure within us—the brain—physically changes and behaves as a function of both experience and genetics, yet there are limitations for structural changes and tendencies within the brain in adulthood. The mind—the lens through which we see the world—however, may continue to grow beyond infancy, childhood, and adolescence. Thus experience may be considered to be objective, for one's experience of something as simple as seeing red may not be exactly the same as another's. 

The Pruning of Synapses

As a child grows up in a (nurturing) environment, her synapses are formed at an incredible rate. At the peak of cerebral cortex development, some 2 million synapses may be created each second.[2] Many of these synapses are strengthened yet many are discarded as part of the normal developmental pruning process.[1] However, that pruning process may occur in excess if the child is deprived of vital stimulation that is neglect can lead to significant loss of synapses.

The synapses that are strengthened can be thought of as snowy paths that are continually trampled upon. With each pass through the pathway, the snow becomes more packed and the pathway more pronounced. By age 3, a child's brain is about 90% of its adult size, the size and growth of the various regions depending on the amount of stimulation they receive. The frontal lobe, the area responsible for reasoning, planning, anticipating outcomes, impulse control, self-monitoring, and self-awareness, experiences a great deal of growth just before puberty. Emotional and sexual abuse can both affect this area of the brain.[7] The limbic system matures throughout adolescence. And the main stages of brain development continue until at least the mid-twenties. (Some doctors, like Dr. Nemeroff of the University of Miami, say that the brain doesn't fully develop until age 23.)

Even though by the time a child reaches the adolescence stage roughly half of her synapses have been eliminated, brain development lasts a lifetime. How else would we continue to be able to learn, remember things, and adapt to changing environments?[8] This ability to change in response to repeated stimulation is known as plasticity, and plasticity is dependent on the developmental stage and region of the brain.[9] That's why it's common for us to comment on how we wished we'd learned certain activities while we were young, because then the learning would've been much easier. Cortex plasticity lessens as one gets older, but it's forever malleable to some degree. As said by Dean Buonomano, a professor of Behavioral Neuroscience and Neurobiology and member of the Brain Research Institute at UCLA, back in 1998, "It has been clear for almost two decades that cortical representations in adult animals are not fixed entities, but rather, are dynamic and are continuously modified by experience."[10] This fact suggests that sexually abused and/or neglected children may be able to make up for their negative experiences later in life, but it might be more difficult. The key takeaway is that infant and childhood experiences dictate the growth and survival of synapses as well as various regulations within the brain.

According to the Child Welfare Information Gateway, "Our brains prepare us to expect certain experiences by forming the pathways needed to respond to those experiences." These preparations equip us and enable us to adapt to our environments. The Child Welfare Information Gateway informative issue goes on to say, "Because the brain adapts to its environment, it will adapt to a negative environment just as readily as it will adapt to a positive one."[3] There's now scientific evidence that childhood maltreatment (abuse as well as neglect) results in altered brain functioning. There's even emerging evidence that there are specific time frames throughout an individual's childhood when the child's brain is more vulnerable to certain experiences.

The authors of Helping Victims of Sexual Abuse write, "Identity formation begins in infancy…If there is a delay in a child's need being met, the child's distress increases. At this point, significant "learning" takes place: A child might learn that needs will consistently be met, needs will inconsistently be met, needs will be met with violence, needs will be neglected or ignored, and/or needs will be sexualized." When a baby's cry leads to comfort, when her tears lead to tenderness, her neural pathways are strengthened. She learns how her physical and emotional needs will be met. When those needs aren't met or they're met with wickedness, the child's brain will reflect this anticipation of harm. These babies learn an entirely different lesson. Their pathways are strengthened under negative circumstances, preparing the children to cope in a malevolent world.

For example, from Barbies to babies, I hated dolls. Never understood the point of them. I preferred the stuffed animals, for what furry friend could ever bring about such negative emotions? At a young age, I knew that playing with people would be difficult, messy. I inherently knew that they weren't nearly as good as the other little girls were making them out to be. And undressing a Barbie for fun? More like re-victimization. I could never do such a thing to her or to me.

These developed (or underdeveloped) brain structures, synapses, and explicit and implicit memories all work together to synthesize instinctive processes. Eventually the child or adult no longer has to think much at all about these happenings, for her brain has finished learning them. And if we've experienced childhood sexual abuse (CSA), we possess memories that may "adversely color our view of the world" throughout our lives. More specifically, childhood maltreatment "has been called the tobacco industry of mental health."[11] Just as smoking increases one's risk for a wide variety of physical diseases, CSA may contribute to a long list of mental illnesses. So the question is, is there any way to maintain a healthy brain or at least "regain" one in a sense?

Clearly prevention of CSA is the optimal choice. According to Mary Dozier, chairman of child development at the University of Delaware, "If we can intervene and change a child's environment, we actually see plasticity in the brain. So, we see negative changes when a child is abused, but we also see positive brain changes when the abuse ends and they are more supported. Intervention can be very effective."[12] Yet the naivety of parents may cost their little one her childhood innocence along with a great deal of her adulthood energy. Parents must be educated and careful, yet often parent are the ones at fault. In the case where abuse has already taken place, the brain has already hopped on the trajectory of damage. Early, consistent, intense intervention is ideal. Signs that a child may have been abused may include: an inability to control emotions, submissiveness, difficulties learning in school, difficulties getting along with other children, unusual sleeping or eating behaviors, attempts to provoke fights or instigate sexual experiences, unresponsiveness to affection, and emotional or social inappropriateness for her age.[3] Yet some of us still find ourselves years later on the other end of a long history of sexual abuse. Is there hope for us too?

[1] ZERO TO THREE (2009): Brain development: Frequently asked questions: Retrieved February 2014, <www.zerotothree.org>.
[2] McCollum D (2006): Child Maltreatment and Brain Development. Clinical and Health Affairs.
[3] Understanding the Effects of Maltreatment on Brain Development (2009): Child Welfare Information Gateway.
[4] Applegate JS, Shapiro JR (2005): Neurobiology for clinical social work theory and practice. Norton & Company.
[5] Bohm, David (2006): Appendix A of The Special Theory of Relativity. Routledge Classics.
[6] Siegel DJ (1999): The Developing Mind, 2nd edition. The Guilford Press.
[7] Sexual and Emotional Abuse Scar the Brain in Specific Ways (2013): Time Health & Family. <www.healthandtime.com>.
[8] Ackerman SJ (2007): The brain in adult life and normal aging—The Dana Guide. <www.dana.org>.
[9] Perry BD (2006): Applying principles of neurodevelopment to clinical work with maltreated and traumatized children: The neurosequential model of therapeutics. The Guilford Press.
[10] Buonomano DV, et al (1998)
[11] Szalavitz, Maia (2013): How Child Abuse Primes the Brain for Future Mental Illness. Time Health & Family. <www.healthandtime.com>.
[12] Schulte, Brigid (2009): New report finds that effects of child abuse and neglect, if untreated, can last a lifetime. Current Psychiatry Reports, 11(1):63-68. <washingtonpost.com>.

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