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Child Development

The Myth of the First Three Years

Personality does not become immutable after early childhood.

 Preschool Program by Seattle Parks, C.C. by 2.0
Source: Flickr: Preschool Program by Seattle Parks, C.C. by 2.0

People of any age can learn new information and change their behavioral responses to a wide variety of environmental contingencies. If that were not true, and people could not adapt to changing environments throughout their lives, it is highly unlikely that homo sapiens would have survived as a species. And yet, here we are.

The practice of psychotherapy is predicated on the view that change is possible. If people become immutable at a certain age, then how would therapy ever help them change?

However, some schools within the field seem to insist that most of our habits are completely fixed during childhood. According to the early psychoanalysts, for example, our personalities are completely developed by the time we are 5 years old. People with borderline personality disorder were thought to have “fixated” at the age of two! This meant that any psychological development after that completely stopped.

Neuroscience data is frequently cited by people without sufficient expertise in that domain. In doing so, they often make assertions based on study results that have limited applicability to the psychological phenomena under discussion, or have no basis in findings from studies. A book from 1999, The Myth of the First Three Years by John T. Bruer, describes a particular heinous example of pseudoscience that took hold with the participation of several prominent politicians and celebrities.

The idea goes something like this: the neurons in the brain continuously develop hundreds or even thousands of synaptic connections per second during interactions with attachment figures until every child reaches the maximum number of such connections — at age three. The connections then start to be pruned. This means that the number of synaptic connections decreases over time. Therefore, kids under three need to be properly stimulated. They must be read to, learn their ABC's as early as possible, attend preschools, and listen to a lot of classical music. If not, a window of opportunity will be closed forever.

This idea has led to a lot of parental guilt and anxiety, which I believe is far more damaging to kid’s psychological development than not having heard enough Mozart. Because of kin selection, we are probably more affected by the emotional state of our attachment figures than pretty much anything else.

Parents who feel they may have damaged their child by, say, putting them in the wrong daycare program may become emotional wrecks who then overindulge their children, trying to prevent them from experiencing any emotional stress. When they seem to be failing at that, as they must, they may then at times react with fury and even strike out physically with a child.

In reality, the synaptic pruning probably leads to higher brain efficiency in reacting to the environment in which the child is raised, but some people think that the loss of neural connections after age three means something else. They think that the period between ages 0-3 determines your IQ among other things, and if we want smarter and more resilient kids we must provide the proper stimulating environment or the development of our future abilities will be compromised.

It is true that some aspects of this idea may have limited applicability to some of our psychological abilities — like learning a second language without having an accent. Almost impossible to do after the age of 12-14. But to think that somehow all of our abilities are like that is just wrong.

What may get fixed in the first three years is that children become permanently much more responsive to their attachment figures than to anything else. The “serve and return” process described in this post is probably related to this. Most neuronal tracts in brain are plastic in that they can form, or become stronger or weaker, over one’s entire lifetime. However, certain nerve tracts in the limbic system that are conditioned by one’s environment to respond with fear are highly resistant to major alterations. In addition, certain faces — faces of kin — may trigger and reinforce a lot of automatic social responses to different people and situations.

The idea that children who are exposed to one environmental event or another develop immutable brain changes has even affected highly important research in adverse childhood experiences like child abuse. Researchers do brain scans of abuse victims as adults and compare them to control subjects who had more loving childhoods, and differences in the size and activity of certain tracts remain. Hence, these researchers state, these brain changes are now irreversible.

Well, they may be, but we still don’t really know. I kind of doubt it. There is some limited evidence that some of the changes can modulate with therapy, as described in a recent article in the German journal Nervenarzt (November 2018) by Schmahl et. al. Their conclusion:

Although the overall database is still sparse, clinical improvement in psychotherapy appears to be associated with modulation of brain structure and function. Frontolimbic regulation circuits including the amygdala, insula, anterior cingulate cortex (ACC) and other prefrontal areas appear to be involved in these changes. An important finding is the reduction of initially increased amygdala activity after successful Dialectical Behavior Therapy.

Some researchers seem to think that, because subjects are no longer being actually beaten or molested, that the involved brain tracks are no longer being strengthened through environmental reinforcement. That must also mean that continued negative interactions with the attachment figures have come to a complete stop. Nonsense. These children continue to be around them throughout their lives, or in some cases do cut them off, but hear about them through other relatives. The “different” brain structures are thusly maintained. If that reinforcement were to be corrected, maybe those tracts would start to revert back to the size and activity levels seen in the control subjects.

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