Tag Archives: genetic determination

Nature or Nurture: The relevance of psychological intervention

In the last post, we discussed the importance of nature, i.e., our genetical background, in the rapidly developing science of behavioral genetics, and the realization that much of what was attributed to parental influences is genetically determined, or at least co-determined. This post discusses why psychological intervention (as an aspect of nurturing) is still very much relevant in today’s world, genetics not withstanding.

This is the second guest post from Prof. Dov R. Aleksandrowicz, MD, former President of the Israeli Psychoanalytic Society, and a Training and Supervising analyst at the Israel Institute.

Writing an obituary to psychological intervention would be greatly premature, to say the least. Firstly, genetic factors are highly significant and have been underestimated by many, but they are not immutable verdicts, like the intention of gods in some Greek tragedy. Genetics teaches us that genes can be activated or turned-off, either by other, regulatory genes, or by environmental influences. The study of such influences, i.e., the science of epigenetics, is one of the hottest topics in genetic research and more than one possible mechanism seems to be involved.

Secondly, there are some well-conducted studies demonstrating the effectiveness of therapeutic intervention. Demonstrating scientifically the effectiveness of an intervention is a difficult challenge, but it has been done. Shorter psychological treatments, such as cognitive-behavioral therapy, have proved to reverse neurotic brain functioning patterns concomitant with neurosis, as effectively as medication. The therapeutic benefits of longer, more complex therapies, such as psychoanalysis, are much more difficult to prove scientifically, but some such studies have been successful.

The third, and perhaps most significant evidence of the critical importance of child-rearing and of psychological intervention comes, paradoxically, from neuroscience itself. Modern neuroscience demonstrated that the classic distinction between “structural” and “functional” disorders is an illusion. In classic psychiatry we were taught that Alzheimer dementia is caused by loss of neural tissue, an irreversible, “structural” change. Depression is presumably caused by some chemical, transient, hence transient, imbalance, and is therefore “functional”. Hysteria, or conversion neurosis, is due to unfavorable childhood experiences and therefore also “functional”. So is schizophrenia, since no abnormalities could be found at autopsy in the brains of the patients.

To-day we know that not all damage to the brain causes irreversible changes in behavior, such as Alzheimer disease does. The brain, especially the young, developing brain, can develop amazing compensatory mechanisms for an impaired function. The ability of our brain to grow new nerve cells is very limited, but its ability to develop new connections (synapses) is practically unlimited. At the same time we know now that there is no change in function without some change in structure, although on a microscopic or molecular level. Some of those changes are reversible and transient, but others can be quite resistant to change.

The human brain is an amazing organ, a “self organizing system”. Its function is to absorb stimuli from the environment and direct the organism to respond in an adaptive way, including in many cases influencing the environment in a way favorable to the organism. No wonder, therefore, that a brain actively shapes itself under the influence of environmental stimuli and of experience. The eagerness of the brain to absorb the environment can be seen in the intense curiosity of the infant staring at its surroundings.

Man, like all mammals, depends on learning in order to adapt and survive. The prolonged development from birth to maturity, dictated by the biological need to reach adult size (no mammal can be born having the size of an adult) proved itself a perfect opportunity to acquire learned as opposed to instinctual behavior, an excellent adaptive tool. Learning, cognitive as well as emotional, is a microscopic structural change in the brain tissue, as demonstrated by the Nobel Prize winner Eric Kandell and by others.

Moreover, the brain of social animals, including Man, is pre-programmed to respond in a special way to other subjects. The unique emotional and cognitive bond that develops between an infant and his caregiver cannot be duplicated by the most sophisticated apparatus. Likewise, the emotional and cognitive process which takes place between a therapist and a patient or a teacher and her pupils, cannot be duplicated by a computer program and will not re-created by chemical means for many years to come, if ever.

The brain is the primary learning organ, but not the exclusive one. The immune system’s role is to learn to recognize (chemical) friend from foe. We know very little about how other tissues “learn” from the environment, but the ability to change a response as a result of experience is a very old quality of living organisms, probably nearly as old as life itself. We may justifiably assume that the body, as a whole, learns.

In conclusion, modern science teaches us that nature and nurture are not opposed but inextricable. Our brains shape the way we experience and the way we influence our environment and our environment shapes our brains. We are born to interact with other people, our nature is to nurture and be nurtured.