The Mystery Known as Depression, Part 3/12

3. THE THREE LEVELS OF CONSCIOUSNESS

To understand how it is possible to trace the causes of a lifelong illness – and its cure – to the very beginning of a person’s life, I must explain my view of the three levels of consciousness.
We basically have three brains in one as MacLean (1985, 1990) already proposed in 1960s: the brainstem, the limbic system, and the neocortex, each representing different stages of evolution, from shark, chimp to human brain, respectively. These neurologic stages of brain growth correspond to three distinct levels of consciousness: the earliest, pre-verbal stage of infancy, followed by childhood and finally present-day awareness. At each level of brain development, we have specific needs that must be fulfilled uniquely. The earlier the needs the more lasting the consequences when they are not fulfilled, and the more grave the imprint. In infancy, we have a need to be touched and nurtured tenderly. On the second line, we seek fulfillment of emotional needs: to be listened to, to feel secure and supported, to get an empathetic response to our hurts and fears. And the third level involves intellectual stimulation, communication and understanding by the parents. Fulfillment on this level can lead to clear and logical thinking; to an accuracy of perceptions.

3.1. First Line – The Brainstem
The first level, the brainstem, is a primitive or reptilian brain, which is our oldest brain system (MacLean, 1990). The brainstem was the first to evolve, and the first part of the central nervous system to develop in human evolution. It seems that we never lost that part. We just added new brain tissue on top of it. The brainstem deals with instincts, basic needs, survival functions, sleep, and basic processes that keep us alive such as body temperature, blood pressure, heart rate and very deep breathing. At this level, we can store a carrying mother’s depression, anxiety, stress, drug-taking, smoking, or drinking. Mother can also communicate, through her changing hormones, her unconscious rejection of her coming baby, which then becomes stored in the baby’s brainstem. Such experience is not stored as ideas, obviously, since we don’t yet have a neocortex, the thinking, intellectual, comprehending mind. But what is important is that the imprints in this storehouse will later motivate certain thoughts and aberrations of thinking. The brainstem imprints the deepest levels of pain because it is developed during gestation and handles life-and-death matters before we see the light of day.

3.2. Second Line: The Limbic/Feeling System
The second level of consciousness is basically the limbic system of the brain (and its affiliates), which is responsible for feelings and their memory (MacLean, 1990). It provides images and artistic output, processes certain aspects of sexuality, and is partly responsible for anger and fear. The limbic system possesses some key structures which affect brain function. They are the hypothalamus and thalamus; the hippocampus, which is the guardian of emotional memory; and the amygdala.
The hippocampus contains the archives of early experience, particularly trauma, and also puts a damper on amygdala activation so that our reactions themselves do not become a danger; after all, continually high blood pressure and heart rate will threaten our existence. The hippocampus has a high density of stress hormone receptors and is therefore quite sensitive to stress. The context of a feeling is predominantly organized by the hippocampus. It gives us an anchor for our feelings—a time and place—and allows us to connect to our feelings.

The amygdala is one of the most ancient structures of the brain and the oldest structure of the limbic system. It is the hub of the emotional system; the gateway to feelings. It gives us the sensation behind feeling, while the later developing hippocampus registers those feelings as facts. Early traumatic memory is consolidated by the amygdala. Luckily, when the going gets rough, it can help manufacture its own opium to hold back pain. In this way it helps us remain unconscious. It is truly a wonder that this small brain structure “knows” when to stop pain and can release a poppy derivative to help. More, it tells other brain structures about how much to release and when to stop.

The hypothalamus works with the lower structure, the pituitary, to govern the release of key hormones, not the least of which are the stress hormones. When we have strong emotions, it is the hypothalamus that organizes our response. (Within the hypothalamus lie two different kinds of nervous systems, the sympathetic and parasympathetic, which are key to understanding depression and are discussed in detail below.)

The thalamus is the central switchboard of the brain, relaying certain aspects of feeling to the frontal cortex. It can decide a feeling is too powerful to be felt and orders that the message not be relayed, and thus kept from awareness. The thalamus talks straight neurochemical talk, a language that expresses itself wordlessly. Yet it can translate painful messages into something understandable by the frontal cortex. If the pain is too much, the message that arrives is garbled. If it is acceptable, the gates open and the message is clearly understood – we know what we feel.

3.3. The Third Line: The Neocortex
The third line is the neocortex, the part of our brain that was the last to evolve and the one responsible for intellectual functioning, generating ideas and thinking (MacLean, 1990). The left pre-frontal area deals with the external world, helps us repress and, when able, to integrate feelings. It comes online at about the third year of life. The frontal cortex is part of the feeling system to the degree that it gives meaning and understanding to our physiologic- emotional reactions. The neocortex serves as a portal for entry into the suffering component of memory, a portal that cannot operate by itself. It’s the first door we walk through toward retracing our history and understanding our pain.

We can be fulfilled or deprived on any of these levels; when deprivation occurs so does pain, as the lack of fulfillment means that the integrity of the system is threatened. And pain is most often accompanied by its counterpart, repression. Fulfillment is more serious and urgent as we descend down the neuraxis on what I call the chain-of-pain. Indeed our biology dictates that deep pain elicits strong repression, to keep the pain at manageable levels. Heavy repression on the first line can mean a deadness of affect, a lack of good interconnection to bodily function so that sex is problematic and appetite is dulled; there is a lack of energy and passion. Symptoms on the first line include ulcers, colitis, and breathing problems. Symptoms on higher levels have different manifestations; the inability to make a decision, to be independent and forthright and to be aggressive.

This is simply a brief overview of the three levels in order to better understand the origins of depression and its therapy. If we consider that those ancient brains are still active in our head, the nature of the problem becomes clearer. All three brains should work in harmony throughout our lives. How they all get along is paramount. We need clear channels among the levels; otherwise there is distortion. Early trauma, however, creates a lifelong disharmony and disconnection among brain levels, resulting in many forms of mental illness. Essentially, neurosis is driven by lower brain centers that are trying to communicate to higher ones but are unable because a disconnection has occurred, a disconnection caused by the imprint of an early lack of love that spells hopelessness and helplessness. The goal of therapy is to restore that harmony, neurologically and psychologically, because consciousness (not to be confused with awareness) means all three levels working fluidly.