When sensory information comes into the brain, it passes through two parallel systems. The first of these is a sensory screening system which allows the Prefrontal Cortex (PFC)—the brain’s Executive Center—to determine what is important to be processed and what should be screened out. Without this, our world is chaotic (as, for example, in the case of someone with Autism), with no distinction between information and noise.
At the same time, another system evaluates the same data with a very different focus. On either side of the brain, inside the temporal lobes, is a structure called the amygdala. These two fear and rage centers of the brain’s emotional system also act as its smoke alarm. We don’t really care if they give occasional false alarms as long as they never miss a real one. The amygdala receives sensory information much more quickly than the sensory screening system. Its job is simply to determine if there may be great risk or great opportunity in the information it’s receiving.
The Smoke Alarm
The amygdala can activate the Sympathetic Nervous System (SNS) and produce an immediate fight-or-flight response. It triggers the hypothalamus to stimulate a rush of adrenaline, which drives all the body’s defenses. This system switches on the SNS without any input from the PFC. It’s much more primitive and immediate in its response.
Once the SNS has been activated, the attention of the sensory screening system is drawn to the stimulus that triggered the response. The PFC quickly gathers more information to evaluate whether there is in fact a real threat or opportunity. If it decides the smoke alarm sounded in error, the PFC can turn off the response.
From an survival point of view, it is more useful to have the system turn on in error than to miss a target. It is safer to call a stick a snake than to mistake a snake for a stick.
However, if the amygdala becomes overly sensitized, it can literally fire almost constantly. This can happen when a person is highly stressed or traumatized, so he sees danger all around him. The result is that the body spends too much time in sympathetic mode, and too much of the PFC’s energy goes toward evaluating false threats and turning off the SMS.
As a brain becomes habituated to the stress response, the level of Tone in the ANS increases. There are both physical and emotional effects. As we mentioned previously, a physical stress response can trigger emotional anxiety, and vice versa. High levels of stress, which we will discuss in the next section, result in breakdowns in the body’s maintenance functions. Over time, as the level of Tone increases, rebound effects such as panic attacks or migraines can begin to occur. This high-level of emotional activation begins to feed upon itself, producing free-floating anxiety. Anxiety no longer is a “state” which is experience based on external triggers. It becomes a “trait”, which is central to our experience of life. We need not even know what we’re anxious about. This type of anxiety can be experienced either emotionally or physically.
High levels of ANS Tone are very energy-intensive. The brain and body use tremendous amounts of resources for little positive effect. This drain occurs at the very time when physiological maintenance is limited by the inability to sustain the PSNS mode. The result is physical and emotional exhaustion. The individual feels tired, without resources, hopeless and helpless in her experience of life. We call this depression.
In the training section of this book we’ll talk about the three-pronged approach to high Tone problems. First we must learn to normalize our stress response. Second, we must help our brains to regain comfort at a more reasonable level of PSNS mode. There are a variety of techniques, including peripheral biofeedback, meditation, yoga, prayer and others to assist with this process. However, none of these produces a reset. They must be used constantly as long as nothing is done to change the activation patterns in the brain which underlie and support high levels of Tone.
High Tone states are so draining, they result in symptoms that many people find more acceptable than their levels of uncontrolled emotional drive. Problems of attention and memory—even physical symptoms with sleep, elimination or migraines are seen as things happening to us from the outside, and thus less intimate than feelings of fear or depression. Even defenses our brains may adopt to deal with emotional drive, such as obsessions or compulsions are out of our control. But the reality of brain training is that all of these things are likely layers of symptoms related to our inability to deal with the stress and trauma that lie at the base of them all and are encoded in the stable habits of activation in our brains. It is there that training must begin.