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CBT is a "top-down" approach based on the idea that if a person thinks right, they will feel alright. Brain scan research suggests otherwise. Arousal and emotional regulation are structured like an iceberg. Most regulation takes place outside of consciousness. Cognition accounts for a minor part of our regulation.
Researcher Joseph LeDoux says a great deal of emotional regulation takes place bottom-up. "Emotions can be and, in fact, probably are mostly processed at an unconscious level. We become conscious and aware of all this after the fact."
Research by Stephen Porges shows that in social situations people are up-regulated by stress hormoness, and are down-regulated by signals that are sent, received, and processed unconsciously. He terms the reception of social signals neuroception - rather than perception - to emphasize the unconscious nature of this activity.
When we encounter a stranger, the amygdala releases stress hormones. These hormones activate a primitive system, the Mobilization System, which produces an urge to escape. Simultaneously, the hormones activate a sophisticated system, Executive Function. If operating well, Executive Function contains the urge to escape and consciously assess the situation to determine whether the stranger's presence is a threat, offers an opportunity of some sort, or is of no consequence at all.
While Executive Function is making its conscious assessment, another sophisticated system comes into play unconsciously. Porges calls it the Social Engagement System. This system unconsciously processes the signals the stranger is unconsciously sending. If these signals indicate trustworthiness, the Social Engagement System applies the "Vagal Brake," neurological stimulation of the vagus nerve, that slows the heart and causes the parasympathetic nervous system to reduce arousal.
Imagine you have been invited to a party and are looking forward to it. When the day arrives, you go to the location. You walk in expecting to be greeted by the host. Instead, you see people you don't know. Reacting to the unfamiliar faces, the amygdala releases stress hormones. Though you have been looking forward to this event, you suddenly wish you were home! That "tip of the iceberg" desire is being caused below the surface by your Mobilization System, a "one trick pony" that urges escape whenever the amygdala releases stress hormones.
Though you could get immediate relief by leaving, Executive Function offers another option. If you find someone to talk with and the conversation goes well, the desire to be home will disappear. A few minutes later you are talking with someone who is attuned to you. The signals being received by your Social Engagement System indicate benign intent. Meanwhile, the amygdala - still regarding the person as a stranger - continues releasing stress hormones. Ordinarily, these hormones would rev your heart rate up to 100 beats per minute. But since your Social Engagement System reads this person as safe, it stimulates the Vagal Brake, which slows your heart rate down to a normal 70 beats per minute.
Your Social Engagement System has another way to calm you. In certain situations, through the release of the anti-anxiety hormone oxytocin, it shuts down your fear system. Oxytocin inhibits the amygdala, temporarily preventing the release of stress hormones.
Why would the brain shut down the fear system? Nothing is more important in biology than reproduction. Inhibition of the amygdala facilitates mating with a person who is genetically dissimilar. If, as you continue to talk with this person, sexual signals begin to be passed back and forth, chemistry happens. Oxytocin is produced which inhibits the amygdala. Stress hormone release ends. Feelings of fear disappear. If desire is present, fear does not stand in the way of desire being acted upon.
Oxytocin puts a hormonal "do not disturb" sign at the door of your mind. It is produced when lovers gaze romantically into each others eyes, during foreplay, and in the afterglow of sexual activity. Oxytocin is also produced when nursing of an infant. It allows the mother to spend extended time nourishing the child instead of becoming concerned about other matters.
Phobia can be treated by linking each identifiable trigger in an anxiety-producing situation to a vividly recalled memory that activates the Vagal Brake or causes the release of oxytocin. In the SOAR fear of flying program, clients gain the ability to regulate their fears and anxieties about flying by linking each moment of flight to the memory of an experience that, when recalled, regulates arousal. When links to the anxiety-producing stimulus cause Vagal Brake activation, or oxytocin production, anxiety is controlled unconsciously; which is to say, "bottom-up."
