Rewire Your Brain: Think Your Way to a Better Life
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Fight-or-Flight Response
Relaxation Response ↑ Heart rate ↓ Heart rate ↑ Blood pressure ↓ Blood pressure c02.indd 36 c02.indd 36 1/29/10 10:09:55 AM 1/29/10 10:09:55 AM Ta m i n g Yo u r A myg d a l a 37 ↑ Metabolism ↓ Metabolism ↑ Muscle tension ↓ Muscle tension ↑ Breathing rate ↓ Breathing rate ↑ Mental arousal ↓ Mental arousal The principle of taking action that I described earlier acti vates the BNST and the left PFC. This effort paves the way for the parasympa- thetic nervous system to calm you down later. The quick shift from the sympathetic to the parasympathetic ner- vous system through the actions of the PFC and the hippocampus might not occur as quickly if you suffer from PTSD. The amygdala is highly sensitized to the context of the trauma you endured. Earlier we cited the example of a war veteran who is startled by fi reworks. Yet even war veterans with PTSD can tame their amygdalas, as I have described in my book (with Dr. Victoria Beckner) Conquering Posttraumatic Stress Disorder. Different breathing patterns promote different emotional states. Your breathing rate speeds up when you are experiencing anxiety. The muscles in your abdomen tighten up and your chest cavity becomes constricted when you breathe too fast. If you tend to breathe very quickly, you may be like some people who come to my anxiety class: They have a tendency to talk very fast, and they don ’ t give themselves a chance to breathe. As they go from one sentence to another, they stir up anxiety in themselves. The neutral topic that they began talking about is lost because of their fast breathing and their anxiety. The increase in their anxiety stimulates memories and reaction patterns that are connected to the same neural networks that promote anxious thinking. Soon the new topic becomes laced with more anxiety and worries. Most people breathe nine to sixteen breaths per minute at rest. Panic attacks often involve as many as twenty - seven breaths per minute. When your breathing is accelerating, you can experience many of the symptoms associated with a panic attack, including numbness, tingling, dry mouth, and light - headedness. Since the cardiovascular system includes both the respiratory system and the circulatory system, rapid breathing will make your c02.indd 37 c02.indd 37 1/29/10 10:09:55 AM 1/29/10 10:09:55 AM 38 Rew i r e Yo u r B r a i n heart rate speed up and can make you more anxious. If you slow your breathing down, your heart rate will slow down and you will become more relaxed. To learn to relax, you ’ ll have to make an effort to develop some new habits, such as the way you breathe. Since one of the most common symptoms of panic is shortness of breath, you ’ ll have to learn to breathe differently. Actual physiological changes occur in your brain and body during hyperventilation, or breathing too fast. When you hyperventilate, you inhale too much oxygen, which decreases the carbon dioxide level in your bloodstream. Carbon dioxide helps to maintain the critical acid base (the pH level) in your blood. When you lower your pH level, your nerve cells become more excitable, and you may feel anxious. If you associate the feelings with uncontrollable anxiety, this can even spur a panic attack. The excessive dissipation of carbon dioxide leads to a condition called hypocapnic alkalosis , which makes your blood more alkaline and less acidic. Soon you ’ ll have a vascular constriction, which results in less blood reaching your tissues. Oxygen binds tightly to hemoglobin, which results in less oxygen being released to the tissues and the extremities. The paradox is that even though you inhaled too much oxygen, less is available to your tissues. Hypocapnic alkalosis leads to dizziness, light - headedness, cerebral vasoconstriction (which leads to feelings of unreality), and periph- eral vasoconstriction (which leads to tingling in your extremities). If you ’ re prone to panic attacks, you tend to overrespond to these physi- ological sensations and to breathe even more quickly. Challenging the Paradox A paradox occurs when you avoid what you fear, because your fear then grows. This is counterintuitive, because when you avoid what you fear for a short time, your fear does decrease. Over a lon- ger period, however, avoidance allows the anxiety to fl ourish. For example, let ’ s say that you are anxious about going to a dinner party because you fear talking to strangers. For a brief time, avoiding the c02.indd 38 c02.indd 38 1/29/10 10:09:56 AM 1/29/10 10:09:56 AM Ta m i n g Yo u r A myg d a l a 39 evening enables your anxiety to lessen. However, if you avoid the next dinner party invitation, and then the next and the next, you have created a problem. Because of your avoidance of those dinner Yüklə 1,07 Mb. Dostları ilə paylaş:
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