請依下文回答第 16 題至第 20 題: I kept coming across “the vagus nerve” in relation to deep breathing and mental calmness: in the newbook Yang Sheng: The Art of Chinese Self-Healing, a Harvard Health blog post, and many other recentpublications. It sounded as if we had something like a secret piano key, under our skin, to press internally tocalm us down. In reality, the vagus nerve is not a single inner cord, stretching from the head to the stomach; it is asquiggly, shaggy, branching nerve connecting most of the major organs between the brain and colon, like asystem of roots or cables. It is the longest nerve in the body, and technically it comes as a pair of two vagusnerves, one for the right side of the body and one for the left. It’s called “vagus” because it wanders, like avagrant, among the organs. The vagus nerve has been described as “largely responsible for the mind-bodyconnection,” for its role as a mediator between thinking and feeling, and I’m tempted to think of it as somethinglike a physical manifestation of the soul. “Stimulating the vagus nerve to the heart has a really powerful effect on slowing the heart rate,” said LucyNorcliffe-Kaufmann, associate professor of neurology at NYU-Langone. And this, specifically, is what relaxesus. The vagus nerve is basically listening to the way we breathe, and it sends the brain and the heart whatevermessage our breath indicates. Breathing slowly, for instance, reduces the oxygen demands of the heart muscle,and our heart rate drops. I was surprised by the idea that it’s specifically the exhale that triggers the relaxation response, butNorcliffe-Kaufmann confirmed: “Vagal activity is highest, and heart rate lowest, when you’re exhaling.” Shementioned that the ideal, most calming way to breathe is six times a minute: five seconds in, five seconds out.She also noted that in the study that determined this rate, researchers found that this style of slow breathing isalso what practitioners naturally lapse into during meditation with mantras, and during the Ave Maria prayerwith rosaries. “Each time you do either the rosary prayer or a meditation mantra,” Norcliffe-Kaufmann said,“it naturally synchronizes your breathing at six times per minute.” Some other practices believed to improvevagal tone include laughing, singing, humming, yoga, acupuncture, and splashing the face with cold water —or having a full-body cold rinse. “If you’re in a stressful situation,” Norcliffe-Kaufmann said, “and when you’re like, How do I respond,how do I respond? — Just consciously slow down your breathing for one minute, or even a few seconds, youcan put yourself in a calmer state, and be able to better communicate.” 【題組】20 According to the passage, which of the following statements is true?
(A) The vagus nerve is a single inner cord, stretching from the head to the stomach. (B) Stimulating the vagus nerve to the heart has a really powerful effect on raising the heart rate. (C) Breathing slowly reduces the oxygen demands of the heart muscle, and our heart rate drops. (D) The vagus nerve contributes little to the mind-body connection.