2017年4月15日托福阅读真题+题目+答案：Cerebral Lateralization

2017年4月15日托福阅读真题+题目+答案：Cerebral Lateralization

The highest brain center in humans, the cerebrum, consists of two halves (or hemispheres) connected by a band of fibers called the corpus callosum. Although identical in appearance, the left and the right cerebral hemispheres serve different functions and control different areas of the body. The left cerebral hemisphere controls the right side of the body, and it contains centers for speech, hearing, verb al memory, decision making, and processing of language, to name a few. By contrast, the right cerebral hemisphere controls the left side of the body and contains centers for tactile (touch) sensations, music, and emotional expressions. Thus, the brain is a lateralized organ. Cerebral lateralization also involves a preference for using one hand or one side of the body more than the other. About 90 percent of adults rely on their right hand (or left hemisphere) to write, eat, and perform other motor functions (involving movement), whereas these activities are controlled by the right hemisphere among those who are left-handed. However, the fact that the brain is a lateralized organ does not mean that each hemisphere is totally independent of the other, for the corpus callosum, which connects the hemispheres, plays an important role in integrating their respective functions.

1. The word “integrating” in the passage is closest in meaning to

A) adjusting

B) determining

C) coordinating

D) performing

2. According to paragraph 1, why is the cerebrum considered a lateralized organ?

A) Its halves are connected by a band of fibers called the corpus callosum.

B) Each hemisphere of the brain is totally independent of the other.

C) Different sides of the brain are responsible for different functions.

D) It creates a preference for using one side of the body more than the other.

3. According to paragraph 1, which of the following is true of the corpus callosum?

A) It controls both sides of the body.

B) It connects the two hemispheres of the cerebrum.

C) It determines which side of the body is preferred.

D) It allows each hemisphere to operate independently of the other.

When do the two cerebral hemispheres being to “divide the work” and become lateralized? It was once thought that lateralization took place gradually throughout childhood and was not complete until adolescence. Now, however, it is believed that brain lateralization may originate in the prenatal period (before birth) and is clearly evidence at birth. For example, it has been noted that about two-thirds of all fetuses end up positioned in the womb with their right ear facing outward, and it is believed that this gives them a right-ear advantage and illustrates the left hemisphere’s specialization in language processing. From the first day of life, speech sounds stimulate more electrical activity in the left side of the cerebral cortex than in the right. ▉ In addition, most newborns turn to the right rather than to the left when they lie on their back, and these same babies later tend to reach for objects with their right hand. ▉ So it seems that the two cerebral hemispheres may be biologically programmed to assume different functions and have already begun to “divide the labor” by the time a baby is born. ▉

4. The word “assume” in the passage is closest in meaning to

A) prefer

B) take on

C) recognize

D) separate

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2017年4月15日托福阅读真题+题目+答案：Cerebral Lateralization，10元有偿！