首页
登录
职称英语
One fact was clearly demonstrated by the early sleep researchers: one part o
One fact was clearly demonstrated by the early sleep researchers: one part o
游客
2023-09-03
14
管理
问题
One fact was clearly demonstrated by the early sleep researchers: one part of the night is not just like another. As scientists began to compare the records of volunteers during the 1950’s, they observed that human sleep follows a rhythmic schedule. They noted that not only was this schedule much the same in healthy persons of the same age with similar habits but, from night to night each individual had an EEG (电脑图) record almost as consistent as a signature.
Sleep and wadefulness, once considered to be the light and dard of consciousness, no longer seem to differ so sharply. To sleep does not mean to drown in an ocean of darkness. Actually, sleep is not a unitary (单一的) state; it involves many shades or detrees of detachment from the surrounding world. While sleep may feel like a blander of darkness punctuated by dreams-a time when the mind is asleep nothing could be less true. All night long a person drifts down and up through different levels of consciousness, as if on waves. With laboratory methods, researchers have been able to chart the typical stages of the journey into sleep.
The journey starts while the subject is still awake but beginning to relax. His brain waves, which have been low, rapid, and irregular, begin to show a new patten. This new pattern, which is known as alpha rhythm, is an even electrical pulsation (震动) of about nine to 12 cycles per second. Most people do not know what the alpha state feels like, but during the last few years researchers have been able to teach subjects how to recognize and control their alpha rhythm.
When their EEG shows an alpha rhythm, the subjects are notified, either by a sound or by the appearance of a color on a screen. Because the alpha state tends to be pleasant and relaxed, the ability to sustain it can help tense people ease their passage into sleep. A moment of tension, a loud noise, an attempt to solve a problem, however, and the alpha rhythm may vanish.
As the subject passes throuhg the gates of the unconscious, his alpha waves grow smaller, and his eyes roll very slowly. For a moment, he may wake up during this early part of the descent, alerted by a sudden spasm that causes his body to jerk. Like the brain waves, this spasm (痉挛) is a sign of neural changes within. Known as the myoclonic jerk (肌痉挛), it is caused by a brief burst of activity in the brain. Although it is related to epileptic (癫痫) seizures, the myoclonic jerk is normal in all human sleep. It is gone in a fraction of a second, after which descent continues. The subject has not felt the peculiar transformation, but now he is said to be truly aleep. [br] According to the author, the alpha state has been shown to be ______.
选项
A、unmeasurable
B、a brief burst of activity in the brain
C、unpleasant for some people
D、comtrollable
答案
D
解析
文章第三段谈到,近年来;研究人员已经能够教给实验对象辨认和控制这种alpha rhythm的方法。A项不正确,是因为其节奏为about nine to 12 cycles per second,B项和C项都不正确,是因为The alpha state tends to be pleasant 且 Most people don’t know what the alpha rhythm feels like.
转载请注明原文地址:https://tihaiku.com/zcyy/2983075.html
相关试题推荐
Whatifwecouldreadthemindofaterrorist?ResearchersatNorthwesternU
Whatifwecouldreadthemindofaterrorist?ResearchersatNorthwesternU
Whatifwecouldreadthemindofaterrorist?ResearchersatNorthwesternU
Whatifwecouldreadthemindofaterrorist?ResearchersatNorthwesternU
ResearchersattheUniversityofCalifornia-Berkeleyarechallengingourlon
ResearchersattheUniversityofCalifornia-Berkeleyarechallengingourlon
ResearchersattheUniversityofCalifornia-Berkeleyarechallengingourlon
ResearchersattheUniversityofCalifornia-Berkeleyarechallengingourlon
Researchershavediscoveredthatspendingafewminutesthinkingaboutyour
Researchershavediscoveredthatspendingafewminutesthinkingaboutyour
随机试题
Althoughgeneticmutationsinbacteriaandvirusescanleadtoepidemics,so
"Youwouldratherfollowthanlead"means______.[br]Ifoneenjoyslife,onei
九寨沟风景名胜区位于中国西部四川省阿坝藏族羌族自治州(AutonomousPrefecture)九寨沟县南坪镇。全区面积约720平方公里,大部分为森林
交变盐雾试验是一种综合盐雾试验,它主要用于()。A.空腔型的整机产品 B.线
胆囊结石的病因病理不包括()A.肝脏损伤 B.代谢因素 C.胆道异
红利支付导致公司借款需求的原因在于()。A.公司利润收入在红利支付与其他方
(2019年真题)根据《行政强制法》规定,下列有关冻结的说法中,正确的是
C
A. B. C. D.a=0
钢筋原材料进场检验项目中,预应力钢丝的检验项目有()。A.外观检查 B.拉力、
最新回复
(
0
)