首页
登录
职称英语
THE SENSE OF SMELL1 Smell is the most direct of all the sens
THE SENSE OF SMELL1 Smell is the most direct of all the sens
游客
2024-01-04
10
管理
问题
THE SENSE OF SMELL
1 Smell is the most direct of all the senses. It is thought to be the oldest sense in terms of human evolution, which may explain why smell is
hard-wired
into the brain. The olfactory nerve, which manages the perception of smells, is essentially an extension of the brain. The olfactory nerve provides a direct link from receptors at the top of the nose to the portion of the brain that controls memory, emotion, and behavior.
2 The olfactory system
detects
certain airborne chemicals that enter the nose and then transmits this chemical information to the limbic system in the brain. The olfactory region at the upper end of each nostril is yellow, moist, and full of fatty substances. The shade of yellow indicates the strength of the sense of smell: the deeper the shade, the keener and more acute it is. Animals have a very strong sense of smell, so their olfactory regions are dark yellow to reddish brown, while those of humans are light yellow.
3 When an odorous substance enters the nose, it binds to olfactory receptor cells, the neurons lining the yellow upper portion of the nasal cavity. Olfactory receptor cells contain microscopic hairs called cilia that extend into the layer of mucus coating the inside of the nose. Odor molecules diffuse into this region and are absorbed by the cilia of the olfactory receptor cells. What this means is that when we hold a rose to our nose and inhale, odor molecules float up into the nasal cavity, where they are absorbed by five million olfactory receptor cells. The receptor cells alert the olfactory nerve, which sends impulses to the brain’s olfactory bulb, or smell center. Thus, olfactory information about the rose enters the brain’s limbic system, where, in most of us, it stimulates a feeling of pleasure.
4 The limbic system of the brain
integrates
memory, emotion, and behavior. The system is composed of a group of related nervous system structures that are the functional center of emotions such as anger, fear, pleasure, and sadness. The components of the limbic system are linked to the cerebral cortex, the part of the brain involved in complex learning, reasoning, and personality. The cerebral cortex makes decisions about the emotional content of these unique human qualities after "consulting" the limbic system and other brain centers in processing and retrieving memories. It may, in turn, use memories to modify behavior.
5 Scent may be the strongest trigger of memory and emotions. When we inhale a scent, receptors in the brain’s limbic center compare the odor entering our nose to odors stored in our memory. Along the way, memories associated with those odors are stimulated. A smell can be overwhelmingly nostalgic because it triggers powerful images and emotions. The waxy fragrance of
crayons
can instantly transport us to our second-grade classroom, or the scent of
freshly mown grass
can flood us with the joy of summer freedom.
What we see and hear may fade quickly in short-term memory, but what we smell is sent directly to long-term memory.
6 Smells can increase alertness and stimulate learning and retention. In one study, children memorized a word list, which was presented both with and without accompanying scents. The children recalled words on the list more easily and with higher accuracy when the list was given with scents than without, showing the link between smell and the ability to retain information. In another study, researchers examined how various smells can increase alertness and decrease stress. They found that the scent of lavender could wake up the metabolism and make people more alert. They also found that the smell of spiced apples could reduce blood pressure and avert a panic attack in people under stress.
Glossary:
nostalgic: causing a desire for things, persons, or situations of the past; causing homesickness
retention: the act of retaining; keeping, holding, or maintaining [br] Why does the author use the term hard-wired in describing the sense of smell and the brain?
选项
A、To describe the texture and feel of the olfactory nerve
B、To emphasize the close connection between smell and the brain
C、To compare the power of smell with that of other senses
D、To explain how the sense of smell evolved in early humans
答案
B
解析
The author’s purpose is to emphasize the close connection between smell and the brain. Clues: Smell is the most direct of all the senses; The olfactory nerve, which manages the perception of smells, is essentially an extension of the brain; ...a direct link from receptors at the top of the nose to the portion of the brain....(1.6)
转载请注明原文地址:https://tihaiku.com/zcyy/3333460.html
相关试题推荐
Youcanhave______paiddirectfromyouraccount.[br][originaltext]Presente
Youcanhave______paiddirectfromyouraccount.[br][originaltext]Presente
Youcanhave______paiddirectfromyouraccount.[br][originaltext]Presente
Youcanhave______paiddirectfromyouraccount.[br][originaltext]Presente
Youcanhave______paiddirectfromyouraccount.[br][originaltext]Presente
Listentothedirectionsandmatchtheplacesinquestions11-15totheappropri
Listentothedirectionsandmatchtheplacesinquestions11-15totheappropri
Listentothedirectionsandmatchtheplacesinquestions11-15totheappropri
Listentothedirectionsandmatchtheplacesinquestions11-15totheappropri
Listentothedirectionsandmatchtheplacesinquestions11-15totheappropri
随机试题
下列项目中,可能引起资本公积变动的有( )。 Ⅰ.与发行权益性证券直接相关的
下列关于关系人的表述,错误的是()。A.关系人包括商业银行的管理人员及其近亲
A.4 B.6 C.8 D.9
租车公司的商务车数量比小客车少16辆,某日租出商务车、小客车各16辆后,剩下的小
从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性: A.如
根据以下资料,回答下列问题。 2011年公立医院诊疗人次占全国医疗卫生机构
与契约型基金比较而言,下列不属于公司型基金特点的是()。A.投资者对基金运用没有
1988年版《巴塞尔资本协议》规定商业银行资本充足率不得低于()。A.8%
计算工程单价的依据不包括()。A.人工单价 B.材料价格 C.机械台班
施工质量的过程控制要求高主要是因为建筑产品生产过程( )。A.影响因素多
最新回复
(
0
)