雅思阅读模拟试题学术类 关于这个问题下面小编就来为各个考生解答下。
雅思阅读模拟试题学术类
READING PASSAGE 2
You should spend about 20 minutes on Questions 14–26, which are based on Reading
Passage 2 below.
The Triune1
Brain
The first of our three brains to evolve is what scientists call the reptilian cortex. This brain
sustains the elementary activities of animal survival such as respiration, adequate rest
and a beating heart. We are not required to consciously “think” about these activities.
The reptilian cortex also houses the “startle centre”, a mechanism that facilitates swift
reactions to unexpected occurrences in our surroundings. That panicked lurch you
experience when a door slams shut somewhere in the house, or the heightened
awareness you feel when a twig cracks in a nearby bush while out on an evening stroll
are both examples of the reptilian cortex at work. When it comes to our interaction with
others, the reptilian brain offers up only the most basic impulses: aggression, mating,
and territorial defence. There is no great difference, in this sense, between a crocodile
defending its spot along the river and a turf war between two urban gangs.
Although the lizard may stake a claim to its habitat, it exerts total indifference toward the
well-being of its young. Listen to the anguished squeal of a dolphin separated from its
pod or witness the sight of elephants mourning their dead, however, and it is clear that a
new development is at play. Scientists have identified this as the limbic cortex. Unique to
mammals, the limbic cortex impels creatures to nurture their offspring by delivering
feelings of tenderness and warmth to the parent when children are nearby. These same
sensations also cause mammals to develop various types of social relations and kinship
networks. When we are with others of “our kind” – be it at soccer practice, church,
school or a nightclub – we experience positive sensations of togetherness, solidarity and
comfort. If we spend too long away from these networks, then loneliness sets in and
encourages us to seek companionship.
Only human capabilities extend far beyond the scope of these two cortexes. Humans
eat, sleep and play, but we also speak, plot, rationalise and debate finer points of
morality. Our unique abilities are the result of an expansive third brain – the neocortex –
which engages with logic, reason and ideas. The power of the neocortex comes from its
ability to think beyond the present, concrete moment. While other mammals are mainly
restricted to impulsive actions , humans can think about the “big picture”. We can string together simple
lessons to develop complex theories of physical or social phenomena .
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