Exploration of all sorts is rooted in the notion of takingrisks. Riskunderlies any journeyinto
the unknown, whether it is a shipcaptain’s voyageinto the unchartedseas, a scientist’s research on
dangerousdiseases, or an entrepreneur’s investment in a new venture. But whatexactlypushedChristopherColumbus to embark on a voyageacross the Atlantic, or EdwardJenner to test his
theory for an earlysmallpoxvaccine on a child, or HenryFord to bet thatautomobilescouldreplacehorses?
Manypeoplewillinglyexposethemselves to varyingdegrees of risk in theirpursuit of certaingoals, likefinancialreward, politicalgain, or savinglives. But as the dangerincreases, the number
of peoplewilling to go forwardshrinks, until the onlyones who remain are the extremerisktakers.
Scientistshavebegun to open up the neurologicalblack box containing the mechanisms for
risk-taking and tease out the biologicalfactorsthat may promptsomeone to become an explorer.
Theirresearch has centered on neurotransmitters, the chemicalsthatcontrolcommunication in the
brain. One neurotransmitterthat is crucial to the risk-takingequation is dopamine, whichhelpscontrolmotorskills but alsohelpsdrive us to seek out and learn new things as well as processemotionssuch as anxiety and fear. Peoplewhosebrains don’t produceenoughdopamine, such as
those who are afflictedwithParkinson’s disease, oftenstrugglewithapathy and a lack of
On the opposite end of the spectrum, robustdopamineproductionholds one of the keys to
understandingrisk-taking, saysLarryZweifel, a neurobiologist at the University of Washington.
“When you’re talkingaboutsomeone who takesrisks to accomplishsomething—climb a mountain,
start a company, run for office, become a NavySEAL—that’s driven by motivation, and motivation
is driven by the dopaminesystem. That is whatcompelshumans to moveforward.”
Dopaminehelpselicit a sense of satisfactionwhen we accomplishtasks: the riskier the task, the
larger the hit of dopamine. Part of the reason we don’t all climbmountains or run for office is that
we don’t have the sameamount of dopamine. Molecules on the surface of nervecellscalledautoreceptorscontrol how muchdopamine we make and use, essentiallycontrolling our appetite for risk. 【題組】37. What do the wordstease out in paragraph 3 mean?
(A) entangle (B) unravel (C) weave (D) satirize (E) separate