5．While some scientists overlook the existence of a sixth sense for danger，a new research from Washington University in St．Louis has discovered a brain area that clearly acts as an early warning system and helps us adjust our behavior to avoid dangerous situations．
"Our brains are better at picking up not obvious warning signs than we previously thought，"said Joshua Brown，a PhD in psychology in the issue of the journal Science．
The findings offer exact scientific evidence for a new way to form a concept of the complex control processes taking place in and around the ACC，a brain area located near the top of the frontal lobes （耳垂） and along the walls that divide the left and right hemispheres （大脑半球）．
"In the past，we found activity in the ACC when people had to make a difficult decision，or after they make a mistake，"Brown said．"But now we find that this brain area can actually learn to recognize when you might make a mistake，even before a difficult decision has to be made．So the ACC appears to act as an early warning system--it learns to warn us in advance when our behavior might lead to a negative outcome，so that we can be more careful and avoid making a mistake．"
By providing a clearer picture by which we self monitor and control our behavior，the study is an important step in efforts to develop more effective treatments for mental illnesses．It also provides a new way of understanding inappropriate behaviors that often accompany mental illnesses．
"Our results suggest how injury of the ACC can lead to breakdowns in the early warning system，so that the brain fails to stop or control inappropriate behavior ahead of time，"said Brown．
"On the other hand，in those persons with mental disorder，the ACC might warn us of an upcoming problem even when no problem is in the existence．"
Known to be an important part of the brain's control system，the ACC is believed to help adjust between cold，hard，fact-based reasoning and emotional responses，such as love，fear or expectation．
68．According to the passage，the ACCD．
A．refers to the sixth sense for danger
B．deals with obvious warning situations
C．connects the left and right hemispheres
D．sends warning messages in advance
69．The new research is beneficial because itC．
A．provides a new way of avoiding mistakes
B．adjusts emotional responses in time of danger
C．helps find better treatments for mental illnesses
D．assists people in predicting and avoiding danger
70．The new research helps us understandA．
A．why we are likely to make mistakes when the ACC is badly injured
B．why people with illnesses usually have so many strange behaviors
C．how the ACC works when something dangerous happens
D．how our brain warns us of failure in advance．
分析 尽管一些科学家忽视了第六感预见危险的存在，但华盛顿大学-圣路易斯的一项新研究发现，大脑区域显然可以作为一个早期预警系统，帮助我们调整我们的行为以避免危险．
解答 68．D．词义猜测题．根据第四段So the ACC appears to act as an early warning system--it learns to warnus in advance when our behavior might lead to a negative outcome，so that we can be more careful and avoid making a mistake．"所以ACC似乎充当着一个早期预警系统的角色，当我们的行为可能会导致负面的结果时，它会提前提醒我们，以便使我们能更小心，避免犯错误．故选D．
69．C．细节理解题．根据第五段By providing a clearer picture by which we self monitor and control our behavior，the study is an important step in efforts to develop more effective treatments for mental illnesses．通过提供一个由我们自我监控和控制我们的行为的更清晰的图片，这项研究在努力开发更有效的治疗精神疾病上迈出了重要一步．故选C．
70．A．细节理解题．根据文章倒数第三段"Our results suggest how injury of the ACC can lead to breakdowns in the early warning system，so that the brain fails to stop or control inappropriate behavior ahead of time"我们的研究结果显示，有损伤的ACC可以导致预警系统故障，使大脑无法停止或者提前控制不恰当的行为；故选A．
点评 考察学生的细节理解和推理判断能力，做细节理解题时一定要找到文章中的原句，和题干进行比较，再做出正确的选择．在做推理判断题不要以个人的主观想象代替文章的事实，要根据文章事实进行合乎逻辑的推理判断．
