1.   His brain was working overtime now.

2.   In the past twenty years, we have greatly increased our knowledge of how the brain works.

3.   My brain worked fast as I tried to Decide what to do.

4.   Progress in learning how alcohol and caffeine work has had to wait for new knowledge of how the brain works.

5.   This discovery has revolutionized our understanding of how the human brain works.

6.   Scientists are learning more about how the human brain works.

7.   In fact many people believe that we are only now really starting to learn the truth about how the human brain works.

8.   Scientists hope that if we can discover how the brain works, the better use we will be able to put it to.

9.   As she put down the phone, her brain was working overtime.