Another test involved counting backwards by sevens from 9, 095.

另一项测试中，被试要求从9095开始，逐一减7倒数。

youdao

When you are finished, return to alertness by counting backwards from 5 to 1.

上边完成后，从5倒数到1，让自己回到警觉状态。

youdao

Try counting backwards from 100 by 3's, or saying the alphabet backwards, etc.

试一试以3为间隔从100倒数数，或者，倒背字母表。

youdao

They found that different networks in the brain work together when you are counting backwards from 5, 000 by threes than when the brain is resting.

FORBES: Scientists At Stanford Come Up With 'Mind-Reading' Imaging Technique