There have been hundreds of studies on the spacing effect — we've known about it since the 1880s.

关于间隔效应的研究已经有数百个了，人们在19世纪80年代就知道了。

One of the most well-supported tricks to up information retention is to use a technique called the spacing effect, or spaced practice.

提高信息保留率最有效的技巧是使用一种称为间隔效应的技术，或者称为间隔练习。