In this section, we review several experiments demonstrating the
basic testing effect, the fact that information retrieved from memory leads
to better performance on a later test. There are perhaps a hundred
experiments we could choose from, but we have selected two straightforward
ones from our own lab to make the case. The first experiment
used easily nameable pictures as materials (the kind of material that
experimental psychologists like to use) whereas the second experiment
used nonfiction prose materials more relevant to education. However, the
basic testing effect has been obtained with many other types of materials,
such as foreign language vocabulary, map reading, general knowledge
questions, and so on.
Wheeler and Roediger (1992) conducted an experiment in which a
strong testing effect occurred, although the experiment was mostly about
a different topic. We present selected conditions here from their experiment
to make our points about testing. Their subjects saw 60 pictures