When encoding fails: instructions, feedback, and registration without learning.

Four experiments replicated and extended the registration-without-learning effect, in which there is little improvement in the ability to discriminate an old target (X) from a highly similar test item (Y) after the first few presentations of X, even though judgments of frequency continue to rise in an open-ended fashion. Forced-choice testing revealed the anomalous form of the learning curve for X-Y discrimination (faster and then slower than the exponential). Effects of several different learning instructions were compared, but these appeared to affect only the level of initial learning, and to do little to promote X-Y discrimination learning on later presentations. The opportunity for self-testing with feedback during study provided no benefits when responding was covert, but did when overt anticipation was required. The findings are discussed in relation to the roles of bottom-up and top-down processing in memory encoding, and to the importance of error-correcting feedback in further structural learning of materials, once the materials have become familiar.