Effects of dividing attention on the memory-block effect.

S. M. Smith and D. R. Tindell (1997) reported that prior study of words that are orthographically similar to the solutions of test word fragments (e.g., studying ANALOGY and completing the fragment A_L _ _GY, whose solution is ALLERGY) reduced the fragment completion rate relative to a baseline condition in which unrelated words were studied. They called this effect the memory-block effect. In the present experiment, the authors replicated this effect using a larger set of materials than that used by S. M. Smith and D. R. Tindell. The authors also found that dividing attention at study eliminated the memory-block effect. This pattern mimicked the effect of dividing attention on recognition memory but differed from the effect on repetition priming effects. The authors suggest that the memory-block effect is driven by a mechanism different from that responsible for producing repetition priming effects in an implicit fragment completion test.