The anatomy of free recall.

The relative importance of various covert cues used in free recall is inferred on the basis of conditional probabilities of free recall given success vs failure of cued recall of the same material. Thirty-six names associated with pictures arranged in a 6 by 6 matrix were learned. A free recall test of names was followed by cued recall of names, with pictures, positions, or joint pictures and positions used as cues. Matching tests based on these cues were also administered. The tests were given at one of two stages of training, immediately or after 2 days. Pictorial and position cues are equally well encoded, but pictorial cues are less accessible and, therefore, relatively more useful in cued recall than in free recall. Position and pictorial information related to the names appears to be encoded and forgotten independently, and there is no evidence for summation of subthreshold encoding effect.