what were the results of sperling's partial-report procedure
Iconic memory The partial report condition required participants to identify a subset of the characters from the visual display using cued recall. The cue was a tone which sounded at various time intervals (~50 ms) following the offset of the stimulus. The frequency of the tone (high, medium, or low) indicated which set of characters within the display were to be reported. Due to the fact that participants did not know which row would be cued for recall, performance in the partial report condition can be regarded as a random sample of an observer's memory for the entire display. This type of sampling revealed that immediately after stimulus offset, participants could recall most letters (9 out of 12 letters) in a given row suggesting that 75% of the entire visual display was accessible to memory.[1] This is a dramatic increase in the hypothesized capacity of iconic memory derived from full-report trials.