figure 6.2 Sperling’s iconic memory paradigm In a study of the capacity of sensory memory, Sperling showed participants a series of letters for a very brief period of time. Immediately afterward, he sounded a tone that indicated which row of letters the participant should try to recall. Participants could recall most of the letters in the row, which showed that their sensory memory, for a brief amount of time, contained a large amount of information.