Information persistence: Testing spatial and identity information with a voice probe

Summary Two experiments tested loss of information from iconic memory. In the first, subjects were shown a row of letters for 50 ms and were asked whether or not a named letter had been present in the display. The name was spoken at an SOA of –150, 0, 50, 100, or 200 ms. In the second experiment, the named letter was always present in the display, and the subjects were asked to identify its location in the row. Accuracy was independent of the SOA in the first experiment but dropped rapidly as the SOA increased in the second. Thus, subjects lose information needed to locate material in space, not information about the identity of the material.