Sensory registration and informational persistence.

The traditional view of iconic memory as a precategorical, high-capacity, quickly decaying visible memory has recently come under attack (e.g., Coltheart, 1980). Specifically, distinctions have been drawn between visible persistence, or the phenomenal trace of an extinguished stimulus, and informational persistence, knowledge about the visual properties of the stimulus. In the present research we tested two alternative conceptions of informational persistence. One conception is that visual information persists in a visual memory that begins at stimulus offset and lasts for 150-300 ms, independently of exposure duration. The second is that informational persistence arises from a nonvisual memory that contains spatial coordinates for displayed items along with identity codes for those items. Three experiments were conducted in which 3 X 3 letter arrays were presented for durations ranging from 50 to 500 ms. A single character mask presented at varying intervals after array offset cued report of an entire row of the array. Comparison of the cued row's masked and unmasked letters revealed that spatially-specific visual (i.e., maskable) information persisted after stimulus offset, regardless of exposure duration. This result favors the visual conception of informational persistence. But there was also support for the nonvisual conception: Accuracy increased and item intrusion errors decreased as stimulus duration increased. The implications of these results for models of informational persistence and for transsaccadic integration during reading are discussed.