Locus of short-term visual storage.

A rod monochromat can preserve visual information in iconic memory even when the initial stimulus is invisible to the subject. Since the initial invisibility is due to rod saturation, it can be shown that all the information must have been stored inside the photoreceptors. Because the spectral sensitivity for producing icons in normal subjects is that of the rods, the conclusion is that in normal subjects, under ordinary viewing conditions, the photoreceptors are the primary store for iconic memory.