“Source monitoring” theory is applied to the turn-of-the-century argument that, whenever binocularly fused patterns are self-consciously apperceived, both eyes' monocular sensations are consciously perceived. According to monitoring theory's refinement of the argument, binocularly apperceived patterns are accompanied by selfconsciousness that one is perceiving patterns , whereas monocular sensations are accompanied by no self-consciousness of their source. In the current test of this refined argument, 32 subjects were monocularly presented with 6 letters of the alphabet, while binocularly fusing 6 different letters, (...) and were subsequently required to discriminate these 12 letters from 6 other letters that they had visually imaged. Consistent with monitoring theory, the results of experimental testing suggest that binocularly fused letters are neurally monitored as “peripheral,” self-consciously experienced as “perceived,” and subsequently remembered as not “imaged.” The results further suggest that, during such binocular apperception, monocular data are not totally unconscious-like computer data-but are consciously experienced as “sourceless” sensations that are memorially confused with visually imaged sensations. (shrink)