THE HIERARCHICAL NATURE OF PERCEIVING DIRECTION OF MOTION IN-DEPTH FROM OPTIC FLOW

Monocular adaptation to flow fields of optic expansion and contraction juxtaposed on either side of fixation influenced subsequently perceiv ed rotation direction of a figure rotating in depth (kinetic depth eff ect) about its vertical axis with a normally ambiguous direction. This influence was shown to be asymmetric since adapting to optic expansio n produced significantly more aftereffects of translation in depth tha n did adapting to perceived rotation in depth when viewing a neutral t est stimulus. The results are evidence for a hierarchical processing m odel for the perception of motion in depth from optic flow. Serendipit ously, we discovered a new aftereffect from viewing kinetic depth rota tion with direction specified by proximity-luminance covariation (PLC) . The results and other research are discussed in terms of neural netw ork models with synergistic interactions between levels.