ABSTRACT
A functional hierarchy of unconscious processing, based strictly on results of psychophysical research, is updated in the light of more recent such research that resolves inconsistencies among prior experimental findings. Seen as an evolving and thus a revisable hierarchy, it defines a useful and informative program for future research on different types and levels of unconscious processing. Based on the fact that the nonlinearity of neuronal contrast response functions increases from lower to higher visual processing levels, it is also possible, via degree of nonlinearity obtained psychophysically, to relate the functional hierarchy to its corresponding anatomical hierarchy of cortical processing. Moreover, this can serve as a guide to brain-recording studies that more clearly delineate the anatomical hierarchy of unconscious cortical processing. Experimental and meta-analytic research can thus arrive at an increasingly refined picture characterizing the relation between the functional and the anatomical cortical hierarchy of unconscious processing.
