The Search for Correspondences between Subjective and Physical Aspects of Nature, and the Evidence for a Correspondence between Visual Sensations and Retinal Ganglion Cells

The double-aspect theory of mind-brain connectedness posits that Nature's physical aspect includes brain cells which can interact mechanistically, whereas Nature's subjective aspect includes conscious sensations which carry intrinsic subjective value. Scientifically, double-aspect naturalism implies that specific sensations should correspond to unique brain cells. But since the middle of the twentieth century, neuroscientists have been unable to find any neuronal cell-types that are unique to visual cortex and distinguishable from neurons in auditory and somatosensory cortex. The present article alternatively explores findings rooted in retinal anatomy, afterimage psychophysiology, and visualimage-induced electroretinography. Collectively, these findings suggest that conscious visual sensations of a particular color or particular brightness correspond not to neurons in the visual cortex, but to retinal ganglion cells that are structurally unique in their form and composition.