The neural mechanisms setting the lower limit of conscious visual perception in humans is not fully understood. Here the authors show by correlating human vision experiments and non-human primate retina recordings that primates rely on the retinal ON pathway in perception of the dimmest light increments, and that nonlinear thresholding in this pathway eliminates single photons and neural noise thereby allowing perception of minute differences in light intensity.
- Markku Kilpeläinen
- Johan Westö
- Petri Ala-Laurila
