Mach bands, Hermann grid, and lateral inhibition in the retina
Literature about two illusions that are traditionally linked to lateral inhibitory processes in the retina is surveyed. Despite much research and a long history, the Mach bands illusion has not yet been very well-understood. Quantitative data is lacking, while qualitative data is controversial. The Hennann Grid illusion, equally old, has not yet been fully explored either. A critical and a comparative review of the experiments and the conclusions is carried out, noting common results as well as contradictory ones. New experiments and a different method of measurement are then proposed. Some preliminary experiments and their results are included in the appendix together with a review of recent knowledge about the primate retina and its functioning.