ABSTRACT
This chapter shows that the colours animals perceive are different from those that humans do, but that pitch is the same across the board. The colours that result are quite different from those that humans experience. Colour and auditory pitch are both wavelength-related property systems. The auditory system and the speech perception system extract detailed information from the incoming acoustic signal. Colour sensitivity would be improved by adding cone-cells, but this reduces spatial resolution, since more cells have to be packed into each location. Cone-cells are distinguished one from another by a response curve more than by peak sensitivity. The function of opponent processing is to remove the correlated portions of cone-cell response, which are due to brightness, so as to arrive at the uncorrelated portion, which is due to wavelength. Constancy processing modifies and adjusts the cone-cell response so that it varies less than the light received changes.
