|From Purves Lab|
The standard account of Mach bands has to do with lateral inhibition in the retina. But, Gibson writes things that seem to be highly dismissive of a) not just of this account, but of any such accounts and of b) attempts to understand them.
Not even the current theory that the inputs of the sensory channels are subject to "cognitive processing" will do. The inputs are described in terms of information theory, but the processes are described in terms of old-fashioned mental acts: recognition, interpretation, inference, concepts, ideas, and storage and retrieval of ideas. These are still the operations of the mind upon the deliverances of the senses, and there are too many perplexities entailed in this theory. It will not do, and the approach should be abandoned....
Let us remember once again that it is the perception of the environment that we wish to explain. If we were content to explain only the perception of forms or pictures on a surface, of nonsense figures to which meanings must be attached, of discrete, stimuli imposed on an observer willy-nilly, in short, the items most often presented to an observer in the laboratory, the traditional theories might prove to be adequate and would not have to be abandoned. But we should not be content with that limited aim. (Gibson, 1979, pp. 238-9).http://www.purveslab.net/research/explanation/brightness/mach.html#f1