The local border mechanism in grating induction

Both White's effect and the grating induction effect are examples of brightness contrast phenomena. Models to account for these effects have either explicitly rejected local border mechanisms (such as retinal ganglion cells) in favour of cortical mechanisms, or explicitly rejected elongated cortical filters in favour of local mechanisms. We have argued that any viable model must include both classes of mechanism. In this paper we present some novel versions of induction effects, and describe the explanatory power of a model couched solely in terms of the operation of local spatial filters. The model employs filters at different spatial scales whose outputs are then averaged. Using this approach it is possible to give a good account not only for the novel demonstrations we present, but also for the pattern of results reported by others concerning various manipulations of the spatial parameters of induction displays.