  The divisive normalization-or-feedforward-inhibition (DNFI) model {#sec000} -----------------------------------------------------------------  The divisive normalization-or-feedforward-inhibition (DNFI) model (**[Fig 0B](#pone.0000000.g000){ref-type="fig"}**) \[[@pone.0000000.ref000]--[@pone.0000000.ref000]\] is 