  The neuronal mechanisms that serve to distinguish between light-emitting and
light reflecting objects are largely unknown. It has been suggested that
luminosity perception implements a separate pathway in the visual system, such
that luminosity constitutes an independent perceptual feature. Recently, a
psychophysical study was conducted to address the question whether luminosity
has a feature status or not. However, the results of this study lend support to
the hypothesis that luminance gradients are instead a perceptual feature. Here,
I show how the perception of luminosity can emerge from a previously proposed
neuronal architecture for generating representations of luminance gradients.
