The modern view is that vision is an active process. In binocular rivalry, for example, the sensory and intentional processes in the brain need to be "matched" in order for us to "see". Elucidating the neural mechanisms of active vision is important in clarifying how the visual system captures the external world in a flexible and dynamic way.
Taya, F. and Mogi, K. (2005) Spatio-temporal dynamics of the visual system revealed in binocular rivalry. Neuroscience Letters 381 (1-2): 63-68.