ABSTRACT

In Parts II and III of this book, we reviewed theories and evidence that contribute to understanding two broad functions of visual perception; to provide knowledge and awareness of the world around us and to guide our activities within it. This distinction is more than just an arbitrary and convenient one, and there are two main reasons why it might be adopted. First, Milner and Goodale’s (1995) theory suggests that it reflects the way that the brain handles visual information. If awareness relies exclusively on processing in a ventral pathway, and visuomotor control on processing in a dorsal pathway, it would make sense to consider these two aspects of visual perception separately. As we saw in Chapter 3, however, there is evidence that the two pathways interact closely and are themselves divided into multiple subsystems. It is therefore premature to base a fundamental distinction between two functions of vision on current neurological evidence.