  The idea that careful psychophysical work with could help us understand the nature of their subjective experiences of the world can be traced at least to Donald Griffin's experimental tests of the limits of bat echolocation. It is also behind the idea that knowing that horses have near 360° vision, or that raptors have two fovea on each retina, may tell us something about the nature of their experiences — how the world appears to them — if it is granted that they have such experiences. Neural investigation adds a further layer of analysis to scientific understanding of the nature of perception. For instance, Leopold &amp; Logothetis (1996) used neural data to support inferences about the percepts of monkeys under conditions of binocular rivalry (see also: Myserson et al. 1981; Rees et al. 2002). And Leopold et al. (2003) argue that neural recordings can be used to corroborate the non-verbal “reports” of monkeys shown ambiguous visual stimuli.  (Think here of whether it is possible for the monkey to report that it is subject to Gestalt switches like those arising from ambiguous figures such as the duck-rabbit or figure-vase illusions.)