Binocular Vision: Defining the Historical Directions

Abstract

Ever since Kepler described the image-forming properties of the eye (400 years ago) there has been a widespread belief, which remains to this day, that an object seen with one eye is always seen where it is. Predictions made by Ptolemy in the first century, Alhazen in the eleventh, and Wells in the eighteenth, and supported by Towne, Hering, and LeConte in the nineteenth century, however, are contrary to this claimed veridicality. We discuss how among eighteenth- and nineteenth-century British researchers, particularly Porterfield, Brewster, and Wheatstone, the erroneous idea continued and also why observations made by Wells were neither understood nor appreciated. Finally, we discuss recent data, obtained with a new method, that further support Wells's predictions and which show that a distinction between headcentric and relative direction tasks is needed to appreciate the predictions.

The role of monocularly visible regions in depth and surface perception

“…If some transformation occurred to deliver a representation from that point, the brain would have to squeeze the region defined by the separation between points a and d (the right eye view in figure 7), into a smaller region separating a' and d' (the view as if from a single central location). How, or even if, this is done is still a hotly debated topic and beyond the scope of this review, but the interested reader is directed to Erkelens & van Ee (2002) and Ono, Mapp & Howard (2002) and for reviews see Howard & Rogers (2002) and Ono et al (2009). Forte et al (2002) studied the stability of monocular regions when there was no binocularly visible background, but regions of the background surface were visible to one eye or the other (e.g.…”

Two historical strands in studying visual direction1

“…In doing so we strive to give an historical account that is simple yet accurate. For a more complete and detailed discussion of research on visual direction, readers are referred to Mapp, Ono, and Howard (2002, in press), for discussions of researches during the 17th and 18th centuries to Wade (1998), Wade, Ono, and Mapp (2006) and Ono et al. (2009), and for a discussion of current research to Marlow (2010).…”

“…Since antiquity, the history of research on visual direction has reflected a struggle between two approaches (Ono, Wade, & Lillakas, 2009;Shimono & Wade, 2002;Wade & Swanston, 1996), and the struggle continues today. One is based principally on observation or phenomenology, initially with relatively little in the way of theory about the underlying mechanism.This approach eventually leads to a summary of observations in the form of propositions, principles, or laws of visual direction.…”

The Singular Vision of William Charles Wells (1757–1817)

“…Brewster (1844aBrewster ( , 1844b, the most prestigious Scottish researcher on optics, acknowledged Proposition I in accounting for one of the illusions he was discussing (1844a), but in the same year he proposed the "law" of visible direction that was identical to that of Porterfield's (1737) axiom (1844b). We (Ono, Wade, & Lillakas, 2009) have speculated that Wheatstone and Brewster would have examined the propositions and their tests more closely, if Wells had explicitly stated that the propositions predict outcomes contrary to Porterfield's axiom. Whatever the reason, Wells did not.…”

“…Following this analysis of the eye as an optical instrument, the prevalent view was that objects seen with either eye are localized correctly. Such statements regarding visual direction can be found in English by writers such as Porterfield (1737), Smith (1738), Reid (1764), Young (1801), and Brewster (1830); see Ono, Wade, and Lillakas (2009) for a review. Among these writers, Porterfield (1737) made the most explicit and succinct statement; he was so confident of its validity that he called it an axiom.…”