On the optimal viewing position for object processing

Abstract

Numerous studies have shown that a visually presented word is processed most easily when participants initially fixate just to the left of the word's center. Fixating on this optimal viewing position (OVP) results in shorter response times and a lower probability of making additional withinword refixations (OVP effects), but also longer initialfixation durations (an inverted-OVP or I-OVP effect), as compared to initially fixating at the beginning or the end of the word. Thus, typical curves are u-shaped (or inverted-ushaped), with a leftward bias. Most researchers explain the u-shape in terms of visual constraints, and the leftward bias in terms of language constraints. Previous studies have demonstrated that (I)-OVP effects are not specific to words, but generalize to object viewing. We further investigated this by comparing the strength and (a)symmetry of (I-)OVP effects for words and objects. To this purpose, we gave participants an object-versus word-naming task in which we manipulated the position at which they initially fixated the stimulus (i.e., a line drawing or the written name of an object). Our results showed that object viewing, just as word viewing, resulted in u-shaped (I-)OVP curves. However, the effect was weaker than for words. Furthermore, for words, the curves were biased to the left, whereas they were symmetrical for objects. This might indicate that part of the (I-)OVP effect for words is language specific, and that (I-)OVP effects for objects are a purer measure of the effect of visual constraints.

The preferred viewing location in top-to-bottom sentence reading

“…When readers do not fixate in this most convenient location, they are more likely to make a short fixation and then refixate the same word on their next saccade (see also Rayner, Sereno, & Raney, 1996). This is in contrast to the effects seen in single word recognition where a word is processed most rapidly when it is fixated at its center, at the optimal viewing location (OVL; e.g., McConkie, Kerr, Reddix, Zola, & Jacobs, 1989; Rayner et al, 1996; Vitu, O’Regan, & Mittau, 1990, but see O’Regan & Jacobs, 1992 and van der Linden & Vitu, 2016 who report a leftward bias). 1…”

“…1. Research on object and scene perception echo these findings; viewers process isolated objects fastest when fixations are centrally located compared to more peripheral (Foulsham & Kingstone, 2013;van der Linden & Vitu, 2016), but viewers tend to undershoot the centers of objects embedded within a scene (Foulsham & Kingstone, 2013;Nuthmann & Henderson, 2010). 2.…”

“…In the nearly 40 years since Rayner (1979), Dunn-Rankin (1978), and O’Regan (1981) published their findings, many researchers have replicated this preferred landing position effect during normal sentence reading 2 (e.g., McConkie et al, 1989; Nuthmann, Engbert, & Kliegl, 2005; Nuthmann & Kliegl, 2009; Rayner, Fischer, & Pollatsek, 1998; Rayner et al, 1996; van der Linden & Vitu, 2016; Vitu, McConkie, Kerr, & O’Regan, 2001; Vitu et al, 1990, see Vitu, 2011 for a review). Word length and launch site strongly influence the PVL (McConkie, Kerr, Reddix, & Zola, 1988; Nuthmann et al, 2005; Radach & McConkie, 1998; Rayner et al, 1996).…”

“…When readers do not fixate in this most convenient location, they are more likely to make a short fixation and then refixate the same word on their next saccade (see also Rayner, Sereno, & Raney, 1996). This is in contrast to the effects seen in single word recognition where a word is processed most rapidly when it is fixated at its center, at the optimal viewing location (OVL; e.g., McConkie, Kerr, Reddix, Zola, & Jacobs, 1989;Rayner et al, 1996;Vitu, O'Regan, & Mittau, 1990, but see O'Regan & Jacobs, 1992and van der Linden & Vitu, 2016 who report a leftward bias). 1 In the nearly 40 years since Rayner (1979), Dunn-Rankin (1978), and O'Regan (1981) published their findings, many researchers have replicated this preferred landing position effect during normal sentence reading 2 (e.g., McConkie et al, 1989;Nuthmann & Kliegl, 2009;Rayner, Fischer, & Pollatsek, 1998;Rayner et al, 1996;van der Linden & Vitu, 2016;Vitu, McConkie, Kerr, & O'Regan, 2001;Vitu et al, 1990, see Vitu, 2011 for a review).…”

Picture perfect: A stimulus set of 225 pairs of matched clipart and photographic images normed by Mechanical Turk and laboratory participants

“…At the object level, for example, recognition is known to be influenced by factors such as shape (e.g., Biederman, 1987 ; Biederman & Ju, 1988 ; Sharma, Gupta, & Malik, 2012 ) and orientation (Bartram, 1976 ; Lawson & Humphreys, 1996 ), as well as by the earlier-mentioned influences of color. In addition, studies of eye movement behavior have demonstrated an optimal viewing position for object recognition, whereby initial eye fixations are programmed to land on the center of a target object from the viewer’s point of gaze (Foulsham & Kingstone, 2013 ; Henderson, 1993 ; van der Linden & Vitu, 2016 ). In studies in which multiple 2-D images are presented within the same display, fixations to various objects will be planned using parafoveal information.…”