Configurational asymmetry in vernier offset detection

Abstract

Two psychophysical experiments were conducted at the horizontal and vertical orientations respectively, demonstrating substantial main effect of configuration, but no effect of offset direction on vernier acuity. In Experiment 1, a pair of horizontal bars were arranged side by side with a large gap between them. The observers were, on average, significantly better at discriminating a vertical offset if the right-hand bar was below the left-hand bar than vice versa, regardless of which bar they experienced as displaced and which as constant. A similar asymmetry was evident in Experiment 2 where observers judged horizontal offset for a pair of vertically oriented bars, where one was placed above the other. In this case average performance was better if the upper bar was on the right of the lower bar rather than on its left. There were large individual variations in the asymmetrical trend, but the effect could not be explained by subjective response bias. Furthermore, vernier acuity improved significantly and the asymmetry decreased more or less as a function of training. The average asymmetrical trend was consistent across training days and across two orientations, which indicates that the processing of line vernier stimuli is possibly configuration-specific in the cardinal orientation.

Anticlockwise or clockwise? A dynamic Perception-Action-Laterality model for directionality bias in visuospatial functioning

“…If the findings of Karim and Kojima (2010a) are compared to the findings about aesthetics of visual arts (see prior section) we see that there is a consistency between perceptual precision and aesthetic preference: what is oriented from left-to-right direction is more understandable and aesthetically more appealing than what is oriented from right-to-left direction, possibly due to the increased efficiency of information processing at that orientation. Though the stimuli that Karim and Kojima used in their studies were different from the stimuli used in the aesthetic judgment studies, they all possess a common feature of the directionality in their configurations (Figures 1, 2, 3).…”

“…There is clear evidence of the cardinal superiority over the oblique orientation, and its neural basis (Furmanski & Engel, 2000; Li et al, 2003). In addition to the evidence of the orientation effect, some recent studies have demonstrated that our visuo-spatial performance can vary even within an orientation depending on spatial organization or layout of the stimuli (Figure 3; Karim & Kojima, 2010a,b; for a review, see Karim & Kojima, 2010c). In one study, Karim and Kojima (2010a) found that observers were generally better at discriminating a vertical offset for a pair of horizontal light bars (vernier features) arranged side-by-side with a large gap between them if the right-hand bar was below the left-hand bar than vice versa (Figure 3A,B; horizontal).…”

“…In addition to the evidence of the orientation effect, some recent studies have demonstrated that our visuo-spatial performance can vary even within an orientation depending on spatial organization or layout of the stimuli (Figure 3; Karim & Kojima, 2010a,b; for a review, see Karim & Kojima, 2010c). In one study, Karim and Kojima (2010a) found that observers were generally better at discriminating a vertical offset for a pair of horizontal light bars (vernier features) arranged side-by-side with a large gap between them if the right-hand bar was below the left-hand bar than vice versa (Figure 3A,B; horizontal). Similarly, for a pair of vertically oriented light bars, one above the other, the horizontal offset detection was better if the lower bar was on the left of the upper bar rather than on its right (Figure 3A,B; vertical).…”

“…However, there were some individual differences, with a few observers showing an opposite trend as an exception to the overall findings in both these studies. Karim and Kojima (2010a) associated these findings with neuronal preference or with cerebral lateralization via handedness of the observers.…”

“…People usually prefer pictorial arrangements that possess left-to-right directional cues over their mirror reversed pictures; and this preference can be associated with handedness (Freimuth & Wapner, 1979; McLaughlin, Dean & Stanley, 1983; Mead & McLaughlin, 1992) and cultural factors, such as reading/writing habits (Chokron & De Agostini, 2000; Friedrich & Elias, 2016). In addition to such a horizontal directionality bias in aesthetic judgment of visual arts, further evidence indicates that left-to-right directional preference or bias might also occur in other visuospatial tasks, such as line bisection (Bowers & Heilman, 1980; for a metaanalytic review, see Jewell & McCourt, 2000) and vernier offset detection (Karim & Kojima, 2010a, b). On the other hand, the most widely known behavioral lateralization is the earliest demonstration that humans prefer to turn rightward rather than leftward (Blumenthal, 1928; Brigden, 1935; Gesell, 1938; Gesell & Ames, 1950; Lund, 1930; Szymanski, 1913; Turkewitz, Gordon, & Birch, 1965a,b), although some contradictory findings have emerged in other studies (Mohr & Bracha, 2004; Mohr, Brugger, Bracha, Landis, & Viaud-Delmon, 2004; Mohr, Landis, Bracha, & Brugger 2003; Toussaint & Fagard, 2008).…”