The role of sensory ocular dominance on through-focus visual performance in monovision presbyopia corrections

Abstract

Monovision presbyopia interventions exploit the binocular nature of the visual system by independently manipulating the optical properties of the two eyes. It is unclear, however, how individual variations in ocular dominance affect visual function in monovision corrections. Here, we examined the impact of sensory ocular dominance on visual performance in both traditional and modified monovision presbyopic corrections. We recently developed a binocular adaptive optics vision simulator to correct subjects' native aberrations and induce either modified monovision (1.5 D anisometropia, spherical aberration of +0.1 and -0.4 μm in distance and near eyes, respectively, over 4 mm pupils) or traditional monovision (1.5 D anisometropia). To quantify both the sign and the degree of ocular dominance, we utilized binocular rivalry to estimate stimulus contrast ratios that yield balanced dominance durations for the two eyes. Through-focus visual acuity and contrast sensitivity were measured under two conditions: (a) assigning dominant and nondominant eye to distance and near, respectively, and (b) vice versa. The results revealed that through-focus visual acuity was unaffected by ocular dominance. Contrast sensitivity, however, was significantly improved when the dominant eye coincided with superior optical quality. We hypothesize that a potential mechanism behind this observation is an interaction between ocular dominance and binocular contrast summation, and thus, assignment of the dominant eye to distance or near may be an important factor to optimize contrast threshold performance at different object distances in both modified and traditional monovision.

Does direction of walking impact binocular rivalry between competing patterns of optic flow?

“…We surmise that this slight bias toward left-eye dominance might be related to the disparity in mean luminance between left-and right-eye LCOS displays, discovered after the fact. Three earlier rivalry studies reporting eye dominance results did not observe this trend toward left-eye dominance (Ooi & He, 2001;Al-Dossari et al, 2015;Zheleznyak et al, 2015).…”

Individual differences in sensory eye dominance reflected in the dynamics of binocular rivalry

“…Such tests are tapping into sensory-motor aspects of vision; they are not purely sensory in nature. Still, some previous studies using extended binocular rivalry tracking have found a link between sighting eye dominance and SED (Bosten, Goodbourn, Lawrance-Own, Bargary, Hogg & Mollon, 2015, Handa et al, 2004, Porac & Coren, 1978, Zheleznyak et al, 2015). However, we found no such relationship between measures in our data (Fig.…”

“…To account for all possible means through which a dominant eye might gain disproportionate predominance (see Fig. 1), and for the sake of consistency with previous studies that measured SED in prolonged binocular rivalry tracking blocks (Handa et al, 2004, Porac & Coren, 1978, Zheleznyak et al, 2015), we compared various aspects of rivalry dynamics to a metric of SED based on overall differences in predominance between the LE and RE (see 2.5 Data Analysis ). This metric (which we call SED) ranges from −100% (complete LE predominance) to +100% (complete RE predominance), and reflects the difference in the proportion of exclusive visibility of the RE and LE.…”

“…One can systematically manipulate the contrast or the luminance of the stimulus viewed by the disadvantaged eye to achieve equal predominance during rivalry, thus acquiring a quantitative metric of sensory eye dominance (SED; Ooi & He, 2001). This metric is predictive of binocular visual performance in a stereoacuity task (Xu, He & Ooi, 2011), and, when used to determine eye assignment for monovision correction (i.e., purposefully imbalanced refractive correction of the two eyes allowing distance vision by one eye and near vision for the other, sometimes favored by presbyopes or by patients following cataract surgery), this information can help improve binocular contrast sensitivity (Zheleznyak, Alarcon, Dieter, Tadin & Yoon, 2015). …”

“…Such methods target onset rivalry, a brief period of time (~1 second) following the initial presentation of dichoptic stimuli that is characterized by an increased influence of factors such as attention and color on rivalry predominance (Carter & Cavanagh, 2007, Mitchell, Stoner & Reynolds, 2004, Stanley, Forte, Cavanagh & Carter, 2011). Others have focused on the overall predominance of one eye across an extended binocular rivalry-tracking period (Handa et al, 2004, Porac & Coren, 1978, Zheleznyak et al, 2015). Importantly, there are a variety of ways that binocular rivalry dynamics could be altered that would yield a larger proportion of viewing time for one eye during an extended tracking block.…”