Fixation disparity and accommodation for stimuli closer and more distant than oculomotor tonic positions

Jaschinski, Wolfgang

doi:10.1016/s0042-6989(00)00322-9

Cited by 40 publications

(49 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We assume that fixation disparity measures are physiologically plausible if they are correlated with dark vergence (at least at a viewing distance of 100 cm, which is close to the population mean of dark vergence). Like in a previous study, 29 we found that subjects tended to have an eso or exo fixation disparity if the viewing distance corresponding to dark vergence was closer or more distant than the test distance of fixation disparity (100 cm). This correlation with dark vergence was observed at all gaps with continuous nonius lines and at 1.0-and 3.3-deg gaps with flashed nonius lines.…”

Section: Discussionsupporting

confidence: 85%

See 1 more Smart Citation

Horizontal Fixation Disparity Measures With Nonius Lines

Jaschinski

Kloke²,

Jainta³

et al. 2005

Optometry and Vision Science

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Discussionsupporting

confidence: 85%

“…28 The individual nonius bias can amount to a few minutes of arc (if nonius lines have a vertical gap) and may be a more appropriate reference of fixation disparity than the physical coincidence of nonius lines. 29 Thus, our analyses also include the corrected fixation disparity, i.e., the fixation disparity minus nonius bias.…”

mentioning

confidence: 99%

Horizontal Fixation Disparity Measures With Nonius Lines

Jaschinski

Kloke²,

Jainta³

et al. 2005

Optometry and Vision Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…By contrast, when watching the moon high in an empty sky in the relative absence of contextual information, the vergence system will remain in resting posture (right panel of Figure 3). As a result, the eyes will be severely overconverged, resulting in larger fixation disparity (Jaschinski, 2001;Jaschinski et al, 1998).…”

Section: Kimmentioning

confidence: 99%

Oculomotor Effects in the Size-Distance Paradox and the Moon Illusion

Kim

2012

Ecological Psychology

View full text Add to dashboard Cite

Drawing on 2 concepts-the resting position of the eyes and a binocular geometry for perceived size, the moon illusion is explained as the consequence of different oculomotor adjustments caused by change in the direction of gaze contingent upon the viewing conditions of the moon. Hence, each particular moon will be viewed with a different vergence state which, in turn, yields a different amount of binocular disparity. The vergence state will determine the perceived size of an object whereas disparity will determine its perceived distance. It is further contended that the perceived size of the moon is based on a new binocular information source for size perception enabling the size of an object to be perceived even in the absence of egocentric distance information. Discussion focuses on the paradoxical aspect of the moon illusion and how the size-distance invariance hypothesis may have contributed to its effect.People observing the moon commonly report that it appears larger and closer when it is near the horizon than when it is higher in the sky. This phenomenon arises despite the fact that the moon itself remains constant revolving around the earth at a distance of about 245,000 miles 1 with a fixed diameter of 2,200 1 Because the moon orbits the earth along an elliptical path, its distance from the earth changes, depending on its location in the orbit, from 363,104 km (225,622 miles) at its minimum to 405,696 km (252,088 miles) at its maximum. On average, the distance from the center of the earth to the center of the moon is approximately 384,403 km (238,857 miles).

show abstract

“…However, the more the accommodative response exceeds the dark focus level (A > DF), the larger the influence of accommodative vergence and-as a result-the more the dissociated phoria is shifted to a closer (i.e., more eso) position; the amount of this accommodative effect depends on the individual AC/A-ratio. Multiple regression analyses have shown that this model is able to explain about 50% of the inter-individual variability of the distant dissociated phoria (Owens & Tyrrell, 1992) and about 80% of the near dissociated phoria (Jaschinski, 2001).…”

Section: Dark Vergence Vs Dissociated Phoriamentioning

confidence: 99%

Resting Positions of Vergence and Their Relation to Asthenopic Complaints

Jaschinski¹,

Walper

2007

Strabismus

Self Cite

View full text Add to dashboard Cite

Dark vergence is a resting position of vergence, measured in a dark visual field to eliminate fusional, accommodative, and proximal stimuli. Dark vergence differs among subjects: the average subject converges to a viewing distance of about 1 m, while the inter-individual range is from infinity to about 40 cm. This paper reviews previous ergonomic studies on dark vergence in relation to asthenopic complaints that occur when working at near computer screens: subjects with distant dark vergence exert more convergence and experience stronger asthenopic complaints than subjects with near dark vergence. The dissociated phoria, a common clinical measure of resting vergence, is only weakly correlated with asthenopic complaints, probably because of accommodative influences that cause the difference between dark vergence and dissociated phoria.

show abstract

Fixation disparity and accommodation for stimuli closer and more distant than oculomotor tonic positions

Cited by 40 publications

References 23 publications

Horizontal Fixation Disparity Measures With Nonius Lines

Horizontal Fixation Disparity Measures With Nonius Lines

Oculomotor Effects in the Size-Distance Paradox and the Moon Illusion

Resting Positions of Vergence and Their Relation to Asthenopic Complaints

Contact Info

Product

Resources

About