Central motion perception, as assessed by minimum displacement detection, was reduced in highly myopic eyes. Peripheral motion detection may be influenced by myopia, particularly in the inferior-nasal retina.
Motion discrimination is a complex visual task processed mainly via the magnocellular pathway. We investigated whether it is affected in myopia.
Ninety young adults aged 18 to 28 years participated: 30 emmetropes (spherical equivalent refractions +1.00 to −0.50 diopters [D]), 30 low myopes −1.00 to −4.75 D) and 30 higher myopes (<−5 D). Random dot patterns were used to measure motion perception thresholds for minimum displacement (D min), maximum displacement (D max), and motion coherence tasks. Each task was performed centrally and at four oblique peripheral visual field locations (at 3.65 and 12 degrees for D min and D max tasks, respectively). Macular retinal thickness was measured with optical coherence tomography.
The central D min task was correlated significantly with refraction (r = −0.303, P = .004) and axial length (r = +0.224, P = .04), and the superior-temporal field D min task was correlated significantly with axial length (r = 0.230, P = .04). Higher myopes had poorer performance than emmetropes by 25% (higher values). For the D min peripheral task and for D max and coherence tasks at both central and peripheral locations, there were no significant correlations with refraction or axial length. At three of four positions, the peripheral D min task was correlated significantly with thickness in the corresponding retinal region: superior-temporal D min (Pearson r = −0.357, P < .001), inferior-nasal D min (r = −0.237, P = .03) and inferior-temporal D min (r = −0.233, P = .03).
Central motion perception, as assessed by minimum displacement detection, was reduced by 25% in highly myopic eyes. Peripheral motion detection may be influenced by myopia, particularly in the inferior-nasal retina. Retinal stretching due to axial elongation may be linked to reduced performance in higher myopes.
1School of Optometry & Vision Science, Faculty of Health, and Institute of Health & Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia
2School of Optometry, Chung Shan Medical University Hospital, Taichung City, Taiwan
3Department of Ophthalmology, Chung Shan Medical University Hospital, Taichung City, Taiwanfirstname.lastname@example.org
Submitted: March 2, 2017
Accepted: April 2, 2018
Funding/Support: None of the authors have reported funding/support.
Conflict of Interest Disclosure: No conflicts of interest.
Author Contributions: Conceptualization: DAA, KLS; Methodology: H-YK, DAA, KLS; Supervision: DAA, KLS; Writing – Original Draft: H-YK, DAA, KLS; Writing – Review & Editing: H-YK, H-YK, DAA, KLS.