Abstract
Purpose: :
To study dynamic visual perception and determine whether myopes and emmetropes may have different performances.
Methods: :
Seventeen subjects participated in the experiment: 9 myopes (-0.75D to -5.25D; mean refractive error -2.19±1.44D) and 8 emmetropes (plano to +1.00D; mean refractive error +0.11±0.31D). Two tasks of "dynamic visual perception" were implemented. Motion sensitivity was determined using random dot kinematogram (RDK) stimuli. The other task involved recognition of saccadic moving letters. Size of letters was adapted to subject’s responses following a staircase procedure. This second task allowed us to determine what we have called "the dynamic visual acuity", for each subject.
Results: :
Motion sensitivity thresholds were lower for myopes compared to emmetropes (Anova, F[1;15]=6.72; p=0.0204). Furthermore, Myopes had better dynamic visual acuity than emmetropes. This difference was close to significance (Anova, F[1;15]=3,91; p=0.0665).
Conclusions: :
Both dynamic visual tasks involved in the present study showed that myopes were more efficient than emmetropes. Differences in exposure to blur during development may be one of the sources of these differences.
Keywords: myopia • motion-2D • visual acuity