The effects of optical blur on motion and texture perception.
OBJECTIVE
The purpose of this study is to determine how decreased visual acuity affects performance on tasks of motion and texture perception.


METHODS
Positive diopter lenses were used to match three subjects at five levels of decimal visual acuity (DVA) ranging from an uncorrected DVA of 1.6 to the lowest DVA of 0.2. Performance thresholds were determined at each acuity level for five different psychophysical tasks. The tasks assessed the perception of motion-defined form, global motion, maximum motion displacement (Dmax), texture-defined form, and global texture.


RESULTS
Reducing visual acuity decreased performance on the tasks of motion-defined form identification, texture-defined form identification, and global texture integration. Performance on the Dmax task improved with a reduction in visual acuity. Performance on the global motion task was unaffected by changes in visual acuity.


CONCLUSIONS
Visual acuity should be considered when interpreting the results of developmental or clinical studies of motion and texture perception. The only exception to this is global motion perception, at least when DVA is better than 0.2. The effect of blur on tasks of motion and texture perception may reflect the extent to which high spatial frequency information is required for performance on these tasks.
Zwicker
Amy E
AE
Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
Hoag
Ryan A
RA
Edwards
Veronica T
VT
Boden
Catherine
C
Giaschi
Deborah E
DE
D006801:Humans; D009039:Motion Perception / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012720:Severity of Illness Index; D015354:Vision, Low / Q000503:physiopathology*; D014792:Visual Acuity