Mid-frequency loss of foveal flicker sensitivity in early stages of age-related maculopathy.
Temporal contrast sensitivity in eyes at risk for exudative age-related maculopathy (ARM) was compared to that in age-matched healthy older eyes. The test stimulus was a foveally viewed, flickering, long-wavelength 2.8 degrees diameter circle in an equiluminant (photopic) surround. Retinal illuminance and decision criterion differences were experimentally controlled. Eyes in the healthy and ARM-risk groups had 20/30 or better Snellen acuity and intraocular pressure of less than 22 mmHg. Nevertheless, the ARM-risk patients were less sensitive to flicker contrast, especially for mid-temporal frequencies. This suggests that flicker sensitivity may be useful in identifying patients at risk for exudative ARM. In addition, comparison with other research reveals a paradox: Mid-temporal frequency sensitivity losses may be attributable primarily to a "high temporal frequency" mechanism.
Mayer
M J
MJ
Program in Experimental Psychology, University of California, Santa Cruz 95064.
Spiegler
S J
SJ
Ward
B
B
Glucs
A
A
Kim
C B
CB
D000368:Aged; D000369:Aged, 80 and over; D015350:Contrast Sensitivity; D005260:Female; D005425:Flicker Fusion; D005584:Fovea Centralis / Q000503:physiopathology*; D006801:Humans; D007429:Intraocular Pressure; D008268:Macular Degeneration / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014786:Vision Disorders / Q000503:physiopathology*; D014792:Visual Acuity