Jay M. Enoch

Performance on three-point vernier acuity targets as a function of age.

With certain (but not all) vernier acuity (VeA) stimulus displays observers exhibit no or slight performance decrements with aging. Because three-point VeA test displays are much more easily applied experimentally and clinically, we examined visual performance on this task as a function of age. Ages of groups tested ranged from 20 to 70+ years (some individuals were 90+ years old). Eyes were examined monocularly. We tested three- and two-point sharply defined VeA arrays and a three-point ground-glass-degraded display (simulating a 20/100 nuclear cataract). Gap or feature separations were varied. Results obtained with the three-point display showed little alteration with age. Image degradation resulted in reduction in performance when small gap separations were used between the test points, but only slight decrements for large gap separations were recorded. The finding that performance with certain VeA targets is largely unaffected by age is confirmed and is expanded.

Clinical Visual Psychophysics Measurements

Unfortunately, a gap often exists between the work of the research psychophysicist, who develops perceptual tests in the academic setting, and the clinician, who faces the often complex task of evaluating the capabilities and characteristics of a given sensory test on a patient. Important questions then are How does the basic scientist translate the paradigms of his or her sensory research to the clinical setting? and How does the clinician utilize the current theoretical and laboratory research in his or her diagnostic examination and use that knowledge to help understand patient data? Noninvasive psychophysical tests supply one answer and are in use as both research tools and diagnostic aids. These tests provide rapid, reliable, valid data with minimal discomfort to the patient.