Abstract

SANTOS, Natanael Antonio dos; SIMAS, Maria Lúcia de Bustamante  and  NOGUEIRA, Renata Maria Toscano Barreto Lyra. Visual processing of form in the aged: threshold contrast curves to angular and spatial frequency. Psicol. Reflex. Crit. [online]. 2003, vol.16, n.2, pp. 271-277. ISSN 0102-7972.  http://dx.doi.org/10.1590/S0102-79722003000200007.

The aim of this work was to measure contrast sensitivity curves for angular and spatial frequencies in the aged. We measured the contrast thresholds from young adults (20-26 years-old) and aged (60-67 years-old). All the participants had good visual acuity and were free from significant ocular pathology. The angular and spatial frequencies measured with a forced-choice psychophysic method were 2, 4, 8, 16, 24, 32, 48, 64 and 96 cycle/360º and 0.5, 1, 2, 3, 4, 6 and 9 cpd, respectively. The results showed a loss in contrast sensitivity for the aged at high and medium angular and spatial frequencies compared to the younger group. We still found that the contrast sensitivity of the aged group at low angular frequency is better than the younger group. These results are consistent with age-related changes in contrast sensitivity function.

Keywords : Visual processing of form; angular frequency; spatial frequency; contrast sensitivity; forced-choice method.