Differential effects of aging on spatial contrast sensitivity to linear and polar sine-wave gratings
Braz. j. med. biol. res
;
46(10): 855-860, 24/set. 2013. graf
Artículo
en Inglés
| LILACS
| ID: lil-688555
ABSTRACT
Changes in visual function beyond high-contrast acuity are known to take place during normal aging. We determined whether sensitivity to linear sine-wave gratings and to an elementary stimulus preferentially processed in extrastriate areas could be distinctively affected by aging. We measured spatial contrast sensitivity twice for concentric polar (Bessel) and vertical linear gratings of 0.6, 2.5, 5, and 20 cycles per degree (cpd) in two age groups (20-30 and 60-70 years). All participants were free of identifiable ocular disease and had normal or corrected-to-normal visual acuity. Participants were more sensitive to Cartesian than to polar gratings in all frequencies tested, and the younger adult group was more sensitive to all stimuli tested. Significant differences between sensitivities of the two groups were found for linear (only 20 cpd; P<0.01) and polar gratings (all frequencies tested; P<0.01). The young adult group was significantly more sensitive to linear than to circular gratings in the 20 cpd frequency. The older adult group was significantly more sensitive to linear than to circular gratings in all spatial frequencies, except in the 20 cpd frequency. The results suggest that sensitivity to the two kinds of stimuli is affected differently by aging. We suggest that neural changes in the aging brain are important determinants of this difference and discuss the results according to current models of human aging.
Texto completo:
Disponible
Índice:
LILACS (Américas)
Asunto principal:
Estimulación Luminosa
/
Envejecimiento
/
Sensibilidad de Contraste
Tipo de estudio:
Estudio diagnóstico
Límite:
Adulto
/
Anciano
/
Femenino
/
Humanos
/
Masculino
Idioma:
Inglés
Revista:
Braz. j. med. biol. res
Asunto de la revista:
Biologia
/
Medicina
Año:
2013
Tipo del documento:
Artículo
País de afiliación:
Brasil
Institución/País de afiliación:
Universidade de Sao Paulo/BR
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