Density of human cone photopigments as a function of age.

نویسندگان

  • D van Norren
  • G J van Meel
چکیده

The density difference between fully bleached and fully dark-adapted retinas was assessed for 77 eyes (47 subjects) in the age group 13-50 yr. No significant change in density was found as a function of age. The time constant of pigment regeneration was also found to show no age effects up to the age of 50 yr. These findings are at odds with another study on the density of foveal cones.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Aging and human cone photopigments.

We used a noninvasive technique to investigate changes in photoreceptor function with aging in observers 13-69 years of age. This technique, steady-state color matching, provides estimates of the optical density of cone photopigments, the illuminance that bleaches half of the photopigment, and the ratio of the primaries required at moderate light levels. In normal human retinas, we found that t...

متن کامل

A psychophysical technique for measuring cone photopigment bleaching.

A new, clinically applicable test has been developed to measure the bleaching of the foveal cone photopigments. This noninvasive test is called steady-state color matching. Steady-state color matching is based on the dependence of a color match on the optical density of the cone photopigments. By measuring the color match as a function of retinal illuminance, it is possible to compute the optic...

متن کامل

Opsin genes, cone photopigments, color vision, and color blindness

In this chapter, we introduce the molecular structure of the genes encoding the human cone photopigments and their expression in photoreceptor cells. We also consider the consequences that alterations in those genes have on the spectral sensitivity of the photopigments, the cone photoreceptor mosaic, and the perceptual worlds of the color normal and color blind individuals who possess them. Thr...

متن کامل

Macular pigment, photopigments, and melanin: Distributions in young subjects determined by four-wavelength reflectometry

We have developed an objective procedure, using a modified retinal camera, to determine macular pigment (MP) optical density distributions in the human retina. Using two multi-band filters, reflectance maps of the retinas of young subjects (<25 years old) were obtained at 460, 528, 610 and 670 nm, without pupil dilation. The log-transformed maps were combined linearly to yield optical density m...

متن کامل

Modeling Trichromatic Color Appearance with Only Two Spectrally Distinct Photopigments

Protanomaly is a common abnormality of color vision in which the long wavelength sensitive cone is lacking. Protanomalous observers are trichromatic with reduced ability to discriminate colors in the red-green part of the spectrum because the photopigments that mediate discrimination in this range are abnormally similar differing in one of two ways; first, by only a few nanometers in peak sensi...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Investigative ophthalmology & visual science

دوره 26 7  شماره 

صفحات  -

تاریخ انتشار 1985