Color discrimination at threshold: the approach through increment threshold sensitivity.

نویسنده

  • D B Kirk
چکیده

A close correlation between Stiles's increment threshold (pi-mechanism) approach and color discrimination at threshold was found: a sharp transition from detection of two lights via two pi-mechanisms (pi 1 and pi 4) to detection via only one pi-mechanism (pi 1) was paralleled by a sharp decline from excellent discrimination between those two lights (even with the rods bleached) to no discrimination. This parallel between detection and discrimination suggests that Stiles's approach can isolate single visual pathways with distinct perceptual correlates.

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

Color vision sensitivity in normally dichromatic species and humans.

Spectral-sensitivity functions for large, long-duration increments presented on a photopic white background indicate that wavelength-opponent mechanisms mediate detection in both normal and dichromatic humans. Normal humans exhibit high color-vision sensitivity as they discriminate the color of spectral flashes at detection-threshold intensities. However, dichromatic humans require stimuli up t...

متن کامل

Increment threshold and purity discrimination spectral sensitivities of X-chromosome-linked color-defective observers

The goal of the study was to evaluate spectral opponency in nine X-chromosome-linked color-defective observers. The tasks included increment threshold spectral sensitivity on an achromatic background, heterochromatic flicker photometry, and colorimetric purity discrimination. With a task of heterochromatic flicker photometry, the anomalous trichromatic observers showed spectral sensitivity of t...

متن کامل

Traumatically acquired color vision defect.

A 24-year-old man acquired a color vision defect shortly after an accident in which he struck the back of his head. Results of the Farnsworth-Munsell 100-hue test showed that the patient had poor color discrimination in both eyes. His color matches on the Nagel anomaloscope suggested a red/green disturbance. Results from increment threshold testing demonstrated on absence of the blue mechanism....

متن کامل

WAVELENGTH AUTOMATED PERIMETRY ( SWAP ) Chris

The pioneering work of Stiles provided a means of psychophysically isolating and measuring the sensitivity of individual color vision mechanisms through the two-color increment threshold procedure. Basically, this approach involved decreasing the sensitivity of some color vision mechanisms (termed π mechanisms by Stiles) by using a chromatic adapting background light, and then measuring the sen...

متن کامل

Mechanisms underlying the detection of increments in parafoveal retina

It is well established that the spectral sensitivity under photopic conditions varies across the human retina. We investigate the mechanisms underlying these spectral changes. Through the use of color appearance, flicker sensitivity, additivity, discrimination at threshold and modeling, we show that the changes in spectral sensitivity on a photopic white background across parafoveal retina are ...

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:
  • Vision research

دوره 22 7  شماره 

صفحات  -

تاریخ انتشار 1982