Chromatic discrimination: differential contributions from two adapting fields

Chromatic discrimination: differential contributions from two adapting fields.

To test whether a retinal or cortical mechanism sums contributions from two adapting fields to chromatic discrimination, L/M discrimination was measured with a test annulus surrounded by an inner circular field and an outer rectangular field. A retinal summation mechanism predicted that the discrimination pattern would not change with a change in the fixation location. Therefore, the fixation w...

Adapting Rabin's Theorem for Differential Fields

Harrington extended the first half of Rabin’s Theorem to differential fields, proving that every computable differential field can be viewed as a computably enumerable subfield of a computable presentation of its differential closure. For fields F , the second half of Rabin’s Theorem says that this subfield is Turing-equivalent to the set of irreducible polynomials in F [X]. We investigate poss...

The symmetry of visual fields in chromatic discrimination.

Both classical and recent reports suggest a right-hemisphere superiority for color discrimination. Testing highly-trained normal subjects and taking care to eliminate asymmetries from the testing situation, we found no significant differences between left and right hemifields or between upper and lower hemifields. This was the case for both of the cardinal axes of color space. In addition, ther...

S-cone discrimination in the presence of two adapting fields: data and model.

This study investigated S-cone discrimination using a test annulus surrounded by an inner and outer adapting field with systematic manipulation of the adapting l=L/(L+M) or s=S/(L+M) chromaticities. The results showed that different adapting l chromaticities altered S-cone discrimination for a high adapting s chromaticity due to parvocellular input to the koniocellular pathway. In addition, S-c...

Chromatic detection and discrimination