Abstract
Tests of additivity of the postreceptoral pathways that mediate the perception of blackness were conducted under conditions of spatial contrast. Observers increased the radiance of a surrounding annulus until a broadband (white) test center appeared completely black. Additivity tests with heterochromatic flicker photometry (HFP) and direct brightness matching were also conducted for each observer. The results indicated that the luminance level of the annulus required to induce blackness did not change with variations in spectral composition. Results consistent with additivity were also obtained for HFP, but the results from brightness matching were not consistent with additivity. The data support the view that the perception of blackness is mediated by neural mechanisms that additively combine the input of middle- and long-wave photoreceptors.
Highlights
Tests of additivity of the postreceptoral pathways that mediate the perception ofblackness wereconducted under conditions of spatial contrast
In one set of studies, 2 3 using a response criterion of complete blackness, the spectral efficiencywas found to resemble the overall shape of the photopic luminosity function of the standard observer and individual observers' heterochromatic flicker photometry (HFP) functions
Additivity has been investigated with temporally induced blackness,[8] and the results indicate that blackness induction, like HFP, shows no failures of additivity
Summary
Tests of additivity of the postreceptoral pathways that mediate the perception ofblackness wereconducted under conditions of spatial contrast. Except the 4-Td intensity series ofLA, the illuminances of the broadband standards in HFP and brightness matching were equated to the mean illuminance required to induce blackness at 550 nm with a 2Td test center.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
