@article{Stockman2005_0,<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Abstract = {The luminance pathway has slow (s), spectrally opponent cone inputs in addition to the expected fast (f), non-opponent inputs. The nature of these inputs to luminance flicker perception was further explored psychophysically by measuring middle- (M-) and long-wavelength-sensitive (L-) cone modulation sensitivities, M- and L-cone phase delays, and flicker spectral sensitivities under three conditions of low to moderate long-wavelength adaptation. Under these conditions we find that the luminance channel has fast M- and L-cone input signals (+fM and +fL), and slow, spectrally opponent cone input signals (+sL and –sM). The slow signals found under these conditions are therefore of the opposite polarity to those (+sM and –sL) found under more intense long-wavelength adaptation. At these less intense levels, fast and slow M-cone signals of opposite polarity (–sM and +fM) cancel at low frequencies, but then constructively interfere at intermediate frequencies (ca 12.5–22.5 Hz, depending on adapting level) because of the delay between them. In contrast, fast and slow L-cone signals of the same polarity (+sL and +fL) sum at low frequencies, but then destructively interfere at intermediate frequencies. Importantly, the spectrally opponent signals (+sL and –sM) contribute to flicker nulls without producing visible colour variation. Although its output generates an achromatic percept, the luminance channel has slow spectrally opponent as well as fast non-opponent inputs.},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Author = {Andrew Stockman and Daniel J.  Plummer and Ethan D.  Montag},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Journal = {Journal of Physiology},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Keywords = {human luminance pathway},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Month = {},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Number = {},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pages = {61--76},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Title = {Spectrally-opponent inputs to the human luminance pathway (I): slow +M and -L inputs revealed by intense long-wavelength adaptation},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Url = {},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Volume = {566},<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Year = {2005}