The contribution of blue-sensitive cones to spatial responses of post-receptoral visual channels in man.
Psychophysical methods developed for the investigation of spatial and temporal pathways in human vision have been applied in combination with the two-colour increment threshold technique of W. S. Stiles to study the way in which signals from blue-sensitive cones are transmitted along the visual pathways. A flicker sensitive spatio-temporal filter, designated 'ST2', has been examined by background modulation methods, and spatial filters sensitive to bars of a specific width by grating adaptation methods employing dichoptic presentation of stimuli. It is shown that the blue-sensitive (pi 3) spectral mechanism contributes to both classes of filter response, in a manner similar to that observed for the red-sensitive spectral mechanism. The binocularly driven, bar-sensitive filters have broad-band spectral response characteristics, thus the data demonstrate that signals arising in blue-sensitive cones converge onto a luminance channel. The results of this investigation, together with those previously published for a second (ST1) spatio-temporal filter, describe a variety of post-receptoral responses involving the pi 3 spectral mechanism.
Blythe
I M
IM
Department of Physics (Biophysics), Imperial College, London, UK.
Bromley
J M
JM
Holliday
I E
IE
Ruddock
K H
KH
D003118:Color Perception / Q000502:physiology*; D006801:Humans; D010786:Photoreceptor Cells / Q000502:physiology*; D011601:Psychophysics; D013028:Space Perception / Q000502:physiology*; D014795:Visual Pathways