Some temporal output properties of color opponent units in the ground squirrel retina

Responses of BG-G units to equal energy stimuli of different wavelengths reveal a tonic to phasic pattern of responses in which short wavelengths (blue) evoke tonic activity, medium wavelengths (green to yellow) evoke phasic activity and intermediate wavelengths evoke in-between patterns. The patterns correlate with wavelength but are relatively insensitive to intensity. Output patterns of BG-G cells to white and to monochromatic light at the animal's neutral point are almost identical, and the pattern identities may be a neural correlate to the behavioral phenomenon of the neutral point.