You have a photoreceptor that might itself somehow contribute to colour perception but alone is not colour-sensitive 9,98-. 9083,8. The problem of univariance is the fact that an infinite set of different wavelengthintensity combinations can elicit exactly the same response from a single type of photoreceptor. One photoreceptor type cannot make accurate color discriminations based on wavelength. The solution 89,90;024709,3430. 44:7-sensitive photoreceptor like red, green and blue cones in our retinas. The combinations of the outputs of these three types of cones ,. 9:,90:8,9. 44:78070443,9. The location of objects whose images lie on corresponding points. 988,3,70,0700/439,;0double vision when we converge our eyes on something. The relationship between arousal & attention as arousal increases, the attention increases but further increases in arousal could also bring about decreased attention. Attention can be directed at inputs, thoughts & actions. Able to process them & ignore other things. Too much arousal seems to activate all sorts of sensory inputs in a global way.