Adaptation (eye) opsin photopigment. The various cone cells are maximally sensitive to either short wavelengths (blue light), medium wavelengths (green light), or long wavelengths (red light). Rod photoreceptors only contain one type of photopigment, rhodopsin, which has a peak sensitivity at a wavelength of approximately 530 nanometers which corresponds to blue-green light. A minor mechanism of adaptation is the pupillary light reflex, adjusting the amount of light that reaches the retina. In response to varying ambient light levels, rods and cones of eye function both in isolation and in tandem to adjust the visual system. Changes in the sensitivity of rods and
Retina horizontal cell However, when recordings are made from parts of the cone that are distant from the cone terminals that synapse onto bipolar cells, center-surround antagonism seems to be less reliable in cones than in bipolar cells. As the invaginating synapses from horizontal cells are made onto cone terminals, the center-surround antagonism of cones is thought to be more reliably present in cone terminals. Retina horizontal cell Horizontal cells are the laterally interconnecting neurons having cell bodies in the inner nuclear layer of the retina of vertebrate eyes. They help integrate and regulate the input from multiple photoreceptor cells. Among their functions,