 OFF retinal bipolar cell

An OFF retinal bipolar cell is a retinal bipolar cell whose central receptive response shows depolarization for an appropriate decrease in illumination. Its input synapse preserves the sign of a cone photoreceptor's voltage response through excitatory AMPA receptors or kainate receptors, rather than the sign-inverting arrangement of an ON retinal bipolar cell.^[ref]

In a 2000 experiment, simultaneous recordings from connected cone cells and OFF retinal bipolar cells, together with receptor-selective manipulations, distinguished receptor mechanisms in different morphological OFF types. Differences in recovery from receptor desensitization filtered the same cone signal into different temporal components.^[ref]

Thus two OFF types can agree on whether a light decrement excites them while differing in response timing. Response sign, temporal filtering and neuron identity are related measurements, not interchangeable labels. The result from the studied retina should not be taken as an identical receptor assignment for every OFF subtype in every species.