PSYC 212 Lecture Notes - Lecture 5: Amacrine Cell, Retina Horizontal Cell, Receptive Field

• School: McGill University
• Department: Psychology
• Course: PSYC 212
• Professor: Mathieu Roy

Document Summary

Light transduction in the retina is a little bit odd. Instead of depolarizing when activated, it will hyperpolarize. The only that it can communicate with the other nearby cell is to send a graded potential to the bipolar cell. if it is an on bipolar cell it will reverse the sign of the potential. Receptive field: region on the retina in which the stimuli influence a neuron"s firing rate: receptive fields have a center-surround organization (on/off or off/on, this allows to increase contrast, this organization depends on horizontal cells. In the retina, we have a vertical system and a lateral system comprised of the horizontal cells and the amacrine cells: the horizontal cells allow for that center-surround organization. Light negative , dark positive: the positive sign will activate the horizontal cells which in turn inhibit all the cones (photoreceptors). Because the center cone is places in the middle of 2 horizontal cells, it receives more inhibition that surround cones.