Which retinal layer contains the synapses between photoreceptors and bipolar/horizontal cells?

Which retinal layer contains the synapses between photoreceptors and bipolar/horizontal cells?

• A. Inner Plexiform Layer
• B. Outer Plexiform Layer
• C. Nerve Fiber Layer
• D. Ganglion Cell Layer

Answer: (B)

The synapses between photoreceptors and the next neurons occur in the outer plexiform layer. Here, rod spherules and cone pedicles connect with the dendrites of bipolar cells and with horizontal cells, enabling both direct signal transmission to bipolar cells and lateral modulation by horizontal cells. This layer sits between the photoreceptor cell bodies and the inner retinal layers, setting up the flow of information: photoreceptors to bipolar/horizontal cells in the outer plexiform layer, then to ganglion and amacrine cells in the inner plexiform layer, and finally along the nerve fiber layer to the optic nerve.

The synapses between photoreceptors and the next neurons occur in the outer plexiform layer. Here, rod spherules and cone pedicles connect with the dendrites of bipolar cells and with horizontal cells, enabling both direct signal transmission to bipolar cells and lateral modulation by horizontal cells. This layer sits between the photoreceptor cell bodies and the inner retinal layers, setting up the flow of information: photoreceptors to bipolar/horizontal cells in the outer plexiform layer, then to ganglion and amacrine cells in the inner plexiform layer, and finally along the nerve fiber layer to the optic nerve.