Week 4 Vision Objective 3 Flashcards
Layers of Retina (5)
Photoreceptor cells Horizontal cells Bipolar cells Amacrine cells Ganglion cells
- Photoreceptors
- rods and cones 2. synapse with horizontal and bipolar cells 3. send signals to outer plexiform layer (layer of synaptic connections)
- Horizontal cells
Transmits signals from rods/cones to bipolar cells 2. transmits signal to outer plexiform layer 3. output ALWAYS inhibitory (lateral inhibition)
- Bipolar cells
- transmits signals from rods, cones, horizontal cells TO inner plexiform layer 2. synapses with amacrine and ganglion cells
- Amacrine cells
- Transmits signals directly from bipolar to ganglion cells 2. Transmits within inner plexiform layer FROM axons of bipolar cells to dendrites of ganglion cells or to other amacrine cells
- Ganglion cells
- transmits signals from the retina to the brain 2. axons make up the optic nerve 3. ONLY RETINA CELLS THAT GENERATE AN ACTION SIGNAL 4. All the others use electrotonic conduction
Interplexiform cells
Transmits signals from inner plexiform to outer plexiform later inhibitory signals lateral inhibition
Fovea Region nervous circuitry
has three cells
- cones
- bipolar cells
- ganglion cells
Foveal region vs pure rod region
foveal has cone, rod, and bipolar cells
pure rod vision has four neurons: rods, bipolars, amacrine and ganglion cells
Rods/cones synapse with bipolar cells they use
glutamate
amacrine cells use what transmitters?
eight or more, so most of them, and all inhibitory