08 Cone & Rod Circuits Flashcards
what type of feedback do horizontal cells provide to cones?
negative feedback (inhibitory)
bipolar cells are considered on or off cells. what cells communicate if less light is being detected?
off cells
29 What type of system is used by retinal ganglion cells to detect light?
centers-surrounds
29 What are the three types of signals that can be generated using the centers-surrounds system?
- On2. Off3. On-Off (intermediate or summation of on and off)
30 What type of response would be generated if just the center of the receptive field was stimulated by light?
An “on” response
30 What can the centers-surrounds system detect?
Contrast edges (contrast borders)
32 What defines the ganglion cell’s contrast sensitivity?
The size of it’s receptive field
33 When referring to how ganglion cells respond to stimulus, midget cells are _____ and parasol cells are _______.
tonic, phasic
33 What does a tonic response tell the brain?
How big of a change in light stimulus there was
33 What does a phasic response tell the brain?
How things (light) are moving around in space (on the retina)
what type of bipolar cell uses metabotropic channels?
bipolar on cells
do bipolar off cells have metabotropic or ionotropic channels?
ionotropic channels
is the on-sublayer closer to the peducle of the cone?
no. the off-sublayer is
which type of cell will create a hyperpolarizing signal?
the off cell
what type of neurotransmitter do amacrine cells use?
glycine and GABA
do rods have a larger synaptic terminal than a cone?
no. rods have a small synaptic terminal compared to cones
02 What is the neurotransmitter released from the synaptic terminal?
Glutamate
02 Which cells defines if there is a decrease/increase in photons?
Bipolar cells
03 Cell begin to _______ as it catches more photons, causes _______ in releasing of glutamate.
hyperpolarize, decrease
04 An ______ in photons causes a ______ in glumate release
increase, decrease
05 Each cone contacts 100’s of _____ and _____ cells.
bipolar and horizontal cells
05 In the synaptic terminal, glutamate binds on ______ and released in vesicle.
synaptic riboon
06 Horizontal section of cone pedicle have about 40 ________
synaptic ribbons
07 Both sides of each ribbon is flanked by which cells?
horizontal cells.
08 What do bipolar cells do?
Complete the triad of connections and also get good information about changes in glutamate released
09 In horizontal section of each cone pedicle, processes are packed _____ to each other.
Very densely
19 - Which types of cells do rods contact?
Only H1 cells and Rod bipolar cells
19 - Each H1 cells contacts about how many rods at a time?
About 700 rods at a time
19 - T/F Each rod communicates with at least 2 horizontal cells in order to spread the signal to both sides of the periphery of where thatrod is located.
true
20 - T/F All rod bipolar cells are “on-cells”.
true
21 - What type of amacrine cells connect rods to bipolar cone cells in order to communicate?
all (A2)
22 - Because of the sensitivity of rods - they produce a signal that is _________ times stronger than a cone.
100 times
24 - What are the four types of ganglion cells?
1) Parasol ganglion cells2) Midget ganglion cells3) Blue-yellow ganglion cells4) Biplexiform ganglion cells
24 - 95% of the fovea will contain which type of ganglion cell?
Midget ganglion cells
24 - Blue-yellow ganglion cells communicate with which type of cones?
S-cones
25 - What does the neural signal depend on?
Changes in firing rate
26 - What types of responses do ganglion cells have?
On- and Off- responses
