Which retinal cells are horizontal
Horizontal, amacrine
Which retinal cells are vertical
Rods, cones, bipolar cells, ganglion cells
Spontaneous activity
Cells spontaneously generate action potentials in the absence of a spot of light
Whether a stimulus in the receptive field will either increase or decrease the firing rate of the neuron depends on _______
Location
A small light located within the center of a receptive field causes an ____ in the frequency of action potentials
Increase
A small light positioned in the surround of a receptive field causes a _____ in the frequency of action potentials
Reduction
If a larger spot of light fills the entire center of a receptive field, action potentials will fire at a _____ rate
Maximum
A ganglion cell response to a stimulus that fills the entire receptive field about the same as if ____
There were no stimulus
Spatially antagonistic ganglion cells do not respond well to ____ illumination
Diffuse
_____ are a strong stimulus for ganglion cells
Sine-wave gratings
As the diameter of the spot ______, the cell's firing rate increases until the entire receptive filed center is covered with light and the response is at its maximum
Increases
Firing will decreases as the diameter of the light exceeds that of the center of a receptive field because it falls on the inhibitory surround, which is _____ to the excitatory center
Antagonistic
When is the frequency of action potentials zero?
Never
What types of cells generate action potentials
Amacrine, ganglion
Cells which do not generate action potentials generate _____
Graded potentials
A spot and annulus elicit responses of ______ from the bipolar and ganglion cells because the spot falls on the receptive field center whereas the annulus falls on its antagonistic surround
Opposite signs
Photoreceptors respond to light with a ______ response
Slow hyperpolarizing
Rods detect dim light and respond to relatively _____ changes
Slow
Cones detect bright light and respond to ______ light fluctuations
Rapid
______ are the first synaptic level in the retina
Horizontal cells
______ receive input from many cones
Horizontal cells
Horizontal cells have a _____ receptor field and therefore respond to light over a large area
Large
Horizontal cells modulate the photoreceptor signal under _______, which allows the signaling to become less sensitive in bright light and more sensitive in dim light
Different lighting conditions
______ shape the receptive field of bipolar cells
Horizontal cells
H1 horizontal cells receive excitatory input from which type of cones
L and M cones
H2 horizontal cells receive excitatory input rom which type of cones
L, M, S cones
Which type of cone provides a particularly strong input to H2 horizontal cells
S cones
Bipolar cells receive input from a handful of cones and therefore have a ______ receptor filed
Medium size
______ add an opponent signal which gives bipolar cells its center and surround organization
Horizontal cells
Two types of amacrine cells
Small field, wide field
Small field cells spread vertically across _____ in the IPL
Several strata
Small field cells collect signal from about _____ rod-connected bipolar cells as bipolar cells
30
Small field amacrine cells link ______ and _____
Rod-connected bipolar cells, ganglion cells
Wide field cells stretch horizontal across the IPL but typically confine to _____
One strata
What type of cells sharpen the boundary between center and surround even further than H cells do
Amacrine cells
How many bipolar and ganglion cells do wide field cells interact with
100s
OFF center ganglion cells are _____ when a spot of light falls in the periphery of their receptive field
Activated
Ganglion cells in the fovea are connected to _____ in a one-to-one ratio
Bipolar cells
How is a point-to-point image relayed from fovea to brain
Info travels from single cone to single ganglion cell to single bipolar cell
The message that goes to the brain delivered from ganglion cells carry both _____ and ____ information of the finest resolution
Spatial, spectral
What would happen if there were no retinal layers and information went from photoreceptors directly to the brain?
Coarse-grained, blurry image