Deck 2: Signaling in the Visual System

Question 1

We read words on a page with our central visual field. This is because the

A) visual field is distorted in the peripheral visual field.
B) peripheral visual field only responds to motion.
C) central visual field has fewer photoreceptors.
D) central visual field has a higher density of photoreceptors.
E) retinal image is only focused at the central visual field.

Answer 1

D

Question 2

The lateral geniculate nucleus is comprised of six layers. Each layer receives visual information from

A) the entire visual field of one eye.
B) the entire visual field of both eyes.
C) half of the visual field of one eye.
D) half of the visual field of both eyes.
E) half of the inputs from each eye.

Answer 2

C

Question 3

A neuron in the lateral geniculate nucleus (LGN) receives input from many retinal ganglion cells. This property is called

A) receptive field.
B) convergence.
C) divergence.
D) accommodation.
E) dilation.

Answer 3

B

Question 4

A neuron in the lateral geniculate nucleus (LGN) sends input to many visual cortical cells. This property is called

A) receptive field.
B) convergence.
C) divergence.
D) accommodation.
E) dilation.

Question 5

What is one result of converging input in the visual system?

A) Assembly of complex receptive fields from simpler ones
B) Conductance of action potentials to the Lateral Geniculate Nucleus
C) Sharing information from one part of the visual field to many cells
D) A reduction in receptive field size from photoreceptors to LGN cells
E) Monocular receptive fields

Question 6

Action potentials in the retinal ganglion cells report the presence of

A) light in a particular portion of the receptive field.
B) dark in a particular portion of the receptive field.
C) a contrasting pattern of light and dark in a particular portion of the receptive field.
D) uniform illumination across the receptive field.
E) none of the above-retinal ganglion cells do not respond to light.

Question 7

Severing the optic chiasm along the midline will result in blindness in

A) the left visual field.
B) the right visual field.
C) the central visual field.
D) the peripheral visual field.
E) all visual fields.

Question 8

The left visual cortex receives information from the

A) left LGN only.
B) right LGN only.
C) left eye only.
D) right eye only.
E) left visual field only.

Question 9

The first general step in the analysis of the visual world is to

A) define edges and lines.
B) categorize objects.
C) determine absolute light levels.
D) detect motion.
E) recognize faces.

Question 10

Which of the following is true about excitatory and inhibitory portions of the receptive field for a simple cell in visual cortex?

A) They are always overlapping.
B) They can be binocular.
C) They are always concentric.
D) They are interchangeable.
E) They are always on-center.

Question 11

Which of the following is true about retinal ganglion cell receptive fields?

A) Neighboring retinal ganglion cells always display the same receptive fields.
B) Neighboring retinal ganglion cells always display different receptive fields.
C) Neighboring retinal ganglion cell receptive fields do not overlap.
D) Neighboring retinal ganglion cell receptive fields overlap substantially.
E) Neighboring retinal ganglion cell receptive fields are antagonistic.

Question 12

What is meant by an "excitatory" portion of the receptive field?

A) The portion of the receptive field that increases the number of action potentials fired by a cell
B) The portion of the receptive field that decreases the number of action potentials fired by a cell
C) The portion of the receptive field that causes the action potentials fired by a cell to increase in size
D) The portion of the receptive field that causes the action potentials fired by a cell to decrease in size
E) The portion of the receptive field that causes other neurons to fire action potentials

Question 13

What kind of Retinal Ganglion Cell slow down or stop signaling when the central area of their field is illuminated?

A) On-center retinal ganglion cells
B) Off-center retinal ganglion cells
C) Reverse threshold retinal ganglion cells
D) M cells
E) P cells

Question 14

Light shone onto the surround of an off-center receptive field causes _______ of the cell

A) excitation
B) inhibition
C) integration
D) temporal Summation
E) accommodation

Question 15

Shining an annulus ("donut") of light on the surround portion of an on-center ganglion cell's receptive field will cause that ganglion cell to fire

A) more action potentials compared to baseline.
B) fewer action potentials compared to baseline.
C) the same frequency of action potentials compared to baseline.
D) more action potentials if the light is very bright.
E) None of the above: Light in the surround does not change the firing rate of retinal ganglion cells.

Question 16

Retinal ganglion cell responses can best be described by which of the following?

A) Retinal ganglion cells respond to the presence of light.
B) Retinal ganglion cells respond to dark spots in the light.
C) Retinal ganglion cells respond to light spots in the dark.
D) Retinal ganglion cells respond to light spots or dark spots depending on their receptive field.
E) Retinal ganglion cells respond to changes in light levels.

Question 17

You are recording action potentials from a monkey retinal ganglion cell, and discover that the cell has a small receptive field, high spatial resolution, and is sensitive to color. What kind of cell are you recording from?

A) Magnocellular
B) Parvocellular
C) X cell
D) Y cell
E) W cell

Question 18

You are recording action potentials from a cat Retinal Ganglion Cell, and discover that the cell has a large receptive field, low spatial resolution, and conducts action potentials quickly. What kind of cell are you recording from?

A) Magnocellular
B) Parvocellular
C) X cell
D) Y cell
E) W cell

Question 19

The relationship between the center and surround portions of the Retinal Ganglion Cell receptive field can best be described as

A) synchronous.
B) subtractive.
C) antagonistic.
D) synergistic.
E) mutually compatible.

Question 20

Light completely covering the receptive field of an off-center retinal ganglion cell will produce

A) a substantial increase in action potential firing.
B) a substantial decrease in action potential firing.
C) no substantial change in action potential firing.
D) a substantial decrease in action potential firing when the light is removed.
E) responses in LGN cells but no response in retinal ganglion cells.

Question 21

Two gray squares that have the same luminance value may appear to be different in a scene. This effect is due to the fact that

A) photoreceptors do not carry information about luminance.
B) photoreceptors only carry information about contrast.
C) retinal Ganglion Cells and geniculate cells respond to local contrast, not luminance.
D) retinal Ganglion Cells and Geniculate cells respond to luminance, not contrast.
E) visual cortical cells do not respond to light.

Question 22

Which of the following cells would respond best to the image of a fly against a cloudless sky?

A) Photoreceptor
B) Retinal ganglion cell
C) Cortical simple cell
D) Cortical complex cell
E) All would respond equally well.

Question 23

Which of the following is a difference between simple and complex cells in the visual cortex?

A) Simple cells have end inhibition while complex cells do not.
B) Simple cells have orientation selectivity while complex cells do not.
C) Simple cells have distinct "off" regions while complex cells do not.
D) Simple cells have binocular visual fields while complex cells do not.
E) Simple cells have movement sensitivity while complex cells do not.

Question 24

Which of the following statements is supported by the progression of neural representation of visual information through the visual system?

A) Neural representations become more abstract from lower-order units to higher-order units.
B) Lower-order neurons convey luminance information, higher-order units convey location information.
C) The progressive integration of information in the visual system leads to highly specific stimulus requirements for higher-order neurons.
D) Information from each eye is separated and processed in only one hemisphere of the brain.
E) Neuronal firing does not seem to play a part in perception of objects.

Question 25

When an end-inhibited cell in visual cortex fires action potentials, what information is most likely being conveyed?

A) There is diffuse light in the area of the receptive field.
B) There is a bar of light in the receptive field.
C) There is a vertical bar of light in the receptive field.
D) There is a vertical bar of light moving from left to right in the receptive field.
E) There is a corner within the receptive field.

Question 26

When a simple cell in visual cortex fires action potentials, what information is most likely being conveyed?

A) There is diffuse light in the area of the receptive field.
B) There is a bar of light in the receptive field.
C) There is a vertical bar of light in the receptive field.
D) There is a vertical bar of light moving from left to right in the receptive field.
E) There is a corner within the receptive field.

Question 27

In which of the following layers of visual cortex are simple cells typically found?

A) Layer 1
B) Deep layer 2
C) Superficial layer 3
D) Layer 4
E) Layer 5

Question 28

Which of the following cell types has the most stringent stimulus requirements for activating its receptive field?

A) Photoreceptor
B) Retinal ganglion cell
C) Lateral geninculate nucleus cell
D) Cortical simple cell
E) Cortical complex cell

Question 29

Experiments using calcium imaging to examine responses of cells in mouse visual cortex to moving gratings reveals that

A) cortical cells do not respond to drifting grating stimuli.
B) neighboring cortical cells show similar responses.
C) cellular responses are selective for the direction of the stimulus.
D) orthogonal stimuli activate overlapping populations of neurons.
E) mouse visual cortex is arranged identically to primate visual cortex.

Question 30

Corners, edges, and angles are best detected by which of the following cells?

A) Photoreceptors
B) Retinal ganglion cells
C) Lateral geniculate nucleus cells
D) Cortical simple cells
E) Cortical complex cells

Question 31

A square that appears light when surrounded by a black border can be made to appear dark merely by increasing the brightness of the surround. This suggests that the visual cortex

A) receives action potentials that convey information about luminance from the entire visual field.
B) receives action potentials only from cells at the edges of the square.
C) identifies the absolute levels of brightness in an image.
D) responds to the periphery more than to the center of the visual field.
E) receives information about color through the periphery of the visual field.

Question 32

A property of certain cells in visual cortex is that they respond only to a bar of light of a certain length. This property is called

A) length constancy.
B) edge detection.
C) off-surround.
D) response selectivity.
E) end inhibition.

Question 33

You record from a cell a robust response to a bar of light 10cm in length. When you change the stimulus to a bar of light 15 cm in length, you no longer see a response. What characteristic of this cell's receptive field does your finding suggest?

A) Pattern completion
B) Size specificity
C) End inhibition
D) Orientation selectivity
E) Direction selectivity

Question 34

In any given visual scene, the best-responding Retinal Ganglion Cells will be those with _______ in their receptive field.

A) diffuse illumination
B) maximum contrast
C) moving spots of light
D) moving bars of light
E) horizontal lines

Question 35

Many cells respond best to bars of light moving in one direction. This property of direction selectivity is found commonly in

A) photoreceptors.
B) retinal ganglion cells.
C) LGN cells.
D) simple cells.
E) complex cells.

Question 36

Simple cells in primary visual cortex respond most strongly to which of the following?

A) A bar of light in any orientation
B) A spot of light
C) A bar of light in a particular orientation
D) An annulus ("donut") of light
E) A complex visual scene

Question 37

The receptive fields of cells carrying information from the central visual field tend to be _______ compared to the receptive fields of cells carrying information from peripheral visual field.

A) more active
B) less active
C) larger
D) smaller
E) about the same size

Question 38

You record from a cell in the cat visual cortex, and find a cell that responds only when a bar of light with a particular width is presented at a particular angle. What kind of cell is this?

A) Simple cell
B) Complex cell
C) Hypercomplex cell
D) On-center cell
E) Off-center cell

Question 39

Photoreceptors signal _______ while retinal ganglion cells and lateral geniculate nucleus cells signal _______.

A) light intensity; contrast
B) orientation; contrast
C) contrast; light intensity
D) contrast; orientation
E) light intensity; orientation

Question 40

Binocular receptive fields found in cortical simple cells can be used in the perception of

A) movement.
B) depth.
C) color.
D) size.
E) light.

Question 41

In the visual cortex, a complex cell's receptive field requires that a stimulus fall

A) only on the center of the receptive field in any orientation.
B) only on the surround of the receptive field in any orientation.
C) anywhere in the receptive field in a specific orientation.
D) anywhere in the receptive field in any orientation.
E) on both eyes simultaneously.

Question 42

Which of the following has a receptive field that can be best described as monocular and having distinct on and off regions?

A) Photoreceptor
B) Retinal ganglion cell
C) Lateral geniculate nucleus cell
D) Visual cortex simple cell
E) Visual cortex complex cell

Question 43

Dr. Bakai sees a patient in her clinic who complains of a severe headache. When asked to describe her friend's face, she claims that all she can see is a pattern of wallpaper where her friend's head should be. Which of the following might Dr. Bakai consider in making her diagnosis?

A) A problem with the patient's photoreceptors
B) A problem with the patient's retinal ganglion cells
C) A problem with the patient's lateral geniculate nucleus
D) A problem with the patient's simple cells in visual cortex
E) A problem with the patient's complex cells in visual cortex

Question 44

The orientation of a bar of light is important for responses for which of the following cell types?

A) Photoreceptor
B) Retinal ganglion cell
C) Lateral geniculate nucleus cell
D) Cortical simple cell
E) None of the above

Question 45

Compare the anatomical arrangement of the photoreceptors in the fovea with that in the peripheral visual field. What is the functional significance of this arrangement?

Question 46

Describe the receptive field of an on-center retinal ganglion cell and a description of the cell's response to illumination.

Question 47

What happens when a spot of light in the center of an off-center retinal ganglion cell's receptive field is removed?

Question 48

How does the information carried by retinal ganglion cells and cells in the lateral geniculate nucleus differ from the information carried by photoreceptors? Support your answer using information about receptive fields in each cell type.

Question 49

Describe the progression of image information from the photoreceptors to the primary visual cortex. What information is being conveyed at each stage?

Question 50

How do retinal ganglion cells and lateral geniculate nucleus cells respond to diffuse light? Why?

Question 51

In addition to trains of action potentials from single retinal ganglion cells, what other information might the brain use to analyze visual information?

Question 52

Explain the difference between responses of simple and complex cells in primary visual cortex.

Question 53

Describe the completion phenomenon, and discuss what is thought to be the neural basis for it?

Question 54

Discuss the function of a receptive field with end inhibition, and explain how it differs from a conventional "off" region of a receptive field

Question 55

Intracellular recordings from complex cells in the visual cortex reveals that these cells receive most of their synaptic contacts through long-latency inputs. What is the significance of this finding?

Question 56

Describe how the visual system uses information about local differences in illumination to convey information about the visual world. Use examples as appropriate.

Question 57

What role does integration play in the receptive field of a retinal ganglion cell?

Question 58

Explain how the receptive field properties of simple cells in primary visual cortex arise from the responses of retinal ganglion cells.

Question 59

Explain how the receptive field properties of complex cells in primary visual cortex arise? Include a description of the cells and receptive fields that provide input to complex cells.