Question 1

Lateral inhibition has previously been used to explain _____.

Accepted Answer

Lateral inhibition has been used to explain the Hermann Grid, Mach bands, and the Chevreul illusion.

Question 2

The flow of information in the LGN is best described as _____.

Accepted Answer

The flow of information in the LGN is bidirectional, with signals coming from both the retina and the cortex to the LGN. The retina sends visual information to the LGN, which then relays the information to the visual cortex. Meanwhile, the cortex also sends feedback signals to the LGN, modulating how the LGN processes visual information.

Question 3

You can create a version of the _____ by illuminating a light-colored surface with a desk lamp and casting a shadow with a piece of paper.

Accepted Answer

B

Question 4

When _____, lateral inhibition can no longer account for the Hermann Grid.

Accepted Answer

When the lines in the Hermann Grid are made curvy, lateral inhibition, a mechanism in the visual system that creates the illusion of darker areas at the intersections, can no longer explain the phenomenon because the geometric structure necessary for this effect is disrupted.

Question 5

_________: Limulus :: ________: human retina.

Accepted Answer

Limulus (horseshoe crab) has lateral plexuses, which are composed of both horizontal and amacrine cells, whereas the human retina also has a lateral plexus composed of horizontal and amacrine cells.

Question 6

The Nobel Prize winners who conducted the pioneering research on the physiology of striate cortex neurons were _____.

Accepted Answer

The Nobel Prize winners who conducted the pioneering research on the physiology of striate cortex neurons were David Hubel and Torsten Wiesel.

Question 7

In Hermann's grid, a possible explanation for why gray areas appear at the intersections is because _____.

Accepted Answer

In Hermann's grid, the gray areas appear at the intersections due to lateral inhibition, which means that the activity of neurons in one area inhibits the activity of neighboring neurons. At the intersections, the amount of inhibition is twice as great as the inhibition between each square, leading to the perception of gray areas.

Question 8

The inability of lateral inhibition to explain some perceptual effects suggests that some contrast effects are based in _____.

Accepted Answer

Lateral inhibition occurs within the retina and can explain certain perceptual effects such as Mach bands, but other contrast effects such as simultaneous contrast and color contrast are believed to be based in the cortex.

Question 9

Hartline et al. (1956) selected the Limulus to demonstrate lateral inhibition because _____.

Accepted Answer

Hartline et al. selected the Limulus to demonstrate lateral inhibition because it was possible to illuminate a single receptor without illuminating its adjacent receptor, which is necessary for demonstrating the concept of lateral inhibition.

Question 10

The inability of lateral inhibition to account for more complex effects shows how _____.

Accepted Answer

The fact that lateral inhibition alone cannot account for more complex effects indicates that physiological explanations may need to be modified by perceptual results.

Question 11

In Mach bands, the darker area sends _____ lateral inhibition to the lighter area than the lighter area sends to the darker area.

Accepted Answer

Mach bands are an illusion that occurs due to lateral inhibition among adjacent neurons in the visual system. In this case, the darker area sends less lateral inhibition to the lighter area than the lighter area sends to the darker area, which amplifies the contrast between the two areas and creates the illusion of a band of increased intensity at the edge. So, the answer is A, i.e., less.

Question 12

Human lateral inhibition is most likely accomplished by _____.

Accepted Answer

Bipolar cells in the retina are responsible for lateral inhibition, a process that enhances the contrast between adjacent receptive fields. When a photoreceptor is stimulated, it inhibits the activity of neighboring photoreceptors via lateral inhibition by activating the bipolar cell. This enhances the edge detection ability of the visual system. End-stopped cells, extrastriate cells, and dissociative cells are not involved in lateral inhibition.

Question 13

Chad is reading when he sees an insect land on the corner of his book. He then makes an eye movement to look at the insect. The structure of the visual system that is most likely responsible for making this eye movement is the _____.

Accepted Answer

The superior colliculus is responsible for directing eye movements towards objects of interest in the visual field, such as the insect that landed on Chad's book.

Question 14

Most of the signals travel from the retina to the _____ via the optic nerve.

Accepted Answer

The lateral geniculate nucleus is the primary center for processing visual information received from the retina. Signals from the retina travel via the optic nerve to reach the lateral geniculate nucleus. The temporal cortex is involved in processing auditory information and language, the superior colliculus is involved in visual attention and eye movements, and the visual homunculus is a representation of the body in the visual cortex, but not a destination for signals travelling directly from the retina.

Question 15

Neurons in the LGN have _____ receptive fields.

Accepted Answer

Neurons in the lateral geniculate nucleus (LGN) have center-surround receptive fields. This means that each neuron has a central region where it is sensitive to light, surrounded by an inhibitory region where it is less sensitive. This organization allows for the detection of contrast and edges in visual stimuli.

Question 16

The flow of information to the _____ from the _____ is greater than from the _____.

Accepted Answer

The answer of  The flow of information to the _____...

Question 17

A receptor array in the Limulus is connected by the lateral plexus. Receptor "A" is located 5 receptors to the left of Receptor "B." What stimulation will result in the greatest firing rate recorded from "A"

Accepted Answer

Stimulating receptor "A" with 10 units of illumination without stimulating "B" will result in the greatest firing rate from "A" because stimulating "B" would cause lateral inhibition, reducing "A"'s firing rate.

Question 18

A neuron with an excitatory center-inhibitory surround receptive field will respond most when we stimulate _____.

Accepted Answer

A neuron with an excitatory center-inhibitory surround receptive field will respond most when only the center is stimulated. Stimulation of the surround will lead to inhibition of the neuron's activity, resulting in decreased responsiveness.

Question 19

The gray intersections in the Hermann Grid _____.

Accepted Answer

The gray intersections in the Hermann Grid support the claim that "perception is not the same as the physical stimulus." This phenomenon occurs due to the way our visual system processes information, creating an illusion of gray areas where there are none. It is not a physical property present in the stimulus, but rather a result of how our brain processes it.

Question 20

The area on the retina that influences the firing rate of the neuron is called the _____.

Accepted Answer

The receptive field is the area on the retina that influences the firing rate of the neuron. This refers to the specific location on the retina from which the neuron receives input and responds to visual stimuli.

Quiz 3: Neural Processing