Deck 2: The Beginnings of Perception

Question 1

Our perception of the environment depends on

A) the properties of the objects in the environment.
B) the properties of the electrical signals in the nervous system.
C) both the properties of the environmental objects and properties of the electrical signals in the nervous system.
D) none of these are true.

Answer 1

C

Question 2

In the early stages of _______, peripheral rod receptors are destroyed leading to poorer peripheral vision.

A) macular degeneration
B) retinitis pigmentosa
C) presbyopia
D) retinal hypopolarization

Answer 2

B

Question 3

A wavelength of 100 nm would fall in the ______ range of the electromagnetic spectrum.

A) X-rays
B) ultraviolet rays
C) infrared rays
D) gamma rays

Answer 3

B

Question 4

Which of the following is true about the difference between the rods and the cones?

A) The rods control vision in high illumination conditions, and the cones control vision in low illumination conditions.
B) The rods are packed in an area called the fovea, and the cones are found more in the peripheral retina.
C) There are about 120 million rods in the human eye and about 5 million cones.
D) The only difference between the rods and the cones is physical shape.

Question 5

Individual suffering from myopia may have difficulty seeing _______ objects clearly. Often times they are also referred to as being _______.

A) nearby; farsighted
B) nearby; nearsighted
C) distant; farsighted
D) distant; nearsighted

Question 6

_______ reacts to light to start the process of transduction.

A) Opsin
B) Retinal
C) Choroid
D) Thyric acid

Question 7

The structure of the eye that provides about 80% of the eye's focusing power is the

A) iris.
B) pupil.
C) cornea.
D) lens.

Question 8

The distance at which the lens can no longer bring a close object into focus is called the

A) far point.
B) near point.
C) high point.
D) coupee point.

Question 9

Nina does a demonstration of "seeing" the blind spot, in which a grid pattern surrounds the black dot that disappears when it falls on the blind spot. What does Nina most likely see in the area where the dot disappears?

A) a blurry gray area
B) a white circle
C) nothing
D) a continuation of the grid pattern

Question 10

LASIK surgery is used to treat _______ by cutting a small flap in the _________.

A) myopia; cornea
B) myopia; lens
C) hyperopia; cornea
D) presbyopia; lens

Question 11

The isomerization of a single pigment molecule triggers what is best described as a

A) chain reaction.
B) ballistic expansion.
C) hyperactive potential.
D) hypopolarization wave.

Question 12

Visible light is between _____ and ____ nm within the electromagnetic spectrum.

A) 100; 400
B) 400; 700
C) 500; 1000
D) 900; 1500

Question 13

The episode of "Mythbusters" cited in the textbook demonstrated that dark adaptation was the reason why

A) poker players wear sunglasses.
B) pirates wore eyepatches.
C) cardinals have good night vision.
D) giants have poor night vision.

Question 14

Lorelei's mother is 60 years old. Because of the condition called ______, the closest distance at which she can focus an object is probably about ____ cm.

A) cataracts; 20
B) cataracts; 40
C) presbyopia; 100
D) dermabrasion; 150

Question 15

A retinal condition that destroys the cones in the fovea is

A) macular degeneration.
B) retinitis pigmentosa.
C) presbyopia.
D) retinal hypopolarization.

Question 16

Jan tries to focus on the tip of her pencil as she brings it closer to her. She feels the strain on her eye as she does this. What she is feeling in her eye is due to the process called

A) inhibition.
B) reflection.
C) accommodation.
D) assimilation.

Question 17

Vera has hyperopia, and tends to get headaches when she reads. This is because

A) Vera also has presbyopia and has the constant need to accommodate.
B) Vera also has myopia and is unable to accommodate.
C) Vera has just had LASIK surgery and her ciliary muscles are damaged.
D) Vera is 5-years-old and lacks the visual acuity to read.

Question 18

Light can be described in terms of wavelength, or as consisting of small packets of energy called

A) photons.
B) electrons.
C) ions.
D) pulsars.

Question 19

The visual pigment molecules are contained in the

A) inner segments of the visual receptors.
B) outer segments of the visual receptors.
C) axons of the rods.
D) axons of the cones.

Question 20

The blind spot is located

A) in the fovea.
B) in the vitreous.
C) where the optic nerve leaves the eye.
D) at the optic chiasm.

Question 21

There are ____different cone receptors, each with different absorption spectra.

A) 2
B) 3
C) 4
D) 7

Question 22

The flow of ions that create the action potential are caused by the changes in the ______ of the nerve fiber.

A) suppression
B) permeability
C) accommodation
D) assimilation

Question 23

As stimulus intensity is increased, recording from a single neuron shows

A) the amplitude of the action potential increases.
B) the amplitude of the action potential decreases.
C) the amplitude of the action potential may increase or decrease, depending on the stimulus.
D) the rate of firing of the nerve fiber increases.

Question 24

Rushton demonstrated that the physiological mechanism behind dark adaptation is

A) visual pigment regeneration.
B) the enzyme cascade.
C) modular organization.
D) photon remission.

Question 25

Which of the following statements best defines the "propagated response"?

A) Once a response is triggered, the response travels the length of the axon without decreasing in amplitude.
B) Once a response is triggered, the response gradually increases in amplitude as it travels down the length of the axon.
C) The response increases the positive charge of the chlorine ions throughout the length of the axon.
D) The number of negative potassium ions increase the closer the impulse is to the dendrites.

Question 26

To isolate the rod portion of the dark adaptation curve, researchers

A) use rod monochromats as the participants.
B) present the stimulus foveally.
C) present the stimulus in the periphery.
D) use cone monochromats as participants.

Question 27

The "rod-cone break" in the dark adaptation curve occurs after about ___ in the dark.

A) 30 seconds
B) 2 minutes
C) 7 minutes
D) 30 minutes

Question 28

The three major parts of a neuron are

A) dendrites, cell body, and axon.
B) axon, nerve fiber, and receptor.
C) receptor, transmitter, and median.
D) receptor, dendrites, and conductor.

Question 29

Synaptic vesicles contain chemicals called _________ that are released across the synapse to the next neuron.

A) electrolytyes
B) collagens
C) neurotransmitters
D) glial cells

Question 30

The Purkinje shift

A) is when reds appear brighter than blues in well-lit conditions, but blues appear brighter than reds in dim conditions.
B) is when blues appear brighter than reds in well-lit conditions, but blues appear brighter than reds in dim conditions.
C) is when details that are easily seen in well-lit conditions become more difficult to see in low-light conditions.
D) demonstrates the importance of eye movements in visual pigment regeneration.

Question 31

__________ is necessary for the neural transmission and processing of information.

A) Inhibition
B) Excitation
C) Exhibition
D) Both inhibition and excitation

Question 32

The difference in charge between the inside and the outside of the nerve fiber when the nerve is at rest is _____ mV.

A) -70
B) -10
C) 0
D) +19

Question 33

The upper limit of a neuron's firing rate is estimated to be ____ impulses per second.

A) 20
B) 100
C) 800
D) 4400

Question 34

The peak in the spectral sensitivity curve is about _____ for the rods, and about _____ for the cones.

A) 700 nm; 400 nm
B) 450 nm; 800 nm
C) 500 nm; 560 nm
D) 600 nm; 450 nm

Question 35

At the beginning of the action potential, _____ ions flow from outside the nerve fiber into the nerve fiber.

A) positive potassium
B) negative potassium
C) positive sodium
D) negative sodium

Question 36

The _____ analogy is used to describe the relationship of neurotransmitters with receptor sites.

A) "needle in a haystack"
B) "lock and key"
C) "stadium wave"
D) "rolling stone"

Question 37

____________ is the process by which inhibitory transmitters cause the inside of the neuron to become more negative.

A) Hyperpolarization
B) Depolarization
C) Antipolarization
D) Repolarization

Question 38

Cone spectral sensitivity is measured by having the observer

A) look up and blink.
B) look straight forward without blinking.
C) look directly into a light.
D) look to the side of a flashing light.

Question 39

When visual pigments become bleached they are

A) dead.
B) fully regenerated.
C) color sensitive.
D) detached from the opsim.

Question 40

The rate of firing of the postsynaptic neuron depends on the amount of ______ input it receives from the presynaptic neuron.

A) excitation
B) inhibition
C) equalizing
D) both excitation and inhibition

Question 41

The difficulty of reading under dim light conditions can be explained by

A) the increased sensitivity of cones under low light conditions.
B) the increased acuity of cones under low light conditions.
C) the fact that rod functioning predominates during dark adaptation, therefore poor acuity.
D) the fact that cone functioning predominates during dark adaptation, therefore poor acuity.

Question 42

Convergence results in _________ sensitivity and _______ acuity.

A) increased; increased
B) increased; decreased
C) decreased; decreased
D) decreased; increased

Question 43

(a) What is the "blind spot"?
(b) Discuss two reasons why we are not usually aware of the blind spot.

Question 44

Describe the process of synaptic transmission. Include in this description the differences between excitatory and inhibitory transmitters.

Question 45

Converging circuits with excitation and inhibition are associated most closely with which step of the perceptual process?

A) recognition
B) attention
C) neural processing
D) the environmental stimulus

Question 46

(a) In words and/or diagrams, discuss why convergence of the rods results in increased sensitivity, but decreased acuity.
(b) In words and/or diagrams, discuss why the lack of convergence in the foveal cones results in decreased sensitivity, but increased acuity.

Question 47

Acuity is better in the ____ than in the _____.

A) periphery; fovea
B) optic disk; fovea
C) optic disk; cornea
D) fovea; periphery

Question 48

(a) Draw a graph (with appropriate axis labels) of the dark adaptation curve.
(b) Describe the methodology used to isolate the rod component of the curve, and the cone component.
(c) Discuss how Rushton demonstrated the physiological basis to dark adaptation.

Question 49

Describe how preferential looking and visual evoked potentials technique have been used to study infant perception.

Question 50

The stimuli used in the preferential looking technique of testing infant acuity are

A) geons.
B) gratings.
C) Greebles.
D) faces.

Question 51

Rods and cones synapse with ______ cells, which then synapse with ____ cells.

A) ganglion; bipolar
B) bipolar; ganglion
C) amacrine; unipolar
D) amacrine; bipolar

Question 52

Name, define, and discuss the treatment for three kinds of focusing problems.

Question 53

Which of the following is a reason for the poor acuity of newborns?

A) The rods are not developed at birth.
B) Newborns have too much visual pigment in the cones.
C) A newborn's rods have very narrow inner segments.
D) The visual cortex of the newborn is only partially developed.

Question 54

Using words and/or diagrams, circuits with (a) no convergence; (b) convergence; and (c) convergence with inhibition affect neural firing rate.

Question 55

(a) What are the basic properties of action potentials?
(b) How do these properties relate to perception?

Question 56

Reading the eye chart in an optometrist's office is used to measure

A) acuity.
B) sensitivity.
C) receptive fields.
D) creativity.

Question 57

Acuity develops to almost 20/20 vision by the time the infant is

A) one month old.
B) two months old.
C) one year old.
D) two years old.

Question 58

If we compare how the rods and cones converge onto other retinal neurons, we find that

A) foveal cones converge more than the peripheral rods.
B) rods and cones converge equally.
C) rods converge more than foveal cones.
D) horizontal cells converge onto the peripheral cones.

Question 59

(a) Discuss the major differences between the rods and the cones.
(b) Describe two retinal disorders that differentially affect the rods and the cones.