Perception

Question 1

What is the difference between sensation and perception?

Answer 1

Sensation is what happens when our sensory modalities (vision, hearing, taste, etc.) are activated.
Perception is how we understand these senses.

Question 2

What are the three stages of sensation?

Answer 2

1. reception
2. transduction
3. transmission through neural pathways to the brain

Question 3

Stimuli from the outside world are converted into neural impulses to be processed by our brains through what process?

Answer 3

transduction

Question 4

What two processes stop you from feeling your shirt press against the hairs on your arms all day?

Answer 4

1. sensory adaptation: when the hairs on our arms are constantly being pressed, we simply stop responding to the feeling of pressure
2. sensory habituation: the pressure on our hairs stops being novel, so there is no reason for us to continue paying attention to it

Question 5

If you are zoning out in class and your teacher suddenly uses a swear word, you will snap back to attention. What is the phenomenon called that is responsible for this?

Answer 5

The cocktail party phenomenon/effect
involuntarily focuses our attention on something salient, like hearing our name in a roomful of people, or hearing a teacher curse.

Question 6

What are the “energy senses” and why are they called that?

Answer 6

• vision
• audition (hearing)
• touch
These senses convert stimuli into energy, like light, sound waves, and pressure.

Question 7

What are the “chemical senses” and why are they called that?

Answer 7

• taste (gustation)
• smell (olfaction)
These senses take stimuli and convert them into chemical signals to be processed.

Question 8

What is a human’s dominant sense?

Answer 8

vision

Question 9

What are the factors in seeing a bright light or a blue sky versus a black jacket?

Answer 9

Light intensity will affect how bright an object appears

color or hue is affected by the light wavelength in the visual color spectrum an object reflects.

Question 10

Describe cornea:

Answer 10

protective covering of the eye, where light first enters and is focused.

Question 11

Describe pupil:

Answer 11

The black part in the middle of the eye, the pupil acts like the shutter of a camera, and is controlled by the iris.

Question 12

Describe iris:

Answer 12

The iris is the colored disc surrounding the pupil that changes its dilation, allowing more or less light in.

Question 13

Describe the lens

Answer 13

The lens focuses light entering through the pupil (called accomodation), then flips and inverts the image and projects it onto the retina.

Question 14

Describe retina:

Answer 14

The upside-down and inverted image is projected onto the retina, where neurons are activated to interpret the image via transduction. The retina has several layers of cells involved in transduction.

Question 15

What are the parts of the retina?

Answer 15

• rods and cones
• fovea
• ganglion cells
• blind spot

Question 16

When the sun sets and everything in the dark around you looks bluish, are your rods or your cones activated?

Answer 16

Rods are activated.
Rods react to light, rather than color, with the exception of blue, which explains why we can only see shades of blue in the dark. Cones are activated by other colors.

Question 17

Describe fovea:

Answer 17

The fovea is an indentation in the retina. It is the eye’s fixation point, or the part of the eye used when attending to detail.

Question 18

Why do we have a “blind spot”?

Answer 18

The area where the optic nerve leaves the retina has no photoreceptors (rods or cones).

Question 19

The optic nerve is comprised of axons from what?

Answer 19

ganglion cells

Question 20

What is the lateral geniculate nucleus (LGN)

Answer 20

visual part of the thalamus that receives information from the optic nerve.