Sensation and Perception Unit 2

Question 1

Sensation

Answer 1

Process by which information in the psychical world is detected by sensory organs

Eyes, ears, nose/mouth, skin (somesthetic senses, temp and pain, vestibular: balance, kinesthetic: location of body in space, muscles/joints)

Question 2

Perception

Answer 2

Process by which sensory information is interpreted in the brain
Seeing and hearing, the way it is understood happens in the brain

Question 3

What process does sensation begin with ?

Answer 3

Transduction- all sensory organs are responsible for transduction

Question 4

What do transducers do

Answer 4

Almost translation machines, they translate energy
Taking in vast amounts of information in the environment, it exists as various forms of energy, (ex. When you taste things/ smell things, its chemical energy)

Brain doesn’t understand any of this, the transducers translates all these various types of energy into electrical energy (action potential)
When you taste things/ smell things, its chemical energy

Question 5

Challenge and solution during sensation

Answer 5

Challenge- Sensory organs can transduce the avalanche of sensations available in the environment, but the brian cannot process all of this information

Solution- Restrict information through selection and selective attention

Question 6

Challenge with attention

Answer 6

Extremely limited

Question 7

What do we pay attention to

Answer 7

Physically salient - bright, loud, sharp, taste bad
Appealing or interesting (attractive, curious)
Personal meaning or importance (ex. cocktail party effect)- Your name, your attention switches
Things that allow you to achieve your goals

Question 8

Yarbus 1967

Answer 8

found eye tracking shows that people look toward aspects of the painting that will provide the information needed to meet their goals (the instruction)
Goals impact attention and therefore what we perceive
When we focus our attention on one specific place, we will miss some stimuli
Sensory information is not always sent to the brain for processing even when you think you’ve seen everything

Question 9

Yarbus vs the gorilla

Answer 9

Gorilla is in the middle of it all, straight through field of vision 50% of people did not see it, the information passed through visual receptors but was not comprehend
Demonstrates how attention can narrow to include only things that are relevant to our goals

Question 10

Simons and Chabris 1999

Answer 10

white team passing basketball, did you see the gorilla?

Question 11

Inattentional blindness

Answer 11

ail to see elements of a scene you are watching (objects, actions)
Happens for two reasons
Focused on a goal
What you saw was Unexpected

Question 12

Change blindness

Answer 12

Fail to see gradual change to elements of a scene you are watching

Question 13

Chabris, Weinberger, Fontarine and Simmons (1999)

Answer 13

Count the number of times the runner in front of you touches their hat, while a staged fight went down
Interested in how many people would report haven seen this altercation

Ran it at night time- How many saw the fight: 33%

Daylight- How many people saw the fight: 60%

Take home message: It is possible to “see” (ie. sense) something without “seeing” (ie. perceiving)

Unanswered question- Do expert searchers’ experience inattentional blindness?

Question 14

Drew, Vo, and Wolfe (2013)

Answer 14

Had radiologist who were trained to find cancer on scans, to see if they could find a hidden gorilla in the scan (was 50x larger than cancer in brain)
83% of the radiologists did NOT see the gorilla
With eye goggles, 80% of the 83% of people looked straight at it

Take home-
Even experts experience inattentional blindness
Confirmed in 2022 meta-analysis

Question 15

How is information from the senses combined during perception?

Answer 15

Brain doesn’t deal with information coming from one sense at a time; it combines information from all senses; (In previous studies^ only one was used (visual))
This is multimodal integration

Question 16

Multimodal integration

Answer 16

Playing sports: an amazing baseball catch
Visual system, tracking the ball, surroundings, kinesthetic, vestibular

Playing music: Reading music while playing

Speech: couldn’t understand people during covid bc couldn’t see mouth

Question 17

Why do we see similarities in perception across people?

Answer 17

Similarities due to transduction -Human transducers work in the same way for most people, yielding a similar perceptual experience.

Similarities due to experience - We often use similar perceptual rules to interpret stimuli and consequently have similar perceptual experiences

Shape constancy

Brightness constancy

Question 18

Why do we see differences in perception across people?

Answer 18

Differences due to transduction:
Diversity due to transduction
Diversity due to experience
Cultural diversity in color perception

Question 19

Winawer ET AL 2007

Answer 19

Cultural diversity in color perception
Background: Unlike English, Russian distinguishes between lighter blues (“goluboy”) and darker blues (“siniy”)

Method:
A blur ‘test square’ appears on the screen, followed by two options
Select the option that matches the test square

Results:
Russian speakers faster to discriminate two colors when they fell into different linguistic categories (one light, one dark) than when they are in the same linguistic category
English speakers did not show any difference in discriminating different shades of blue

Take home message:
Language, which is a product of culture, affects perception of color

Revisiting research:
Winerwar compared English and Russian speakers on how quickly the were able to match blue squares to a standard

Question 20

Bottom up processing

Answer 20

No experience or context related to the stimuli; must focus on its individual ‘parts’ and try to construct something that is meaningful from them
Relies heavily on the S2 (the rider)

Question 21

Top down processing

Answer 21

Past experience and/or context allow for very quick perception of the stimulus
Relies heavily on the S1 (the elephant)

Question 22

absolute threshold

Answer 22

The minimum amount of physical energy that can be detected 50% of the time

Question 23

Difference threshold

Answer 23

minimum difference in physical energy between two stimuli that can be detected 50% of the time

Question 24

three characteristics of light that are processed by the eye

Answer 24

1. Hues - various colours of light red, organic, yellow, green, blue, violet, indigo all relate to a wavelength picked up by the eye
2. Saturation - is a very pure form of color, intense color fire truck red is more saturated than brick red
3. Amplitude - or height of light waves. Taller or have a greater amplitude will appear brighter in intense high-energy illumination and more dull and drab in dim light

Question 25

ccommodation in the eye

Answer 25

Accommodation is changes in the shape of the lens to enable the seeing close and far objects

Question 26

transduction in the eye

Answer 26

Photoreceptors in the retina work with rods and cones

Question 27

Trichromatic and opponent process theories of color vision

Answer 27

Trichromatic color theory - three types of cones most sensitive to red green blue
Opponent-color theory - which states that vision analyzes colors into “either or” messages. Red or green, yellow or blue, black or white

Question 28

Conductive hearing loss

Answer 28

when the transfer of vibrations from outer to inner ear weakens

Question 29

Sensorineural hearing loss

Answer 29

damages to the inner nerve and auditory nerve

Question 30

Frequency theory

Answer 30

as pitch rises, nerve impulses of a corresponding frequency are fed into the auditory nerve are 1,200 hertz produces 1,200 nerve impulses - can go to 4,000 hertz

Question 31

Place theory

Answer 31

the higher and lower tones excite specific places in the cochlea

Question 32

Transduction in the nose

Answer 32

chemical energy is picked up by the nose and turned into electrical energy. When fibres in the nose are stimulated it creates an action potential

Question 33

transduction on the tongue

Answer 33

Taste buds, clusters of taste receptors, when food is chewed chemical molecules enter the tast buds where they set of action potential

Question 34

Monocular depth cues

Answer 34

one eye, perceptual features that impart information about the distance and 3D space that requires one eye. Examples like threading a need, shooting a gun

Question 35

Binocular depth cues

Answer 35

perceptual features that impart information about the distance and 3D space that requires both eyes. Examples playing catch, judging a distance under 50 feet