Chapter 11- Visual Knowledge

Question 1

Self-Report Data:

Answer 1

• Asked people to describe their mental images and rate them for vividness
Wide range in self reports (some very clear, others vague sketches)

Question 2

Chronometric Studies:

Answer 2

• Allow us to ask what sort of information are prominent in a mental image by measuring time of response
• i.e. Participants asked to form mental images and answer yes/no questions about each. “Does the cat have a head” produced faster responses than “Does the cat have claws”
When participants asked to think about cats rather than picturing them, the question “Does the cat have claws” produced faster responses

Question 3

Image Scanning Procedure:

Answer 3

• Participants asked to form image of a landmark, and asked to imagine a black speck moving from the first landmark to the second
• When the speck reached the target, participants pressed a button
• Measure of how long participants needed to “scan” between landmarks
• Participants scan across images at a constant rate
Similar results occur when participants asked to “zoom in “ on their images (response time proportional to amount of zoom

Question 4

Depictions:

Answer 4

• Images depict a scene rather than describe it
• More similar to pictures or maps than to descriptions
Spatial layout conserved

Question 5

Mental Rotation:

Answer 5

• Participants asked to decide whether a display showed 2 different shapes or one shape from 2 different perspectives
Participants first imagine one of the forms rotating into alignment with the other, then make a decision

Question 6

Demand Character:

Answer 6

• Cues that might signal how participants are “supposed” to behave in the experiment
i.e. waiting to press the button because they know experimenter is looking for a long scan time

Question 7

Imagery and Perception- Interference:

Answer 7

• Participants asked to detect faint signals (dim lights or soft tones), asked to determine whether stimuli was present while forming a visual imagine before “mind’s eye” or while forming an auditory image before “mind’s ear”
• If there is overlap between imaging and perceiving, then interference should occur if participants try to do both activities at once
Forming visual image interferes with seeing, forming auditory image interferes with hearing

Question 8

Imagery and Perception- Facilitation:

Answer 8

• Participants asked to form H or T
• Faint H or T then presented (hard to perceive because very faint)
Perception was facilitated if participants had been visualizing target form (Visualizing H made it easier to perceive H)

Question 9

Binocular Rivalry:

Answer 9

• 2 different visual stimuli are presented, one stimulus to each eye
• Visual system unable to combine inputs, end up being aware of just one of the stimuli for a few moments, then aware of the other stimuli for a little bit…etc
If pattern is visualized first, it is most likely to dominate (be perceived earlier and for more time)

Question 10

Visual Imagery and the Brain:

Answer 10

• Occipital lobe activated during visualization

Areas in brain highly sensitive to motion also activated when asked to imagine movement

Question 11

Decoding:

Answer 11

• Participants asked to create and maintain a visual image while investigators record brain activity
fMRI analyzed mathematically, can figure out what participants were visualizing by comparing patterns between visualizing and seeing

Question 12

Visual Imagery and Brain Disruption-TMS:

Answer 12

• Transcranial magnetic stimulation (TMS) creates series of strong magnetic pulses that creates temporary disruption in brain region
Disrupting Area VI (where axons from where axons from visual system first reach occipital cortex) results in problem with visual imagery

Patients with brain damage that can’t perceive colour also can’t visualize in colour

Question 13

Visual Imagery and Brain Disruption- Brain Damage:

Answer 13

Patients who lost ability to perceive fine detail also can’t visualize fine detail

Question 14

Neglect Syndrome and Visualization:

Answer 14

• Spatial imagery (i.e. image scanning, mental rotation) represented in the mind in terms of a series of imagine movements
• Suggests that spatial imagery is not tied to sensory info, but to broader cognition about spatial arrangements and layouts
• Brain areas activated for visual tasks are different from those activated by spatial tasks
Brain damage to visual areas won’t interfere with spatial imagery, vice versa

Question 15

Eidetic Imagery:

Answer 15

• Photographic memory

Individuals can briefly glance at a complex scene and draw incredibly detailed reproductions of the scene

Question 16

Percepts:

Answer 16

• Mental representations of stimuli being perceived
• Similar to pictures- depictions, not descriptions
• Different to pictures- organized and unambiguous
i.e. Perception of necker cube not neutral

Question 17

Reinterpreting Visual Images:

Answer 17

• Participants shown an ambiguous picture (i.e. duck or rabbit)
• Asked to visualize image and reinterpret it, but couldn’t (couldn’t find duck in rabbit image or vice versa)
• Asked to draw image, then were able to reinterpret it
Images are inherently organized, just like percepts are

Question 18

Image Information in Long Term Memory:

Answer 18

• To form an image, first have to activate nodes specifying “image frame”, then details can be added
Images containing more parts take longer to create

Question 19

Image Files:

Answer 19

• Files in LTM that contains information needed in order to create a mental image
Image files contain instructions for creating an image

Question 20

Verbal Coding of Visual Materials:

Answer 20

• In some cases, visual information is stored as a proposition/ verbal label
• i.e. Participants told figure was either “eyeglasses” or “barbell”, when asked to redraw it, they distorted the drawing according to the label
i.e. Montreal is in Canada, Seattle is in the US, therefore Montreal must be farter north than Seattle

Question 21

Imagery and Memory:

Answer 21

• Imagery improves memory
• Participants presented with a list of nouns and asked to rate how readily it evokes and image
• i.e. “elephant” was higher on the list, “virtue” was lower
New participants asked to memorize list of words, found that high imagery words more readily learned

Question 22

Dual Coding:

Answer 22

• Imagery provides means of organizing materials, organization helps memory
• High imagery words likely doubly represented in memory (word and picture)
• Results in double that chance of locating information needed
2 types of memory- symbolic and image based

Question 23

Memory For Pictures:

Answer 23

• Visual memory heavily influenced by schema based, generic knowledge
Participants shown a picture of a kitchen with out of place objects (i.e. a fireplace), when shown a new picture and asked if it is the same picture they were shown, they can tell that it is a different picture

Question 24

Boundary Extension:

Answer 24

• People remember a picture including more than it actually did
• Participants shown picture of a fence (tips not shown), when asked draw, participants drew the tips of the fence
People understand picture by means of a perceptual schema, that places picture in a larger context