lecture 8- failures of recognition: agnosia and prosopagnosia

Question 1

what is object recognition?

Answer 1

Object recognition in psychology refers to the cognitive process by which humans identify, categorize, and understand objects in their environment based on sensory input, such as visual or auditory cues. It is a fundamental aspect of perception that allows individuals to navigate and interact effectively with their surroundings.

Question 2

when object recognition fails

Answer 2

• Lissauer (1890) - patient GL
• Freud (1891): agnosia
• modality specific
• can be category specific
• Apperceptive agnosia
• Associative agnosia

Question 3

what are the two types of agnosia

Answer 3

• apperceptive agnosia
• associative agnosia

Question 4

performance in tasks - apperceptive

Answer 4

identify object- no
describe features- yes
match by appearance - no
match by function- no
copy drawings- no
draw from memory- yes

Question 5

performance in tasks - associative

Answer 5

identify object- no
describe features- yes
match by appearance - yes
match by function- no
copy drawings- yes
draw from memory- no

Question 6

copy drawing- apperceptive agnosia

Answer 6

• will really struggle to copy a drawing, but can produce the right elements of some sort

Question 7

copy drawing- associative agnosia

Answer 7

• no problems with copying drawing but fail to name what they are

Question 8

drawing from memory- apperceptive

Answer 8

• they are able to draw from memory

Question 9

drawing from memory- associative

Answer 9

• can copy drawings but cant draw from memory

Question 10

differences in sites of damage

Answer 10

apperceptive agnosia
- the damage tends to be in the right hemisphere and in the right hemisphere alone
- Unilateral right hemisphere damage.
Right inferior parietal lobe

associative agnosia
- the damage tends to be bilateral and in a slightly different area, left hemisphere is the crucial damage in these patients
- Usually bilateral. Crucial area thought
to be left hemisphere. More ventral
than apperceptive damage

Question 11

based on these behaviours and damage Warringtons anatomical model was created (theoretical model)

Answer 11

• initial visual processing in the occipital lobes in the back of their brain, and that information gets passed to something in the right hemisphere where the perceptual categorization goes on. this is taking that raw feature image from the vision and turning it into a three dimensional understanding in the brain, a three dimensional model, thats perceptual categorization
  -once thats complete, and 3 dimensional model is constructed then that information is passed on to the left hemisphere where its linked where the semantic categorization happens thats the bit linking it to your stored knowledge about objects and being able to generate the name of the object
• so idea was that in apperceptive agnosia you get damage that disrupts the perceptual categorisation area and as a result bc the flow of information is disrupted