Recognition and failures (Lect 8)

Question 1

Lissauer (1890)

Answer 1

Patient GL

• felt unfamiliar with things around his room after accident
• specific to visual object recognition
• this lead lissauer to study more patients and called it: mind blindness with two reoccurring types

Question 2

Apperceptive Agnosia

Answer 2

damage to unilateral RH, right inferior parietal lobe

cannot:
- identify
- match by appearance or function
- copy drawings

–> perceptual problem

Question 3

Associative agnosia

Answer 3

usually bilateral damage to both hemispheres, crucial is LH and more ventral
cannot:
- identify
- match by function
- draw from memory

–> semantic problem (naming and identifying)

Question 4

Warringtons anatomical model (1985)

Answer 4

• proposed a 2-stage model based on agnosia

           LH                                RH
   Associative                  Apperceptive (Can access perception    (cannot access meaning) but cannot figure out        But direct access to meaning what it is).                           
  
    Semantic

Question 5

Information faces gives us:

Answer 5

• layout
• structure
• holistic
• global
• local

Question 6

Paradolia

Answer 6

Seeing faces in objects

Question 7

Study on global and local information

Answer 7

Schwaninger et al. (2002)

• rearranged faces for familiar and unfamiliar faces
• were able to recognize scrambled and blurred faces just fine but not scrambled and blurred together

Question 8

Structures in brain to recognize faces

Answer 8

Right Fusiform Gyrus (aka Fusiform Face Area)

Question 9

Prosopagnosia

Answer 9

Failure to recognize faces

• range of severities
• from: can’t think of the name to cannot recognize a face as a face

Question 10

Prosopagnosia without agnosia

Answer 10

Easier to find cases
Patient WJ:
- became farmer and bought sheep after stroke
- could recognize sheep just fine but face recognition was impaired
Patient RM:
- damage to right hemisphere
- lost ability to recognize faces but could still recognize cars

Question 11

Agnosia without Prosopagnosia

Answer 11

Harder to find
Patient MH:
- naming line drawings was severely impaired
- facial recognition just fine

Question 12

Double dissociation

Answer 12

2 individuals who have opposing problems
Patient MX
- lost ability to recognize faces but after 6 months it came back
- cow recognition impaired

Patient Mr W.

• poor face recognition
• cow recognition intact

Question 13

Is right fusiform gyrus really dedicated to recognizing faces?

Answer 13

• sometimes FFA is still intact with prosopagnosia

- cartoon faces and catscan activate FFA as much as human faces : Tong et al. (2000)

Question 14

Faces just an expertise form of object recognition evidence=

Answer 14

Gauthier et al (1999): created set of creatures with characteristics

• trained ppl to recognize these creatures
• before training: FFA not activated
• after training: FFA activated

–> this suggests that Right fusiform Gyrus is not just about processing faces but just about the expertise

Question 15

Counter argument agains FFA is just expertise

Answer 15

McKone et al (2007) argue that most papers fail to replicate these findings