Introduction to the neuropsychology of memory & perception

Question 1

What does the fact that types of memory can be dissociated from each other mean?

Answer 1

They can be disrupted independently by lesions.

Question 2

What’s episodic memory for?

Answer 2

Specific events

Question 3

What is stored in semantic memory?

Answer 3

Facts

Question 4

What is working memory?

Answer 4

Short term, requires rehearsal.

Question 5

What’s procedural memory?

Answer 5

Motor.

Question 6

What’s declarative memory?

Answer 6

Explicit (episodic and semantic)

Question 7

Describe anterograde amnesia.

Answer 7

• Poor ability to acquire new information.
• Information acquired before damage is relatively spared
• Information in working memory is spared
• Impaired declarative memory
• Non-declarative memory relatively preserved.

Question 8

What is non-declarative memory?

Answer 8

Implicit:

• Perceptual memory (stimuli)
• Procedural memory (motor skills and habits)

Question 9

Where does damage cause anterograde amnesia?

Answer 9

Hippocampus and related structures in the medial temporal lobe.

Question 10

What is the cause of Korsakoff’s syndrome?

Answer 10

• Thyamine (vitamin B1) deficit

- Due to alcoholism, poor diet and impaired absorption of thiamine from intestine.

Question 11

What symptoms does Korsakoff’s syndrome cause to happen to the brain?

Answer 11

Bilateral degeneration of mammilary bodies

Question 12

What are the memory-related symptoms of Korsakoff’s syndrome?

Answer 12

• anterograde amnesia
• retrograde amnesia, severe memory loss
• confabulation, (invented memories which - are then taken as true due to gaps in memory sometimes associated with blackouts)

Question 13

Describe the temporal lobotomies carried out in the 1950s.

Answer 13

• For patients with intractable seizures.

- Bilateral removal of temporal lobes.

Question 14

What was surgically removed in HM’s case?

Answer 14

Anterior hippocampal regions (bilateral)

Question 15

What deficits did HM suffer from?

Answer 15

• Inability to form new memories - complete absence of episodic memories, no new semantic memories.
• Temporally graded retrograde amnesia

Question 16

What remained unaffected in HM after the surgery?

Answer 16

IQ, personality, working memory (digit span, rate of forgetting - although had to rehearse constantly), ability to hold a conversation, procedural memory (Milner, mirror tracing task).

Question 17

What is the role of the hippocampus in memory?

Answer 17

• HM suggests memories aren’t stored there.

- Perhaps enables consolidation of memories for transfer elsewhere?

Question 18

How did Marsien-Wilson and Teuber (1975) test HM’s retrograde amnesia?

Answer 18

Photos of celebrities - spanned decades, most distant preserved.

Question 19

What are double dissociations?

Answer 19

• Two patient groups with different lesion sites and impairments.
• Suggest tasks rely to some extent on different brain structures.

Question 20

Why are double dissociations particularly useful?

Answer 20

• Solve problem of task difficulty from dissociations.

Question 21

Define agnosia.

Answer 21

• Lack of knowing/perception - inability to recognise objects.
• Can be visual, auditory, somatosensory.
• Is modality-specific.
• Not due to deficit in ‘early’ perception.

Question 22

What is apperceptive agnosia?

Answer 22

• Inability to perceive a whole object.
• Intact low-level perception, but unable to extract global structures.
• Evidenced by impairments in drawing, copying and recognition.

Question 23

What is associative agnosia?

Answer 23

• Ability to perceive and copy a shape but not name it.
• Inability to draw from verbal instruction or to recognise object using vision.
• Man who mistook his wife for a hat.

Question 24

What is the theoretical explanation for associative agnosia?

Answer 24

• Disconnection between visual representation and language
• Damage includes left occipital cortex and white matter
• Patients can use visual representations to guide non-speech movements, e.g. gestures.

Question 25

What is prosopagnosia?

Answer 25

Inability to recognise faces visually - can tell it’s a face and describe it but not identify.
Can still identify people through other features.

Question 26

What sort of brain damage is usually associated with prosopagnosia?

Answer 26

Right sided damage to the fusiform gyrus in the inferior part of the occipital/temporal lobe.

Question 27

What is the Fusiform Face Area (FFA)?

Answer 27

• Specific area activated by faces (Kanwisher et al., 1997 - imaging).

Question 28

In what ways are we experts at processing faces?

Answer 28

• Can detect subtle emotions
• Can identify individuals despite radically different conditions etc.
• Can identify people despite all faces being pretty similar.

Question 29

What does face processing involve?

Answer 29

Perception of both configuration and features. Holistic processing = FFA?

Question 30

What is the inversion effect?

Answer 30

Upside-down faces are more difficult to recognise - it’s difficult to process feature configuration.
Perhaps upside-down faces don’t use the specialised face-processing system.
Only notice distortion right way up e.g. Thatcher effect.

Question 31

Prosopagnosia suggests that faces are special, but this is a dissociation. In fact,…

Answer 31

Prosopagnosics tend to have difficulty recognising other things too (pure prosopagnosics are rare), faces are just difficult. This suggests that The FFA isn’t only concerned with faces.

Question 32

What did Gauthier et al (1999; 2000) find about the FFA?

Answer 32

It’s activated when experts observe the object of their expertise.

Question 33

Why are pure prosopagnosics so rare if faces are special?

Answer 33

• Accidental lesions are rarely high focal.

- Imaging provides converging evidence and can only say an area’s active during, not necessary for, a function.

Question 34

The idea that faces are special, with dedicated processing systems, is…

Answer 34

Controversial.