Neuropsychology of memory

Question 1

What is amnesia?

Answer 1

Intelligence is intact
Attention span is intact - short term memory working processes
Personality is unaffected
Ability to take in new information is severely and usually permanently affected
Phonological store and visuospatial sketchpad unaffected
Double dissociation with patients with impaired STM

Question 2

What was significant about the events that happened to HM?

Answer 2

Underwent surgery for the treatment of severe epilepsy. Removal of bilateral medial temporal lobes and hippocampus
Completely lost his memory for events after surgery
Could not recall ever having met the specialists he had been talking to after they left the room for a few minutes

Question 3

Which areas of the brain are involved in amnesia?

Answer 3

Damage to medial temporal lobe or anatomically connected regions

Question 4

What may cause amnesia?

Answer 4

Can occur in head injuries, alzheimer’s disease, epilepsy and stroke

Question 5

What does anterograde mean?

Answer 5

After brain injury occurs

Question 6

What is anterograde amnesia?

Answer 6

Anterograde episodic memories are severely affected

Question 7

How is the long term memory divided?

Answer 7

Declarative (conscious) - Episodic (Personal events) and semantic (knowledge and facts)
Implicit (not conscious) - priming effects and procedural memory

Question 8

What can amnesics still do?

Answer 8

Learn new skills - independent procedural memory

Question 9

What is the procedural memory?

Answer 9

Learning of motor skills, distinct from explicit long term memory
When skills become automatic, they can operate in the absence of awareness

Question 10

Which brain systems are dedicated for procedural memory?

Answer 10

Basal ganglia

Question 11

When is procedural memory inhibited?

Answer 11

Huntington’s disease

Question 12

Which part of the long term memory is unaffected by anterograde amnesia?

Answer 12

Implicit (not conscious)

Question 13

Which part of the long term memory is affected by anterograde amnesia?

Answer 13

Declarative (conscious)

Question 14

What is episodic memory?

Answer 14

Memory for events and occurrences that are specific in time and place

Question 15

What is semantic memory?

Answer 15

Knowledge of facts, concepts, word meanings etc

Can be retrieved without knowledge about where and when the information was acquired.

Question 16

What is the declarative memory theory?

Answer 16

All declarative memories (episodic and semantic) depend on medial temporal lobes for their acquisition and short-term retention

Question 17

Can new semantic memories be formed despite amnesia?

Answer 17

No however patients with perinatal anoxia have sustained damage to their hippocampus just after birth and have impaired episodic memory however they have had normal schooling and gained knowledge.

New episodic memories are always impaired in anterograde amnesia
Evidence for new semantic learning in amnesia is mixed
At best, learning is limited to certain special situations.

Question 18

What is retrograde amnesia?

Answer 18

Before brain injury
Some degree of retrograde amnesia is almost always present
The extent of retrograde amnesia for episodic memories is highly contested

Question 19

What is declarative memory theory?

Answer 19

All declarative memories (episodic and semantic) depend on medial temporal lobes for their acquisition and short-term retention

Over time, declarative memories become consolidated to other brain regions

Question 20

Is episodic memory for the distant past intact?

Answer 20

Yes in most cases

However some patients it is intact (unilateral temporal lobe epilepsy)

Question 21

What happens to semantic memory and episodic memory in retrograde amnesia?

Answer 21

Semantic knowledge learnt long ago is intact
Evidence for preserved remote episodic memory is mixed
Some patients seemingly show very good recall
But are these memories highly practiced and recalled “by rote”?
Possible differences between patients in lesion location, etc.

Question 22

What does semantic dementia cause?

Answer 22

Poor knowledge of meaning of words or concepts
Naming difficulties
Including semantically related errors (e.g. “dog” for rabbit).
Not confined to one modality
Deficits may include a difficulty in recognizing sounds (e.g. doorbell or telephone)

Question 23

Which area of the brain is semantic knowledge associated with?

Answer 23

Semantic knowledge associated with lateral temporal cortex (on the left side of the brain)

Question 24

What is confabulation?

Answer 24

“erroneous memories, either false in themselves or resulting from ‘true’ memories misplaced in context an inappropriately retrieved or interpreted” Kopelman, 1995.

Question 25

What is provoked confabulation?

Answer 25

Provoked - a normal response to a demand for information which is not available (e.g. saying that items in a test have been shown before when they were not)

Question 26

What is spontaneous confabulation?

Answer 26

Spontaneous – the person acts on their erroneous memories (e.g. tries to leave a hospital because believe they have to go to work or cook a meal)

Question 27

What causes spontaneous confabulation?

Answer 27

Usually a result of frontal lobe damage
Not due to damage to memory storage
Caused by a breakdown in memory “control processes” such as monitoring whether retrieved memories are relevant to now