T1 L12: Neurophychology of memory

Question 1

Who was patient HM?

Answer 1

Henry Molaison who suffered from treatment-resistant epilepsy. His seizures were localised in the temporal lobe so he had a bilateral medial temporal lobectomy including the hippocampus in the 1950’s. His seizures stopped but he was unable to form new long-term memories

Question 2

What is Retrograde amnesia?

Answer 2

An inability to recall previously learned information or past events

Question 3

What is Anterograde amnesia?

Answer 3

The inability to remember new information

Question 4

What is Ribot’s Law?

Answer 4

That the most recently acquired memories are the most vulnerable to disruption from brain damage. This can be observed in retrograde amnesia

This is because new memories haven’t had time to consolidate yet

Question 5

What is a temporal gradient?

Answer 5

A pattern of retrograde amnesia characterized by greater loss of memory for events from the recent past (Ribot’s law)

Question 6

What is Declarative memory?

Answer 6

A type of memory that requires conscious recollection Eg. Episodic memory and semantic memory

Question 7

What is semantic memory?

Answer 7

Facts, Knowledge, and language

Question 8

What is Non-declarative memory?

Answer 8

A type of memory that doesn’t require conscious recollection Eg. Procedural, Perceptual representation system, Classical conditioning, and nonassociative learning

Question 9

What is the perceptual representation system?

Answer 9

A memory system whose function is to identify objects and words, allowing quick recognition of previously encountered stimuli

Question 10

What is nonassociative learning?

Answer 10

Instances in which an animal’s behaviour toward a stimulus changes in the absence of any apparent associated stimulus or event (such as a reward or punishment)

Question 11

What type of memory is typically affected by anterograde amnesia?

Answer 11

Episodic memories

Question 12

What is the 2-stage theory of memory consolidation?

Answer 12

1. Initial encoding
   New information processed to hippocampus
2. Consolidation
   Neocortex receives information from the hippocampus for permanent storage of information. Sleep is important for this

Question 13

What is the dedicated brain system for procedural memory?

Answer 13

The basal ganglia

Question 14

Which memory system does Huntington’s disease impair?

Answer 14

Procedural memory by impairing the basal ganglia

Question 15

What are the causes and symptoms of Wernicke’s Encephalopathy?

Answer 15

Triad of impairments: Acute confusion, ophthalmoplegia/ Nystagmus, and ataxia

Caused by a thiamine (B1) deficiency

Question 16

What are the 3 possible outcomes that develop after Wernicke’s Encephalopathy?

Answer 16

Minor to no cognitive sequalae (12%)
Korsakoff’s syndrome (68%)
Death (20%)

Question 17

What is confabulation?

Answer 17

False or erroneous memories without the intention to deceive. They can be jumbles up in the temporal cortex or retrieved inappropriately

It’s common in Wernicke’s-Korsakoff’s syndrome

Question 18

What is spontaneous confabulation

Answer 18

Persistent and unprovoked. The memories can be bizarre in content

Question 19

What is Momentary/provoked confabulation?

Answer 19

Errors or distortions in memory that arise in response to a challenge to memory like a memory test

Question 20

What is semantic dementia?

Answer 20

A progressive loss of conceptual knowledge and understanding of the world. It’s not to one modality Eg. confusing doorbell and telephone

Question 21

What are the symptoms of behavioural-variant frontotemporal dementia (bvFTD)?

Answer 21

• Changes in social conduct and behaviour
• Loss of empathy
• Apathy
• Disinhibition
• Lack of insight

Question 22

What is ophthalmoplegia?

Answer 22

Also called extraocular muscle palsy, paralysis of the extraocular muscles that control the movements of the eye

Question 23

What is Nystagmus?

Answer 23

An involuntary rhythmic side-to-side, up and down or circular motion of the eyes

Question 24

What is ataxia?

Answer 24

Lack of coordination

Question 25

What are the symptoms of Semantic dementia (SD)?

Answer 25

• Loss if semantic knowledge
• Impaired word comprehension and object naming
• Fluent speech with spared repetition

Question 26

What are the symptoms of Progressive non-fluent aphasia (PNFA)?

Answer 26

• Apraxia and effortful speech

- Spared knowledge and word comprehension

Question 27

Which hemisphere is most affected by semantic dementai?

Answer 27

The left hemisphere (the language dominant area)

Question 28

Which processes are impaired in semantic dementia?

Answer 28

Confrontation naming, word comprehension, Object recognition, autobiography memory (reverse temporal gradient), future thinking, emotion perception and empathy, theory of mind

Question 29

Which processes are relatively preserved in semantic dementia?

Answer 29

Episodic memory, navigation, visuospatial ability, attention, processing speed, phonology and syntax, non-verbal problem solving