The Limbic System: Part 2

Question 1

what is working memory and give 2 scenarios when it is used

think conscious ability for part 1 of question

Answer 1

1. Conscious ability to manipulate information held in short-term memory
2. Used in:
   - Problem solving and reasoning
   - awareness of emotional and social cues during conversation

Question 2

what is short term memory

Answer 2

• recalled minutes or hours after a stimulus

Question 3

What is working memory controlled by?

Answer 3

• Controlled by lateral prefrontal cortex (frontal lobe) and association areas of temporal and parietal lobes.

Question 4

What is long-term memory

Answer 4

• Events recalled weeks, months or years after a stimulus with structural changes in neurons (i.e protein synthesis, increased synaptic strength, increased neuronal excitability)

Question 5

What is declarative (explicit) memory and define the 2 types of it

think words

Answer 5

1. Means it can be put into words
2. Two types:
   - semantic memory: common knowledge (i.e: who is the prime minister)

• episodic memory: personal experiences (eg: a party you attended)

Question 6

What is non-declarative memory and what is a type of non-declarative memory and define it

think muscle memory

Answer 6

1. semi-automatic learning
2. Type of non-declarative memory:
   - procedural memory: learning and performing motor skills (muscle memory)

Question 7

What is amnesia and what are the 2 types of it.

Answer 7

1. Loss of declarative memory
2. Two types:
   - retrograde amnesia: unable to remember events from before an injury
   - Anterograde amnesia: unable to remember new events after an injury

Question 8

What is unaffected and what is affected in amnesia

think tasks, and muscle memory

Answer 8

• Unaffected: procedural memory
• Affected: ability to recall practicing tasks or skills

Question 9

What are the 3 stages of declarative memory

Answer 9

1.Encoding
2. Consolidation
3. Retrieval

Question 10

What is encoding in declarative memory and how is it improved

thing information processing and what this does to memory for first part

think drawing connections for second part

Answer 10

• Processing information into a representation of a memory
• Improved by: paying attention, mood, drawing connections between information

Question 11

What is consolidation in declarative memory and how does it happen

thinks stabilization, synapses and medial temporal lobe

Answer 11

*It is stabilizing of memories

1. Happens by synaptic connections become stronger with repeated activation (long-term potentiation)
2. Medial temporal lobe directs storage of memories across large networks of neurones elsewhere

Question 12

what is an engram

Answer 12

an engram is a group/network of neurones that all fire at the same time when you think of a memory

Question 13

What is Retrieval in declarative memory and how is it important?

think usage of memories for part 1

for part 2 think spaced retrieval practice

Answer 13

• Accessing and using memories in different ways (recall, recognition)
• important for learning (spaced retrieval practice)

Question 14

What does the lateral prefrontal cortex do in memory and what is it involved in?

think working memory for first part
think what lateral prefrontal cortex does for declarative memory for second part

Answer 14

• Keeps working memory “focused”
• Involved in processing and retrieving declarative memory

Question 15

What are association areas in temporal, parietal and occipital lobes involved in

think types of memory and sensory perceptions

Answer 15

• Involved in declarative memory and integrating sensory perceptions

Question 16

What can bilateral lesions of anterior hippocampus cause?

Answer 16

Can cause anterograde amnesia

Question 17

What does the posterior hippocampus help with

think type of storage and what it DOESNT help with

Answer 17

Helps to encode memories for long-term storage elsewhere but does NOT help with recall

Question 18

what does the left hippocampus help with

Answer 18

Helps to encode verbal memories

Question 19

What does the right hippocampus help with

Answer 19

Helps to encode spatial memories

Question 20

What artery supplies the hippocampus

Answer 20

Anterior choroidal artery branches

Question 21

What expands in the brain in Alzheimer’s disease?

Answer 21

Lateral ventricle expands

Question 22

Where does the cingulate cortex receive information

think position of this nucleus in thalamus and also fibres

Answer 22

Receives information from anterior nucleus of thalamus via projecting fibres

Question 23

What 7 things is the cingulate cortex involved in?

think insular cortex, pain and emotions, memory, Auto something, bladder, CEOs (like the business man), mood

Answer 23

1. linking to insular cortex - self awareness and interoception
2. pain perception and emotional regulation
3. learning and memory
4. autonomic areas
5. bladder control
6. speech
7. executive function
8. mood disorders (Most important one) like depression

Question 24

What blood vessel supplies the cingulate cortex?

Answer 24

anterior cerebral artery

Question 25

Where is amygdala located

think lobes

Answer 25

More anteriorly in medial temporal lobe

Question 26

what 4 things is amygdala involved in

think fear, pathways, food and sex

Answer 26

1. Processing fear or stressful stimuli
2. autonomic and endocrine pathways
3. appetite
4. regulating sexual restraint

Question 27

What 2 things is the nucleus accubens involved in?

think types of behaviors and types of learning it encourages

Answer 27

1. Role in addictive behaviours (eg gambling)
2. Encourages motivation, reward-based learning

Question 28

What is septal nuclei involved in and what can lesions here cause?

think type of behavior for second part

Answer 28

• Roles in pleasure, social connection and empathy
• Patients with lesions can display antisocial behaviour

Question 29

What is Wernicke-Korsakoff Syndrome and what does it lead to?

think inflammation of tissues around brain for first part

for second part think vision, discumbobulation and coordination

Answer 29

• It is a syndrome caused by Wernicke’s encephalopathy (chronic inflammation of tissues around the brain),
• leads to acute confusion, loss of coordination and gaze paralysis (ophthalmoplegia)

Question 30

What can cause Wernicke-Korsakoff syndrome and what environmental factors can increase the risk of this?

think mammillary bodies and hippocampi for first part

think alcohol and what specific vitamin deficiency this causes for part 2

Answer 30

• Small haemorrhages in mammillary bodies and damage to connections with hippocampi
• These haemorrhages can be increased in risk by environmental factors like chronic alcoholism as this causes vitamin B1 (thiamine) deficiency

Question 31

What can repeated episodes of wenicke-Korsakoff syndrome cause and what are 2 symptoms of this?

Answer 31

1. Can cause Korsakoff’s psychosis
2. Symptoms:
   - anterograde amnesia
   - confabulation (patient creates fictional memories believing they are real)

Question 32

What is kluver-Bucy syndrome

think lesions of lobes and destruction

Answer 32

1. Bilateral (both sides) temporal lobe lesions E.g bilateral stroke, traumatic brain injury, neurodegenerative disorders
2. Also bilateral destruction of amygdala

Question 33

What are 4 symptoms of Kluver-Bucy syndrome?

think objects in mouth, abscense of fear/aggression, loss of restraint of something and difficulty recognizing certain things

Answer 33

1. Hyperorality (compulsioni to put objects in mouth)
2. Placidity – fear and aggression may be absent
3. Hypersexuality – loss of restraint
4. Visual agnosia - difficulty recognizing familiar objects/faces