10 - The Limbic System

Question 1

Blood supply to the limbic system

Answer 1

Anterior and Posterior Cerebral Artery

tip of the temporal lobe & orbital cortex may be supplied by MCA

Question 2

Function of the limbic system

Answer 2

Pleasure pain, learning and memory

Question 3

Anterior Cingulate Cortex

Answer 3

Activated during pain/depression

Question 4

Caudal anterior cingulate

Answer 4

Quality of pain

Question 5

Rostral anterior cingulate

Answer 5

What actions you do to deal with the pain

Question 6

Parabrachial nucleus to the

Answer 6

Amygdala

Question 7

ACC and Insula

Answer 7

Unpleasantness of pain

Question 8

Cingulotomy

Answer 8

Cutting through the cingulate gyrus to disrupt fibres passing rostro-caudally through it
Reduces emotional stress of pain

Question 9

Orbitofrontal cortex

Answer 9

How to behave to a threat

how to avoid pain

Question 10

What can cause OCD

Answer 10

Prolonged pressure to make impossible decisions - which orbitofrontal cortex modulates

Question 11

Posterior Cingulate Cortex

Answer 11

Involved in the emotional significance of memories e.g activated when memories about family/friends

Question 12

Parahippocampal gyrus

Answer 12

Acquisition of new memories

Question 13

Hippocampus

Answer 13

Needed to store memories

Spatial map = anchors to a time and place

Question 14

Damage of hippocampus

Answer 14

Anterograde amnesia

inability to transfer memories from STM to LTM

Question 15

Describe Papez’s loop

Answer 15

Cingulate cortex -> parahippocampal gyrus –> hyppocampus –> along fornix –> Mammilary bodies –> Anterior thalamus –> Cingulate cortex

Question 16

Damage to Papez’s loop

Answer 16

Recollective memory - deficits in recall of memory

Question 17

Function of mammillary bodies

Answer 17

Contain olfactory cues that link to memories of places

Question 18

What condition did HM suffer from initially

Answer 18

Epilepsy

Question 19

What occurred in the surgery HM had

Answer 19

disconnected temporal lobes

lost parahippocampal cortex, hippocampus and amygdala

Question 20

What was the outcome of HM’s surgery

Answer 20

Severe anterograde amnesia and mild retrograde amnesia

Question 21

Kluver Bucy Syndrome Symptoms

Answer 21

Oral tendencies
Inc sexual behaviour
Hypermetamorphosis
Loss all sense of fear

Question 22

Cause of kluver bucy syndrome

Answer 22

Bilateral removal of amygdala

Question 23

Amygdala function

Answer 23

Activates the flight or flight response of the sympathetic NS
Stimulates fear and anxiety

Question 24

What tract do the effects of the amygdala flow down

Answer 24

Reticulospinal tract

Question 25

Damage to the amygdala

Answer 25

Unable to judge fearful expressions Misinterpretation of hazardous events - excess risk Decreases ability to recognise emotion and makes it harder to empathise with them

Question 26

What pathway is the accumbens nuclei part of

Answer 26

Mesolimbic dopamine pathway

Question 27

Function of accumbens

Answer 27

Initiation and termination of behaviours that trigger reward pathways (e.g chewing and swallowing)

Question 28

How can you help with addictive behaviours

Answer 28

By blocking dopamine receptors in the accumbens