Week 3

Question 1

Frontal lobe

Answer 1

• Motor related functions
• Comprised of a big chunk of the cerebral cortex
• A substantial proportion of each frontal lobe as motor related functions
• M1 = primary motor cortex
• PMA = premotor cortex
• SMA = supplementary motor cortex

Question 2

Primary motor cortex

Answer 2

• Crucial for almost all voluntary movement
• Occupies the precentral gyrus
• Electrical stimulation causes movement of the body
• Different locations associated with different parts – a map
• More specific movement eg hands and face – larger region
• Damage = problems coordinating and controlling muscles in voluntary movement

Question 3

Penfield’s motor homunculus

Answer 3

• Which part of the body moves is dependent on where the brain is stimulated
• The quantity of the cortex that it occupies depends on the body part itself and the amount of cortical control it needs

Question 4

Damage to more rostral motor areas

Answer 4

• Affects planning, selecting and initiating acts

Question 5

Unilateral damage - SMA

Answer 5

• No abnormal ownership or sensory perception
• Abnormal action execution
• Limbs act autonomously and inappropriately for environment
• Deny they perform the acts

Question 6

Bilateral damage – SMA

Answer 6

• Utilisation behaviour
• Spontaneous object - appropriate actions when someone sees an object
• Does not realise behaviour is inappropriate
• Don’t deny that they perform the acts

Question 7

What does SMA damage suggest?

Answer 7

• Frontal cortex – inhibitory control – by lifting this we can perform the action
• If damaged, then we cannot inhibit the action
• Well learned, voluntary behaviours that are directed as external objects have a kind of reflexive (S-R) structure that is normally regulated by volitional processes

Question 8

Anarchic hand syndrome

Answer 8

• Movements are unintended and inappropriate
• Of contralateral upper limb
• Associated with damage to SMA (hand and arm are most effected)

Question 9

Alien hand syndrome

Answer 9

• Anarchic hand accompanied by delusions of ownership

Question 10

Phineas Gage

Answer 10

• Damage was to the prefrontal cortex (lateral orbitofrontal cortex, ventromedial prefrontal cortex)
• Memory and language were fine
• Personality was altered

Question 11

Prefrontal cortex role

Answer 11

• Ability to control impulses, emotions and the urge to satisfy desires
• Ability to plan a course of action to achieve an overall goal
• Ability to maintain concentration when carrying out extended tasks
• Ability to hold information in working memory and retrieve task-relevant information into working memory

Question 12

Autonomic response to threat

Answer 12

• Medicated by sympathetic branch of the ANS
• Increased heart and respiratory rate
• Sweating
• Decreased salivation, digestion in stomach and intestines
• Pupil dilation
• Blood vessel dilation
• Adrenal medulla releases adrenaline – emphasises these

Question 13

Hypothalamus

Answer 13

• Cluster of small nuclei
• Small region of forebrain
• Superior to midbrain
• Controls response to threat
• Controls pituitary gland and SNS

Question 14

Pituitary gland

Answer 14

• CRH is released from the hypothalamus
• This triggers the pituitary glad to release ACTH
• Adrenal gland releases stress hormones (adrenaline)
• Increases energy release
• Suppresses inflammatory response
• Suppresses immune response