Consciousness

Question 1

Two components of consciousness

Answer 1

Arousal

Awareness

Question 2

System required for arousal

Answer 2

Ascending reticular activating system

Question 3

Neurones which promote sleep when active

Answer 3

Ventrolateral preoptic area of the hypothalamus

Question 4

Model that suggests when ARAS is active, VLPO is silent and the person is awake; and when VLPO is active, ARAS is silent and the person is asleep

Answer 4

Flip flop model

Question 5

Hypothalamic neurotransmitters which promote wakefulness

Answer 5

Orexins/hypocretin

Question 6

Disorder where a deficiency of orexins is found

Answer 6

Narcolepsy

Question 7

Function of ARAS in relation to the EEG

Answer 7

Desynchronise the EEG to suppress slow waves and potentiate gamma waves

Question 8

State where someone appears to be asleep but may become alert with vigorous stimulation

Answer 8

Stupor

Question 9

Two main types of stupor

Answer 9

Organic

Psychiatric - catatonia

Question 10

Test used to differentiate between organic and psychiatric stupor

Answer 10

Caloric testing

Question 11

Eye movements seen on caloric testing in organic stupor

Answer 11

Deviation but no following nystagmus

Question 12

Eye movements seen on caloric testing in psychiatric stupor

Answer 12

Nystagmus following initial deviation

Question 13

Process of caloric testing

Answer 13

Water is irrigated into the external auditory canal
Water is either cold or warm
If cold water and healthy patient there will be nystagmus to the ipsilateral ear
If warm water and healthy patient there will be nystagmus to the contralateral ear

Question 14

State where someone is unable to speak or move, but alertness appears intact and sleep/wake cycles continue

Answer 14

Akinetic mutism

Question 15

Classical clinical finding on akinetic mutism

Answer 15

Absence of spasticity or rigidity

Question 16

Lesions and diseases causing akinetic mutism

Answer 16

Thalamic stroke
Bilateral cingulate damage
Final stages of CJD

Question 17

State where someone has partial arousal but no awareness

Answer 17

Vegetative state

Question 18

Clinical finding that can differentiate a vegetative state from akinetic mutism

Answer 18

Spasticity and rigidity of the limbs is present in a vegetative state

Question 19

Differences between vegetative state and coma

Answer 19

Patients in a coma have no arousal; patients in a vegetative state have partial arousal
Patient in a vegetative state may - have basic reflexes, continue wake/sleep cycle, open eyes; patients in a coma will not
Patients in a vegetative state usually would not require breathing or circulation support

Question 20

Pathological cause of vegetative state

Answer 20

Intact ARAS and thalamus with significant cortical damage

Question 21

Features of locked in syndrome

Answer 21

Total paralysis below the level of the third cranial nerve nucleus
Ability to open eyes voluntarily
Ability to move eyes vertically voluntarily but not horizontally