8.2.4 Consciousness Disorders

Question 1

What is brain death?

Answer 1

Widespread cortical and brainstem damage

Flat EEG

Question 2

What is a coma?

Answer 2

Widespread brainstem and cortical damage

Various disordered EEG patterns

Unarousable and unresponsive to psychologically meaningful stimuli

No sleep-wake cycle detectable

Question 3

What is PVS (persistent vegetative state)?

Answer 3

Widespread cortical damage
Various disordered EEG patterns

Like coma but some spontaneous eye opening

Can localise to stimuli via brainstem reflexes

Sleep-wake cycle detectable

Question 4

What is locked in syndrome?

Answer 4

Caused by basilar/pontine artery occlusion

Eye movements can be preserved, but all other somatic motor functions lost from the pons down