The Reticular Formation Flashcards
What is the reticular formation?
A population of specialised neurones in the brainstem that control wakefulness.
What are the inputs into the reticular formation?
Sensory system
Cortex
What are the outputs of the reticular formation?
Thalamus- sensory gating
Hypothalamus
Basal forebrain nuclei
Spinal cord (muscle tone)
What 3 areas is the glasgow coma scale measured on?
Eye opening
Motor response
Verbal response
What are the 4 stages of eye opening in the GCS score?
4- spontaneous
3- to speech
2-to pain
1-nil
What are the 6 stages of motor response in GCS score?
6- obeys commands 5-localized 4-withdraws 3-abnormal flexion 2- extensor response 1-nil
What are the 5 stages of verbal response in GCS score?
5-oriented 4-confused conversatino 3-inappropriate words 2-incomprehensible sounds 1-nil
What are the 5 stages of sleep?
Stage 1- theta waves
Stage 2/3- sleep spindles- (thalamus trying to wake you up), K complexes
Stage 4- delta waves
REM sleep- looks like awake state
What is the neural mechanism of sleep?
All about deactivation of reticular activating system and inhibiting thalamus.
What is brain death?
Widespread cortical and brainstem damage. Flat EEG.
What is a coma?
Widespread brainstem and crotical damage with various EEG patterns detectable. Unarousable and unresponsive to psychologically meaningful stimuli. No sleep wake cycles.
What is PVS?
Permanent vegatative state. Widespread cortical damage with various EEG patterns. Like coma but some spontaneous eye opening. Can even localise to stimuli via brainstem reflexes. Sleep wake cycle detectable.
What is locked in syndrome?
Can be caused by basilar/ pontine artery occlusion. Eye movements can be preserved, but all other somatic motor functions lost from pons downwards.
