7.2: The Reticular Formation Flashcards
What is the reticular formation?
A specialised population of interneurones in the brainstem that mediates our overall level of consciousness
What are the 3 categories tested in the Glasgow coma scale?
Eye opening response
Verbal response
Motor response
What are the maximum scores for each section of the Glasgow coma score responses?
Eye opening response scored out of 4
Verbal response score out of 5
Motor response scored out of 6
The Glasgow coma score for a comatose patient will be less than what?
8 or less
What does an EEG measure?
The activity of thousands of neurones in the cortex to assess consciousness
What type of feedback loop exists between the cortex and reticular formation?
Positive feedback loop
Where is the reticular formation?
In the brainstem
What neurotransmitter does the reticular formation use to send its excitatory signals?
ACh
Hence why antimuscarinics make you feel drowsy
Why do some antihistamines induce drowsiness?
Inhibits histaminergic excitiation from the hypothalamus to the cortex for the maintenance of consciousness, so positive feedback loop is weaker
What happens to the frequency and amplitude of the EEG waves as we go from the awake stage down to the stage 4 phase of sleep?
Decreases in frequency but increase in amplitude
How many cycle of sleep do we typically pass through in a night?
6 cycles
