NS 10: Consciousness and its disturbances Flashcards
change in neurohormone levels associated with depression?
low levels of serotonin and noradrenaline
change in neurohormone levels associated with Alzheimer’s Disease?
destruction of ACh secreting cells
change in neurohormone levels associated with schizophrenia?
excessive dopamine
waveforms of EEG characterising relaxed wakefulness?
alpha waves= 8-13 Hz
mainly occipital lobe as not receiving any visual stimuli, awake, quiet, eyes shut
waveforms of EEG characterising mental activity, part. from front of brain?
beta waves= >14Hz, higher frequency
awake, eyes open, frontal and parietal lobes
waveforms of EEG characterising 1st stages of sleep, drowsiness?
theta waves= 4-7Hz
parietal and temporal lobes
children, emotional adults
waveforms of EEG characterising deep sleep?
delta waves= <4Hz
mainly cortical
also seen in serious brain conditions
3 reasons as to why disturbance of consciousness may arise?
- metabolic e.g. hypoglycaemia, uraemia or anoxia (no O2)
- brain stem lesions or pressure on brain stem from any SOL causing raised ICP
- head trauma, which may bruise brain within skull
3 sections to glasgow coma scale?
eye opening, 1-4
motor responses, 1-6
verbal responses, 1-5
max and min scores for glasgow coma scale?
max=15
min=3
what has control over the sleep-wake cycle?
reticular formation
hypothalamus- inhibits reticular formation to promote sleep
why do we need sleep?
energy conservation
memory
CNS resetting/clearance
neurohormones characterising waking?
5-HT and noradrenaline constantly active
ACh neurones active during a novel input
neurohormones charactersing non-REM sleep?
5-HT and NA inactive
ACh inactive
neurohormones charactersing REM sleep?
5-HT and NA inactive (memory, without emotion?)
ACh fully active
neurohormones charactersing coming out of REM sleep?
increase NA activity
what is AVPU?
system to assess level of consciousness: A=alert V= responds to verbal stimulus P= responds to pain stimulus U= unresponsive
scores for eye opening with glasgow coma scale?
4= spontaneously 3= to speech 2= to pain 1= none
scores for verbal resonse with glasgow coma scale?
5= orientated 4= confused 3= inappropriate words 2- incomprehensible 1= none
scores for motor response with glasgow coma scale?
6= obeys commands 5= localises pain 4= flexion to pain 3= flexion/withdrawal 2= extension to pain 1= none
what happens in a subfalcal hernia?
part of the cingulate gyrus is forced into space between falx cerebri (inward folding of meningeal layer of dura mater) and the corpus callosum- connects the 2 cerebral hemispheres.