seizures Flashcards
what is surround inhibition ?
focuses neuronal activity in the CNS
What 2 events characterize seizure inititation?
high-frequency bursts of AP
hypersynchronization
What causes the loss of surround inhibition and and propagation of seizures?
increasing extracellular potassium, accumulation of calcium in presynaptic terminals, depolarization induced activation of the NMDA receptor
What can cause seizure termination?
loss of ionic gradients
depletion of ATP
depletion of neurotransmitters
What is status epilepticus?
a seizure lasting more than 5 minutes or more than 1 seizure in 5 minutes
What is the postictal period?
after seizure 5-30 mins
drowsiness confusion etc
What are focal seizures?
simple or complex
jacksonian march
automatisms
What is a simple vs complex seizure
simple = retain consciousness complex = loss of consciousness
What are generalized seizures?
loss of consciousness
what is a tonic clonic seizure
sustained contractions followed by periods of contraction and relaxation
what is a myoclonic seizure
brief shock like contraction
what do non-convulsive seizures include?
absence
atonic
what are absence seizures?
abrupt onset of impaired consciousness
what is atonic seizures
sudden loss of muscle strength
How do benzodiazepines work?
increase the frequency at which GABA receptor opens (increasing potency of GABA)
positive allosteric modulator
does not act if no GABA present
