Epilepsy Seizures Flashcards
What happens in the tonic phase?
Muscles stiffen, person falls to floor
What types of seizures are classed as primary generalised seizures?
Tonic clonic grand mal
Absence petit mal
Tonic, atonia and myoclonic
These seizures involve the whole cortex on both sides of your brain
What happens in clonic phase?
Jerking of limbs and body occurs
What happens in a myoclonic seizure?
Jumps and jerks
Sudden muscle contractions
What happens in an atonic seizure?
Person goes floppy and falls like a puppet, very brief
What is a secondary generalised seizure?
Small seizures leading to big seizure, slowly progressing
Partial focal seizure (in a localised part of the brain) may go on to develop into the big, secondary seizure
How can partial seizures be further divided?
Simple: no loss of consciousness
Complex: loss of consciousness
Remember primary generalised seizures always lead to a loss of consciousness
In a tonic clonic grand mal seizure, where does the discharge of electrical activity start?
Starts in temporal lobe of the cortex then sets fire to the whole cortex by the tonic phase
What’s the post ictal phase of a tonic clonic seizure?
The recovery phase straight after
Person feels sick and groggy
3 areas of the brain most susceptible to abnormal brain activity?
All part of temporal cortex:
Hippocampus, entorhinal cortex, amygdala
What do epileptic patients have a shortage of?
Inhibitory gaba interneurones
These usually act to stop excitation running away with itself
They sit between excitatory neurones and stop excitation becoming too much.
Loss of inhibiton can lead to epilepsy
Increased excitation can lead to epilepsy
How do anticonvulsant drugs block a sodium channel?
They bind to and hold the channel in its INACTIVE state!! So the channel cannot open, stops any further action potentials being generated, they will allow ONE ACTION POTENTIAL through so that neurones can talk to EACHOTHER.
What drugs block sodium channels and are therefore anticonvulsants?
Phenytoin
Carbamazepine
Lamotigine
Sodium valproate
Drugs that block calcium channels?
Ethosuximide
Gabapentin
