synaptic excitation and inhibition: epilepsy

Question 1

what is the major excitatory NT in the brain?

Answer 1

-glutamate

Question 2

what is the major inhibitory NT in the brain?

Answer 2

GABA

Question 3

what antagonists trigger seizures?

Answer 3

GABA antagonists

Question 4

what antagonists stop seizures?

Answer 4

glutamate antagonists

Question 5

what channel mutation can cause brain hyperexcitability?

Answer 5

mutation of genes encoding voltage / ligand gated ion channels

Question 6

to which part of the brain does damage result in hyper excitable networks

Answer 6

the hippocampus

Question 7

what is a seizure?

Answer 7

transient occurrence of signs and symptoms due to abnormal excessive or hyper synchronous neuronal activity in the brain

Question 8

how are seizures classified?

Answer 8

-into focal and generalised onset

Question 9

what is focal onset seizures?

Answer 9

-these seizures originate in 1 area of the brain
- 2 types - social aware and focal impaired awareness seizures

Question 10

what is a focal aware seizure?

Answer 10

person is conscious during seizure and can recall the event afterwards

Question 11

what is a focal impaired aware seizure?

Answer 11

the person looses consciousness or awareness during the seizure & may have unusual behaviours

Question 12

what are generalised onset seizures?

Answer 12

seizures that involve both hemispheres of the brain

Question 13

what are the different types of generalised onset seizures?

Answer 13

-non motor (absence)
-motor - tonic, clonic, atonic etc

Question 14

what is a motor generalised onset seizure?

Answer 14

a seizure involving changes in muscle activity such as loss of postural tone eg muscle stiffening, jerking etc

Question 15

what is the difference between tonic vs clonic Motor generalised onset seizures?

Answer 15

-tonic - sustained contraction - arching back
-clonic / clonus - rhythmic contraction

Question 16

what are examples of clinical features of a seizure?

Answer 16

NB can vary a lot depending on location and extent of neurons
-disordered thought
-temporary confusion
-loss of consciousness
-urinary incontinence
-eyes rolling etc

Question 17

what is status epilepticus?

Answer 17

-A seizure that lasts longer than 5 minutes, or having more than 1 seizure within a 5 minutes period, without returning to a normal level of consciousness between episodes

Question 18

what effect do epileptic seizures have ion the brain?

Answer 18

-can injure the brain
-altered gene expression
-inflammation
-cell death and gloss

Question 19

what is an EEG?

Answer 19

an electroencephalogram
-records activity generated by the brain

Question 20

what can brain imaging eg MRI help to diagnose?

Answer 20

-structural abnormalities
-functional abnormalities

Question 21

what is epilepsy?

Answer 21

a brain disorder in which a person has recurring seizures
- at least 2 unprovoked seizures occurring more than 24 hrs apart

Question 22

what is epilepsy syndrome?

Answer 22

An epilepsy syndrome is a type of epilepsy that is identified by a specific seizure type or types and by the findings on an EEG

Question 23

what are unknown onset seizures?

Answer 23

-seizures where the precise origin or onset within the brain cannot be determined with certainty.
- In these cases, there may not be enough clinical information, EEG data, or imaging studies to confidently classify the seizure as focal or generalized.