Patho of seizures

Question 1

Where/ how do neurotransmitters work?

Answer 1

Work at synaptic cleft, where they either inhibit or excite the neurons

Question 2

Whether a neuron is inhibitory or excitatory is dependent on?

Answer 2

On the receptor they bind to

Question 3

3 key points about receptors

Answer 3

1) they’re proteins
2) match size & shape of neurotransmitter
3) named according to transmitter they bind with

Question 4

Action of transmitters:

Ex. of inhibitory transmitters Hint: 3

Answer 4

1) dopamine
2) serotonin
3) GABA

Question 5

Action of transmitters:

Ex. of excitatory transmitters Hint: 2

Answer 5

1) ACh (Acetylcholine)
2) norepinephrine

Question 6

Where is Acetylcholine (ACh) found in the body?

Answer 6

CNS, PNS, & ANS

Question 7

Is ACh excitatory or inhibitory?

Answer 7

Can be either → depends on neurons secreting it
- PNS → excitatory at neuromuscular junctions
- ANS → inhibitory & slows HR

Question 8

Serotonin (5-hydroxytrptamine) is derive from?

Answer 8

tryptophan

Question 9

Where is serotonin primarily found?

Answer 9

GI tract, PLTs, Brainstem

Question 10

Serotonin contributes to

Answer 10

feeling of well being & mood regulation

Question 11

Where is dopamine located?

Answer 11

mainly in substantia nigra of midbrain/ basal ganglia region

Question 12

List 6 functions of dopamine

Answer 12

1) behavior & cognition
2) voluntary motor movement
3) motivation punishment & reward
4) attention
5) working memory
6) learning

Question 13

List some examples of neuropsychiatric & voluntary motor movement disorders that dopamine is involved in

Answer 13

1) social phobia, ADHD, drug & alcohol dependence
2) Parkinson’s disease
3) Tourette’s syndrome

Question 14

What is the chief inhibitory transmitter in the CNS?

Answer 14

GABA → gamma amino butyric acid

Question 15

What kind of effect does GABA have on the brain?

Answer 15

relaxing, anti-anxiety, & anticonvulsant effect

Question 16

What kind of effect does GABA have on the muscles?

Answer 16

Inhibitory effect → decrease muscle spasms & improved tone

Question 17

What is norepinephrine?

Answer 17

An excitatory neurotransmitter in the brain & stress hormone within endocrine system

Question 18

Norepinephrine plays a role in what response?

Answer 18

Fight or flight response

Question 19

What is glutamate & what is it involved in?

Answer 19

1) major mediator of excitatory signal
2) Involved in cognition, memory, & learning

Question 20

What neurotransmitter plays several roles in both normal & abnormal brain activity?

Answer 20

Glutamate

Question 21

Action potentials are also known as ____ ____ ____

Answer 21

Neuron conduct impulses

Question 22

Action potentials are abrupt changes in what?

Answer 22

Membrane potential which permit nerve signals to be transmitted from the cell body down the axon

Question 23

Action potentials stimulate ____, _____, & _____ ions to move across axon membrane (Hint: electrolytes)

Answer 23

Sodium, potassium, & calcium

Question 24

What are the 3 phases of neuron conduction (action potentials)?

Answer 24

1) depolarization of the neuron = positively charged ion
2) repolarization of neuron = return of neuron to a negative value
3) resting period

Question 25

What can lead to seizures?

Answer 25

Impulses that do not maintain a systematic order (excitatory, inhibitory, & rest phase become irregular & chaotic)

Question 26

Neurons are usually in a ____ charged state

Answer 26

negatively

Question 27

Define seizures

Answer 27

A single episode of abnormal electrical d/c from cortical neurons (too much OR too little) that results in abrupt & temporary altered state

Question 28

Define epilepsy

Answer 28

A group of syndromes characterized by unprovoked, recurrent seizures

Question 29

Define status epilepticus

Answer 29

Continuous seizure activity for more than 5 min or 2 or more sequential seizures that occur w/o full recovery of consciousness btwn attacks

Question 30

List 10 common causes of seizures

Answer 30

1) trauma 2) ETOH withdrawal 3) illicit drug use 4) brain tumor 5) congenital malformations 6) stroke 7) metabolic disorders 8) Alzheimer's disease 9) Neurodegenerative disease 10) idiopathic

Question 31

List 2 examples of metabolic disorders that can cause seizures

Answer 31

1) uremia 2) electrolyte imbalances

Question 32

List 4 things that can trigger seizures (**Hint: think environmental factors**)

Answer 32

1) flashing lights 2) stress 3) certain drugs 4) metabolic changes

Question 33

List 5 common causes of epilepsy

Answer 33

1) genetic causes 2) head trauma 3) medical disorders 4) prenatal injury 5) developmental disorders

Question 34

Epilepsy may occur in genes coding for what 3 different things

Answer 34

1) ion channels 2) neuronal receptors 3) transcription factors

Question 35

List 3 medical disorders that can cause epilepsy

Answer 35

1) dementia 2) meningitis 3) encephalitis

Question 36

List 2 developmental disorders that can cause epilepsy

Answer 36

1) autism 2) down syndrome

Question 37

Who can have a seizure?

Answer 37

ANYONE

Question 38

For an actual seizure to occur what 3 things have to be occurring?

Answer 38

1) excitable neurons 2) increase in glutaminergic activity 3) reduction in activity of normal inhibitory GABA projection

Question 39

Pathophysiology of seizures (**Hint: 3**)

Answer 39

1) messages from body are carried by neurons of the brain through discharges of electrochemical energy 2) impulses occur in bursts 3) during periods of unwanted discharges, parts of the body may act erratically

Question 40

What are the 2 classifications of seizures?

Answer 40

1) focal or partial 2) generalized

Question 41

List 2 types of focal/ partial seizures

Answer 41

1) simple partial 2) complex partial

Question 42

List 4 types of generalized seizures

Answer 42

1) Absence (Petit-mal) 2) Tonic-clonic (Grand mal) 3) Atonic/ akinetic (drop attacks) 4) status epilepticus

Question 43

Where do focal seizures occur in the brain?

Answer 43

Start & remain in **ONE** hemisphere

Question 44

Pathophysiology of focal seizures

Answer 44

High frequency bursts of action potentials & hypersynchronization

Question 45

What can happen to a patient's awareness when experiencing a focal seizure?

Answer 45

Awareness may be maintained or lost

Question 46

What is an aura? & what type of seizures can they be associated with?

Answer 46

Warning sensation before a seizure occurs - can occur with focal seizures

Question 47

Focal seizures may have ___, ___, ____ Sx, & ____

Answer 47

Motor, sensory, autonomic Sx, & automatisms

Question 48

Autonomic Sx of focal seizures

Answer 48

Due to stimulation of ANS (i.e. pallor, sweating, pupillary dilation, epigastric sensation)

Question 49

What are automatisms seen in focal seizures?

Answer 49

Coordinated involuntary movements occurring during state of impaired consciousness either during or after seizure -Patient is unaware; often associated w/ temporal lobe seizures

Question 50

Focal seizure when pt retains awareness is when? **Hint: 2**

Answer 50

1) Person is aware, & can experience body movements, like a jerk 2) May experience an aura

Question 51

Focal seizure with awareness is similar to what other type of seizure?

Answer 51

Partial seizures

Question 52

Focal seizure with altered/impaired consciousness is when?

Answer 52

Seizure may spread to the other hemisphere, causing loss of awareness

Question 53

Where do partial seizures usually begin?

Answer 53

In one hemisphere (typically temporal or frontal lobe)

Question 54

Partial seizures can be characterized as ___ or ___

Answer 54

simple or complex

Question 55

Pathophysiology of generalized seizures **Hint: 3**

Answer 55

1) starts in 1 hemisphere & spreads w/ involvement of both hemispheres 2) may have motor &/or nonmotor Sx 3) impairment of consciousness

Question 56

How are tonic-clonic (grand mal) seizures characterized?

Answer 56

Begin with rigid violent contractions (tonic) followed by repetitive (clonic) activity of all extremities **Body stiffness & relaxation**

Question 57

List 4 things seen in tonic-clonic seizures that help identify them

Answer 57

Muscle stiffness, dilation of pupils, altered respirations **usually lasts < 1 min**

Question 58

How are absence seizures characterized?

Answer 58

Short episodes of staring & loss of consciousness ~ 10 sec

Question 59

How are myoclonic seizures characterized?

Answer 59

B/L jerking of muscles w/ no loss of consciousness

Question 60

How are atonic seizures characterized?

Answer 60

Sudden loss of muscle tone; "drop to ground"

Question 61

Status epilepticus is identified by what 2 things?

Answer 61

1) continuous seizure activity for > 5 min 2) 2 or more sequential seizures that occur w/o full recovery of consciousness between attacks

Question 62

What seizure classification is considered a neurological emergency?

Answer 62

Status epilepticus

Question 63

Which type of seizure requires immediate intervention? & why?

Answer 63

Status epilepticus → b/c extreme energy expenditure & potential lack of O2 during prolonged seizures

Question 64

How do we Dx seizures? **Hint: 3**

Answer 64

1) H&P 2) neurological exam 3) diagnostic procedures (chemistries; toxicology screens; CT; MRI; EEG)

Question 65

What are the 3 phases of seizures?

Answer 65

1) Pre-ictal 2) Ictal 3) Post-ictal

Question 66

Define pre-ictal phase

Answer 66

May be started by a trigger &/or preceded by an aura

Question 67

Define ictal phases

Answer 67

**Actual seizure** Increases in metabolic demand

Question 68

Define post-ictal phase

Answer 68

**Post seizure** Has decreased responsiveness; feels fatigued