EEG- Graf

Question 1

EEG records the summation of

Answer 1

postsynaptic potentials

Question 2

Does normal EEG exclude seizures?

Answer 2

no, you need to do long term recordings over days because seizures could happen in between the normal recordings

Question 3

What is quantitative EEG?

Answer 3

• it is usually recorded over the entire scalp with 25 electrodes
• need a computer program to analyze the data

There is interference with electrical devices for the P lab (EEG)

Question 4

Patterns of neuronal electrical activity recorded are called what and expressed in what?

Answer 4

brain waves

Hertz

Question 5

What is the difference between alpha, beta, theta, and delta waves?

Answer 5

Alpha: at rest and awake; reflects synchronized activity of the brain with little or few outside influences; generated by pacemakers in the brain

Beta: because when you’re awake or meant to be alert; have a mixture of EPSPs and IPSPs; the higher the amplitude the lower the frequency

Theta: common in children but abnormal in adults

Delta: when you fall asleep; high amplitude

Question 6

Brain waves can change due to what?

Answer 6

change with age, sensory stimuli, brain disease, and the chemical state of the
body

Question 7

A flat EEG (no electrical activity) is clinical

evidence of

Answer 7

death

Question 8

What can produce artifacts in EEG recordings?

Answer 8

sneezing, blinking, etc.

Question 9

What is the alpha block?

Answer 9

• close your eyes
• elicits the beta waves although the eyes are closed

told Brian to calculate 17x35 and it produced the alpha block

Beta waves are considered normal and are the dominant rhythm in subjects whose eyes are open or are otherwise attentive to external stimuli or exerting specific mental effort. Beta rhythms also occur during rapid eye movement (REM) sleep. In this situation the typical alpha rhythm is suppressed and supplanted by beta waves

Question 10

Flashing lights can cause?

Answer 10

epileptic seizures

Question 11

Electrocerebral silence in a patient in deep coma following cardiac arrest. What does this mean?

Answer 11

the patient is dead if they are brain dead although there is still electrical activity in the heart

Question 12

What is the difference between the EEG recordings between an individual with bruxism and REM sleep?

Answer 12

Bruxism (gnashing of teeth during sleep):muscle activity

REM sleep (when your dreams come about): thick eye movements and no muscle activities; dreams are necessary for sanity and well being; suppression of dreams created hallucinations during daytime

Question 13

EEG is used to help diagnose the presence of

Answer 13

seizure, coma

Question 14

In a person attentive to an external stimulus or thinking hard about a task, the alpha rhythm is replaced by

Answer 14

Beta wave

Question 15

REM sleep is a sleep pattern that

Answer 15

resembles awake sleep

Question 16

Which of the following is a typical case for EEG diagnostics?

Answer 16

Temporal epilepsy

Question 17

Which of the following would you typically expect to see in a sleep EEG?

Answer 17

Alpha wave
Beta
Spindles
Sharp transitions

Question 18

EEG recordings are typically done with

Answer 18

25 surface electrodes on the scalp

Question 19

In order to localize precisely an ictal focus,

Answer 19

surface and intracranial electrode for several days

Question 20

A major disorder of the nervous system requiring EEG diagnosis?

Answer 20

Epilepsy

Question 21

EEG records which activity in the brain?

Answer 21

summation of postsynpatic potentials

Question 22

In a healthy, alert adult sitting with the eyes closed, the dominant EEG rhythm observed with electrodes over the occipital lobe is

Answer 22

Beta waves