Normal Adult EEG

Reading about sleep always knocks me out

Are there ever periods of 0 activity in any channel?

No

What is the Posterior Dominant Rhythm (PDR)?

Posterior Activity has increased amplitude and decreased frequency when the eyes are closed, but the patient is awake

What happens to Posterior activity when an awake patient opens their eyes

It attenuates

What is the Anterior-Posterior gradient

Lower amplitude/higher frequency occurs anteriorly and switches to higher amplitude/lower frequency posteriorly

When can healthy normal Delta activity be observed?

Never

Does healthy Posterior Dominant Rhythm always have symmetrical amplitude?

No, right hemisphere amplitude can be a little higher

Does healthy Posterior Dominant Rhythm always have symmetrical Frequency?

Yes, asymmetrical frequency in PDR is abnormal

What wave frequency can by enhanced by Sedative, hypnotic, or anxiolytic drugs?

Beta

A healthy increase in Theta waves is a sign of what?

Drowsiness

What’s the duration of a Spike wave?

20-70 ms

What’s the duration of a Sharp Wave

70-200 ms

What’s a Polyspike Complex?

A short series of spike waves, especially in a focal area

What is causing these slow phase reversals?

Slow eye movement

What stage of sleep do these waveforms indicate?

Stage I, drowsiness`

What happens to Posterior Dominant Rhythm in Stage I of sleep?

It attenuates

Sharp Waves centered around Cz during sleep are called what?

Vertex Waves

What is a healthy Vertex Wave charge?

Negative

What stages of sleep can have healthy Vertex Waves?

Stage I and Stage II

What is this sleeping waveform pattern called?

Sleep Spindles

What stage of sleep has Sleep Spindles?

Stage II

What is this sleeping waveform pattern called?

K Complex

In what stages of sleep can we see K Complexes?

Stage II and Stage III

What is the dominant wave frequency of Stage II sleep?

Theta

What is the dominant frequency of Stage III sleep?

Delta

What does REM stand for?

Rapid Eye Movement

Does frequency increase or decrease in REM sleep?

Increase

What is the healthy central episodes of sharp wave activity found in REM sleep called?

Sawtooth Waves

How long is a normal sleep cycle?

Around 90 minutes

Is it normal to observe REM sleep during a routine EEG?

No