Patterns: Normal Variants

Question 1

8-13 Hz
20-60 uV

Answer 1

Alpha

Question 2

What is the morphology of alpha?

Answer 2

-sinusoidal
-waxing and waning

Question 3

When do you see alpha? Where?

Answer 3

• eyes closed, relaxed, awake
• posterior dominant

Question 4

What is the reactivity of alpha?

Answer 4

• attenuates with visual stimulus
• mental alerting

Question 5

alpha attenuation in only one hemisphere

Answer 5

Bancaud’s Phenomenon

Question 6

what age is alpha usually present by?

Answer 6

by age 3

Question 7

alpha is related to what?

Answer 7

cerebral blood flow

Question 8

frequency half of the alpha rhythm

Answer 8

slow or sub-harmonic

Question 9

double the alpha frequency

Answer 9

fast or harmonic

Question 10

decrease in amplitude

Answer 10

attenuation

Question 11

alpha is the main activity that could be seen in a patient who suffers anoxia

Answer 11

alpha coma

Question 12

delta intermixed with alpha

Answer 12

PSWY

Question 13

what age is PSWY seen?

Answer 13

6-12 years old, rare before 2 and after 25

Question 14

what is the reactivity of PSWY?

Answer 14

• attenuates with eye opening
• disappears in sleep

Question 15

what enlarges PSWY?

Answer 15

HV

Question 16

> 13 Hz
5-20 uV

Answer 16

Beta

Question 17

beta is found where?

Answer 17

frontal-central

Question 18

PSWY is seen where?

Answer 18

occipitals

Question 19

7-11 Hz
20-50 uV
arch or comb shaped

Answer 19

Mu Rhythm

Question 20

what is the reactivity of Mu?

Answer 20

blocked by contralateral thumb movement

Question 21

where is Mu seen?

Answer 21

centrals

Question 22

4-7 Hz

Answer 22

Theta

Question 23

when is theta seen?

Answer 23

during drowsiness or sleep

Question 24

5-7 Hz
2-10 secs

Answer 24

RMTD

Question 25

where is RMTD seen?

Answer 25

mid temporals

Question 26

when is RMTD seen?

Answer 26

drowsiness

Question 27

How to determine RMTD from epileptiform activity?

Answer 27

• RMTD is brief in duration
• Absence of evolution in frequency, distribution, and waveform
• RMTD begins in the same form it ends
• RMTD is monomorphic

Question 28

trains of 14 or 6 per second
comb-like shape

Answer 28

14 & 6 Positive Bursts

Question 29

where are 14 & 6 Positive Bursts seen?

Answer 29

posterior temporals
best seen in referential montage

Question 30

What state is 14 & 6 Positive Bursts seen?

Answer 30

drowsiness and light sleep

Question 31

What age groups is 14 & 6 Positive Bursts seen?

Answer 31

14-16, not usually after 25

Question 32

less than 20-30 uV
bi/triphasic

Answer 32

Lambda

Question 33

Where is lambda seen?

Answer 33

occipitals

Question 34

What state is Lambda seen?

Answer 34

eyes opened, scanning

Question 35

when is lambda developed?

Answer 35

after 1

Question 36

5-7 Hz
low voltage
rhythmic bursts lasting 1-2 sec

Answer 36

6 Hz spike and wave discharges (phantom spikes)

Question 37

where are phantom spikes seen?

Answer 37

parietal, occipitals

Question 38

what state is phantom spikes seen?

Answer 38

awake, drowsy, light sleep

Question 39

what are the acronyms for phantom spikes?

Answer 39

• FOLD (female, occipital, low amp, drowsiness)
  -WHAM (wake, high amp, anterior, male)

Question 40

18-35 Hz
mu like
high amp
seen over burr holes

Answer 40

breach rhythm

Question 41

50 uV
fast spike without associated slow wave

Answer 41

BETS

Question 42

where can BETS be seen?

Answer 42

temporals

Question 43

what state is BETS seen in?

Answer 43

drowsiness, light sleep

Question 44

what age is BETS seen?

Answer 44

adulthood pattern (30-60)

Question 45

sharp waves, slow waves
20 seconds- minutes

Answer 45

SREDA

Question 46

• abrupt, repetitive monomorphic sharp discharges
• gradual with few sharp discharges followed by rhythmic slow

Answer 46

SREDA

Question 47

what age is SREDA usually seen?

Answer 47

60 or older

Question 48

when can SREDA be seen?

Answer 48

during or after HV