5 thru 8 Flashcards
The purpose of electrode paste is to make a good connection between scalp and electrode so that:
A) electrons flow easily
B) resistance is low
C) the electrode stays in place
D) all of the above
Amplifiers, which are sensitive to microvolts, tend to pick up other signals, such as muscle artifact, which is often in the millivolt range and therefore:
stronger
A device known as a ______ amplifier is used to reject unwanted signals.
differential
The difference in EEG electrical potential measured between the ground and the other leads is measured in units known as:
microvolts
The resistance to the flow of electrons is usually measured in:
ohms
The term that refers to the actual energy available in an electrical current is:
power
Power is measured in:
watts
Current that flows continuously in one direction is known as:
direct current
The kind of current found in a common household outlet is known as:
alternating current
The basic equation for calculating power is:
voltage squared divided by resistance
EEG is a form of _____ because it has a positive and a negative phase.
alternating current
Two wave forms which shift from positive to negative at exactly the same rate are said to be:
in phase
Most equipment today measures voltage in _______ format.
peak to peak
Peak to peak measures voltage from the _____ of the voltage cycle.
positive peak to the negative peak
A device known as a _____ amplifier is used to reject unwanted signals.
differential
A particular method of placing electrodes on the scalp is referred to as a:
montage.
A montage where the ground is placed on one ear and the active and reference leads are placed at different locations on the scalp is referred to as a
A) bipolar montage
C) serial montage ****D) both A and C****
When using two EEG amplifiers, one usually hooks up the reference and active lead of each amplifier to the __________ of the cortex.
same side
According to Nunez there is an apparently ________ circle of error around 10-20 sites with respect to anatomical locations beneath the scalp.
3 centimeters
If individuals are not sufficiently relaxed, they may generate _____ in the EEG.
excessive beta
There is approximately a _____ variance, on average, between any given point on the 10-20 system and the area of the brain beneath it.
10%
The most common source of artifact in EEG is:
A) clenching the jaw
B) eye movement
C) swallowing
D) all of the above
Sixty-cycle hum can be reduced by making sure:
all outlets are properly grounded.
A montage involving an active lead on the scalp, a referential lead on one ear, and a ground lead on another ear is referred to as a:
monopolar montage
Periodic large amplitude spikes in theta may be due to:
eyeblinks
The best place for the ground electrode is:
any place on the head or back of the neck
The frequencies most associated with alpha are?
8-12
The frequencies most associated with beta are?
15-30
The frequencies most associated with delta are?
1-4
The frequencies most associated with gamma are?
35-45
A 14 Hz rhythm that indicates thalamic gating and which occurs over the sensory motor strip is known as?
SMR
Alpha is associated with attentional shifts and is considered ____________ for the brain.
a resting frequency
Alpha desynchronizes into beta waves during ________ ?
cognitive processing
__________ is the dominant frequency during sleep?
delta
40 Hz rhythms associated with learning become known as _______ rhythms?
Sheer
The brain requires greater amounts of energy and higher metabolism to generate ________ frequency waves.
higher
When the brain is learning a new task it is more active and generates more _______.
beta
When EEG spindles in the 11-15 Hz range begin to appear consistently in client’s EEG during training, then it is likely that you are seeing _____________ .
sleep spindles
