N-Instrumentation 1,2

Front 1

Which of these is specified in dB/octave?

Back 1

Filter slope is specified in dB/octave.

Front 2

An impedance meter measures the quality of skin-electrode contact in

Back 2

An impedance meter measures the quality of skin-electrode contact in Kohms (thousands of ohms).

Front 3

Breathing pattern can influence EEG training. For example, when hyperventilation constricts cerebral blood vessels, it generates ______ activity.

Back 3

Fried has warned that hyperventilation can produce theta activity by constricting cerebral blood vessels.

Front 4

The standard electrode placement system draws an imaginary line from the nasion to the

Back 4

The International 10-20 system draws an imaginary line from the nasion to the inion.

Front 5

The majority of EEG power falls between

Back 5

The majority of EEG power (signal energy) falls between 0 and 20 Hz.

Front 6

The EEG primarily reflects graded _____ potentials in ______.

Back 6

The EEG primarily reflects graded excitatory and inhibitory postsynaptic potentials in cortical dendrites.

Front 7

Which bandpass can be used to measure theta EEG activity?

Back 7

Theta can be detected using a 4-7 Hz bandpass.

Front 8

Which bandpass can be used to measure alpha EEG activity?

Back 8

Alpha activity can be detected using an 8-12 Hz bandpass.

Front 9

In North America, contamination from line current occurs primarily at

Back 9

In North America, line current artifact produces the greatest contamination at 60 Hz. There may also be interference at 120 Hz and 180 Hz due to harmonics or multiples of 60-Hz artifact.

Front 10

If your voltage is 24 and resistance is 2, current is ______ amperes.

Back 10

Since voltage (E) = current (I) times resistance (R), if voltage is 24 and resistance is 2, current is 12 amperes.

Front 11

Which could worsen movement artifact in EEG recording?

Back 11

Lengthening a EEG electrode cable risks increasing movement artifact since this may make a standard cable a better antenna for electrical artifacts (e.g., 60-Hz noise).

Front 12

SMR activity can be detected from

Back 12

SMR activity can be detected from 12-15 Hz.

Front 13

Which of these is related to EEG signal frequency?

Back 13

Frequency is the number of cycles completed each second and is measured in Hz.

Front 14

Which EEG landmark is closest to the ear?

Back 14

The preauricular point (notch) is the depression at the base of the ears.

Front 15

EOG artifact in EEG recording is due to

Back 15

EOG artifact is produced by electrical potential differences between the aqueous and vitreous humors of the eye.

Front 16

The EEG signal is measured in microvolts. A microvolt is ______ of a volt.

Back 16

A microvolt is 1 millionth of a volt.

Front 17

Power refers to the square of signal

Back 17

Power means the square of signal amplitude or strength. EEG and EMG power are measured in microvolts squared or picowatts squared.

Front 18

Which of these biological signals is always below 5 Hz?

Back 18

Slow cortical potentials are below 5 Hz. Slow cortical potentials are shifts in electrical potential that are detected from the scalp. These potentials, including the contingent negative variation (CNV), readiness potential (RP), and P300 (P3 wave), reflect gradual changes in cortical dendrite polarization.

Front 19

______ artifact is usually the strongest source of contamination during EEG recording.

Back 19

Sixty-Hz (50-Hz) artifact is usually the most powerful source of EEG signal contamination.

Front 20

Which is a slow cortical potential?

Back 20

The P300 wave is one of the slow cortical potentials. Slow cortical potentials are shifts in electrical potential slower than 5 Hz that are detected from the scalp. These potentials, including the contingent negative variation (CNV), readiness potential (RP), and P300 (P3 wave), reflect gradual changes in cortical dendrite polarization.

Front 21

A 1-second exposure to currents above _____ mA can produce ventricular fibrillation.

Back 21

50

A 1-second exposure to currents above 50 mA can produce fatal ventricular fibrillation.

Front 22

The highest amplitude EEG frequency band is called the ______ frequency.

Back 22

The highest amplitude EEG frequency band is called the dominant frequency.

Front 23

What indexes an electroencephalograph's ability to detect the smallest change in EEG activity?

Back 23

Resolution is the specification that indexes an electroencephalograph's ability to detect the smallest change in EEG activity. Smaller resolution specifications are better.

Front 24

A dummy subject is used with EEG or EMG instruments to measure

Back 24

A dummy subject is a network of resistors that simulates typical skin-electrode impedance. This device is used to measure total environmental and instrument noise.

Front 25

Which common mode rejection ratio specification would you prefer in an electroencephalograph?

Back 25

A specification of 110 dB is best. Larger common mode rejection ratios are preferred because they mean that the biofeedback instrument controls artifact more effectively.

Front 26

What circuit does a blown fuse illustrate?

Back 26

A blown fuse illustrates an open circuit since heat melts the filament that completes the circuit path. This prevents electron movement.

Front 27

Which technique is used to quantify EEG amplitude within specific frequency bands?

Back 27

Fast Fourier Transformation (FFT) is used to quantify EEG amplitude within specific frequency bands.

Front 28

What forces electrons to move in a circuit?

Back 28

The electromotive force, which is produced by a difference in electrical potential, causes electrons to move in a circuit.

Front 29

Which filter selects signals below a specified cutoff frequency?

Back 29

A low-pass filter selects signals below a cutoff frequency.

Front 30

Opposition to the movement of an AC signal through a circuit is called

Back 30

Opposition to the movement of an AC signal through a circuit is called impedance. We measure impedance to determine the quality of skin-electrode contact.

Front 31

Which filter selects signals above a specified cutoff frequency?

Back 31

A high-pass filter selects signals above a specified cutoff frequency.

Front 32

If signal amplitude is 1 microvolt at midband, the amplitude at the corner frequencies is ______ microvolt.

Back 32

By definition, signal amplitude at a corner frequency is .707 of the amplitude at the midband frequency.

Front 33

what measures an electroencephalograph's ability to detect the smallest signal voltage?

Back 33

The sensitivity specification measures an electroencephalograph's ability to detect the smallest signal voltage. Lower sensitivity specifications are better.

Front 34

what is measured in microvolts?

Back 34

Signal strength or amplitude is measured in microvolts.

Front 35

Which is typically the strongest source of interference in SEMG recording?

Back 35

Sixty-Hz artifact is typically the strongest source of interference in EEG recording.

Front 36

When there is a break in an electrode cable, impedance measured from both ends of the cable should be _____ ohms.

Back 36

A broken electrode cable has infinite impedance because electrons cannot move across a break in the cable.

Front 37

EEG signals are changed into ______ during optical isolation.

Back 37

EEG signals are changed into light during optical isolation to protect the patient from shock.

Front 38

A notch filter to remove line current noise typically operates from _______ in North America.

Back 38

A notch filter to remove line current noise typically operates from 58-62 Hz in North America.

Front 39

What expresses a ratio of 10,000 to 1?

Back 39

80 dB expresses a ratio of 10,000 to 1. Divide the logarithmic expression by 20 to find the number of 0s. Example: 80 dB/20 = 4. This means that the ratio is 10,000:1.

Front 40

What integration method produces the highest EEG and EMG values?

Back 40

The peak-to-peak integration method produces the highest EEG and EMG values. Peak-to-peak amplitude is two times peak amplitude.