Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ABRET Prep 2/2 > II-D. Digital instrumentation > Flashcards

II-D. Digital instrumentation Flashcards

1
Q

Which of the following converts an analog signal into a series of digital binary numbers?
A) Fast Fourier Transform
B) Impedance Meter
C) Differential Amplifier
D) A/D Converter

A

A/D Converter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens when a 60 cycle sine wave is sampled at 100 hertz?
A) digital filtering
B) subharmonic responce
C) aliasing
D) overlap of data

A

aliasing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Clipping of the waveforms occurs when:
A) the sensitivity is set too low, i.e. 20 uV/mm
B) the signal is aliased
C) the sampling rate is too fast
D) the signal is outside the range of the digitizer

A

the signal is outside the range of the digitizer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which of the following settings is most sensitive?
A) 2 mV/cm
B) 5 uV/mm
C) 2 uV/mm
D) 5 mV/cm

A

2 uV/mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The waveforms contain frequencies as high as 100 hertz. What is the Nyquist sampling rate?
A) 50 samples/second
B) 25 samples/second
C) >200 samples/second
D) >100 samples/second

A

> 200 samples/second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

VOLTAGE RESOLUTION
A) horizontal sampling rate
B) frequency resolution
C) Analog-to-digital converter
D) bandwidth

A

Analog-to-digital converter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which of the following instrumentation setting change may result in the elimination of cortical spikes?
A) Change the LFF from 1 Hz to 0.1 Hz
B) Change the HFF from 70 Hz to 100 Hz
C) Change the LFF from 1 Hz to 5 Hz
D) Change the HFF from 70 Hz To 15 Hz

A

Change the HFF from 70 Hz To 15 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which of the following instruments magnifies the common-mode voltage difference between two inputs?
A) A/D Converter
B) Differential Amplifier
C) Fast Fourier Transform
D) Impedance Meter

A

Differential Amplifier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

EEG amplifiers work on the principle(s) of
A) differential discrimination
B) differentiation and amplification
C) aliasing
D) amplification

A

differentiation and amplification.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The sharpness of the frequency response curve is determined by the filter
A) rolloff
B) capacitance
C) bandwidth
D) notch

A

rolloff.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which of the following is the most appropriate sampling rate that should be used for a HFF setting of 70 Hz, according to ACNS 2016 Guidelines?
A) 210 samples per second
B) 140 samples per second
C) 30 samples per second
D) 256 samples per second

A

256 samples per second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

With high frequency filtering, muscle artifact may become distorted and look like
A) lambda activity
B) theta activity
C) beta acitivity
D) alpha

A

beta activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A 0.5 Hz wave is enhanced without affecting a spike by using
A) LF 0.3 Hz
B) LF 1 Hz
C) HF 35 Hz
D) LF 5 Hz

A

LF 0.3 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

According to the Guidelines, how many bits of resolution is required?
A) 10
B) 8
C) 16
D) 13

A

16

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which of the following is not useful in digital EEG recordings?
A) balance of electrode impedances
B) bio calibration
C) filters
D) system reference

A

bio calibration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

All of the following factors favor cancellation or signals in the two inputs or an amplifier, except
A) shorter inter-electrode distance
B) cerebral potentials in common mode
C) equal impedances in the inputs
D) unequal impedances in the inputs

A

unequal impedances in the inputs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

LONG TIME CONSTANT
A) HFF of 35 Hz
B) LFF of 0.1 Hz
C) HFF of 70 Hz
D) LFF of 1 Hz

A

LLF of 0.1 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A time constant of 0.5 sec:
A) Low Filter 5.0 Hz
B) High Filter 35 Hz
C) Low Pass Filter 15 Hz
D) High Pass Filter 0.3 Hz

A

High Pass Filter 0.3 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

High data sampling rates in a digital EEG machine create
A) long EEG recordings
B) choppy, rigid lines
C) smooth, connected lines
D) low amplitude EEG activity

A

smooth, connected lines.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

For low frequency filters (LFFs), the corresponding time constants for LFF cutoff frequency of 3 Hz would be
A) 0.03 sec
B) 0.016 sec
C) 0.06 sec
D) 0.05 sec

A

0.05 sec

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Digital EEG montages are reformatted by using
A) system reference
B) the Nyquist theorem
C) referentially recorded data
D) Fourier analysis

A

system reference.

22
Q

Which of the following sites is most commonly used for the ground electrode in EEG?
A) Oz
B) Pz
C) Fpz
D) Fz

A

Fpz

23
Q

Low sampling rate may cause fast frequencies to appear slower:
A) overfiltering
B) long time constant
C) aliasing
D) low impact impedance

A

aliasing

24
Q

Term used to describe the way a signal is sampled at intervals and assigned a numeric value:
A) Linear filtering
B) Aliasing
C) Sampling skew
D) Sampling Rate

A

Sampling Rate

25
Q

Which of the following time constants would best display delta activity?
A) 0.1 second
B) 1.0 second
C) 0.3 second
D) 0.5 second

A

1.0 second

26
Q

In a differential amplifier, if input 1 received a voltage of + 50 microvolts and input 2 a voltage of - 100 microvolts, the output voltage and deflection would be approximately
A) 150 upward
B) 50 downward
C) 150 downward
D) 50 upward

A

150 downward

27
Q

Input impedance should be
A) equal to the common mode rejection ratio
B) less than common mode rejection ratio
C) very high
D) very low

A

very high

28
Q

Doubling the inter-electrode distances will have what effect on the waveforms?
A) Decrease muscle artifact
B) Increase slow activity
C) Increase amplitude
D) No effect

A

Increased amplitude

29
Q

UNDERSAMPLING
A) Impedance
B) Common Mode Rejection
C) Aliasing
D) Fast Fourier transform

A

Aliasing

30
Q

2016 ACNS guidelines recommends a CMRR of at least:
A) 90 dB
B) 70 Hz
C) 90 Hz
D) 70 dB

A

90 dB

31
Q

Increasing the number of seconds displayed on the monitor
A) increases spike amplitude
B) decreases spike duration
C) increases spike duration
D) does not change spike amplitude or duration

A

does not change spike amplitude or duration

32
Q

Which of the following principles best applies to the EEG amplifiers?
A) Filtering
B) Sampling
C) Aliasing
D) Common mode rejection

A

Common mode rejection

33
Q

What is the specification of the minimum sampling rate used, in relation to the highest frequency signal recorded?
A) Nyquist theory
B) Ohm’s theory
C) Coulombs law
D) Paley-Winer therorem

A

Nyquist theory

34
Q

What percentage of actual amplitude will be visible of 15 Hz. wave when using a HFF setting of 15 Hz.?
A) 0.15
B) 0.3
C) 0.7
D) 0.5

A

0.7

35
Q

The amount by which the differential amplifier increases the magnitude of the input signal is its
A) resistance
B) filter
C) input impedance
D) sensitivity

A

sensitivity

36
Q

VERTICAL RESOLUTION
A) Frequencies
B) Bits
C) Amplitude
D) Duration

A

Amplitude

37
Q

The 60 Hz notch filter will have the greatest effect on a waveform having a duration of
A) 25 msec
B) 16 msec
C) 50 msec
D) 10msec

A

16 msec

38
Q

Which of the following most closely relates to the ratio of an amplifiers output to input signal?
A) System Gain
B) Display sensitivity
C) CMRR
D) Impedance

A

System Gain

39
Q

A 0.3 Hz wave would be attenuated by what percentage with a 0.3 Hz filter?
A) 0.7
B) 0.3
C) Unaffected
D) 0.5

A

0.3

40
Q

A device that alters the amplitude of specific frequencies of a signal:
A) capacitor
B) transducer
C) filter
D) conductor

A

filter

41
Q

FREQUENCY RESPONSE CURVE
A) Input impedance
B) Filters
C) Sensitivity
D) Duration

A

Filters

42
Q

FREQUENCY
A) influenced by CMRR and measured in microvolts
B) influenced by sensitivity and measured in cycles per second
C) influenced by sampling rate and measured in hertz
D) influenced by impedance and measured in millimeters

A

influenced by sampling rate and measured in hertz

43
Q

If the Low Frequency Filter is changed from 1 Hz to 5 Hz, how will a 2 Hz slow wave be affected?
A) It will be significantly attenuated
B) It will not be affected
C) It will be minimally (insignificantly attenuated
D) It will be accentuated

A

It will be significantly attenuated

44
Q

Gradual changes in amplitude, frequency, or spatial distribution of rhythms is known as:
A) Evolution
B) Background activity
C) Attenuation
D) Asymmetry

A

Evolution

45
Q

The ability of an amplifier to reject like signals.
A) amplifier gain
B) phase reversal
C) sensitivity
D) common mode rejection

A

common mode rejection

46
Q

TIME CONSTANT
A) Low frequency filter
B) Sensitivity
C) Gain
D) Time axis

A

Low frequency filter

47
Q

Which mathematically converts the time function into a sine wave of different frequencies?
A) Differential Amplifier
B) Impedance Meter
C) A/D converter
D) Fast Fourier Transform

A

Fast Fourier Transform

48
Q

Signals common to both inputs of a differential amplifier with like frequency, amplitude and phase are:
A) canceled
B) attenuated 37%
C) amplified
D) attenuated 63%

A

canceled

49
Q

2016 ACNS Guidelines recommends a minimum horizontal resolution of:
A) 16 Hz
B) 8 bits
C) 16 bits
D) 8 Hz

A

16 bits

50
Q

A LFF setting of 5 Hz. will attenuate a 5 Hz. wave by approximately:
A) 30 mm
B) 0.05
C) 5 mm
D) 0.3

A

0.3

51
Q

For a high frequency filter setting of 70 Hz, the Nyquist frequency is?
A) 210 samples per sec
B) 140 samples per sec
C) 10 samples per sec
D) 20 samples per sec

A

140 samples per sec

52
Q

COMMON MODE REJECTION
A) Half cycle amplifier
B) Differential amplifier
C) Referential amplifier
D) Bipolar amplifier

A

Differential amplifier

ABRET Prep 2/2 (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions