Mod A Flashcards
What does EEG primarily measure?
a) Action potentials of individual neurons
b) Summation of electrical potentials in the extracellular fluid of postsynaptic neurons
c) Magnetic fields generated by neurons
d) Blood flow in the brain
b) Summation of electrical potentials in the extracellular fluid of postsynaptic neurons
To create a measurable EEG signal, neurons must be:
a) Arranged randomly
b) Arranged in a parallel fashion (perpendicular to the cortex) and synchronously active
c) Aligned parallel to the cortex
d) Randomly aligned
b) Arranged in a parallel fashion (perpendicular to the cortex) and synchronously active
What is volume conduction in the context of EEG?
a) The transmission of sound waves in the brain
b) The process by which a pool of ions attracts nearby ions of the opposite charge, resulting in a wave of charge
c) The propagation of EEG signals within the brain through extracellular space
d) The conduction of electrical signals through individual neurons
c) The propagation of EEG signals within the brain through extracellular space
Why is electrode gel necessary in EEG recording?
a) To improve skin conductivity
b) To reduce impedance
c) To create a conductive path from the scalp to the electrode
d) All of the above
d) All of the above
What is the International 10/20 System used for in EEG electrode placement?
a) To identify 10 important EEG bands
b) To determine electrode impedance
c) To guide the placement of electrodes based on anatomical landmarks
d) To calibrate EEG amplification
c) To guide the placement of electrodes based on anatomical landmarks
What is the main purpose of an amplifier in an EEG system?
a) To maximize the Signal to Noise Ratio (SNR)
b) To increase the size of the noise
c) To reduce the amplitude of EEG signals
d) To amplify only negative voltage
a) To maximize the Signal to Noise Ratio (SNR)
Which EEG band is associated with relaxed wake state and lack of active cognitive processing?
a) Gamma
b) Alpha
c) Beta
d) Theta
b) Alpha
ERPs (Event-related potentials) are:
a) Continuous and spontaneous electrical activities
b) Small voltage fluctuations in the EEG time-locked to external or internal events
c) Large-amplitude oscillations in the brain
d) Long-duration electrical signals
b) Small voltage fluctuations in the EEG time-locked to external or internal events
What does the P300 component of ERPs primarily reflect?
a) Visual processing of faces
b) Motor preparation and execution
c) Allocation of attentional resources and working memory updating
d) Semantic processing
c) Allocation of attentional resources and working memory updating
What is the main advantage of EEGLab?
a) Excellent spatial resolution
b) Real-time source reconstruction
c) Free, works on Matlab, and analyzes data from different software
d) High-quality statistical analysis
c) Free, works on Matlab, and analyzes data from different software
What is the primary disadvantage of fMRI (Functional Magnetic Resonance Imaging) compared to EEG?
a) Limited temporal resolution
b) Excellent spatial resolution
c) Direct measurement of neuronal electrical activity
d) Low cost
a) Limited temporal resolution
Which of the following is an exogenous ERP component?
a) N170
b) P300
c) MMN (Mismatch Negativity)
d) N2c
c) MMN (Mismatch Negativity)
What is the primary function of the P600 ERP component?
a) Semantic processing
b) Syntactic violation in language processes
c) Allocation of attentional resources
d) Motor preparation and execution
c) Allocation of attentional resources
The readiness potential (RP or BP) is associated with:
a) Slow cortical negativity before the execution of voluntary movement
b) Sensory processing of visual stimuli
c) Auditory perception of discrepancies
d) Semantic integration of words in a sentence context
a) Slow cortical negativity before the execution of voluntary movement
What does CNV (Contingent Negative Variation) reflect in EEG?
a) Semantic processing of words
b) Sensory processing of visual stimuli
c) Expectancy, anticipatory attention, and motor preparation
d) Allocation of spatial attention
c) Expectancy, anticipatory attention, and motor preparation
In EEG, what is the role of ICA (Independent Component Analysis)?
a) Amplifying the EEG signal
b) Removing artifacts based on component maps
c) Measuring impedance of electrodes
d) Stimulating neural activity
b) Removing artifacts based on component maps
What is the primary purpose of averaging in ERP analysis?
a) To increase the size of noise in the signal
b) To reduce the Signal to Noise Ratio (SNR)
c) To enhance the amplitude of ERPs by summing random voltage
d) To reduce noise by aligning time-locked ERP activity across trials
d) To reduce noise by aligning time-locked ERP activity across trials
Why is electrode gel applied during EEG recording?
a) To improve skin conductivity and reduce impedance
b) To create a non-conductive barrier between the electrode and the skin
c) To minimize the saturation of space beneath the electrode
d) To amplify the EEG signals at the source
a) To improve skin conductivity and reduce impedance
What is the typical frequency range of the Gamma EEG band?
a) 0.5-3 Hz
b) 4-7 Hz
c) 8-13 Hz
d) 30-80 Hz
d) 30-80 Hz
How is SNR (Signal-to-Noise Ratio) measured in EEG?
a) By comparing the amplitude of the EEG signal to the frequency
b) By calculating the ratio of signal amplitude to noise amplitude
c) By measuring the impedance of electrodes
d) By counting the number of EEG channels
b) By calculating the ratio of signal amplitude to noise amplitude