WorksheetsREVISION III
Total questions: 15
Worksheet time: 8mins
Which of the following best describes a sine wave in EEG analysis?
A sharp and broken line
A wave that only appears during sleep
A random pattern that does not repeat
A smooth, continuous wave that repeats in time
When performing an EEG for ECI determination, why is it important to confirm amplifier sensitivity settings?
To reduce the chance of detecting cardiac artifact
To amplify muscle artifacts for better differentiation
To ensure the EEG machine doesn't overheat during prolonged recordings
To make sure any residual cerebral activity of low amplitude can be detected
What is the purpose of adjusting the sampling rate in long-term EEG monitoring?
To reduce the amount of data recorded
To improve the resolution of EEG waveforms
To synchronize the video recording with EEG data
To prevent electrode noise from appearing in the data
What is the recommended high-pass filter setting for long-term EEG to preserve low-frequency brain activity?
5 Hz to enhance spike detection
2 Hz to reduce sweating artifacts
0.5 Hz to avoid losing slow waveforms
10 Hz for better phase reversal visibility
What does a bipolar montage measure?
The signal from a single electrode to a distant reference point
The average signal from multiple electrodes across the entire scalp
The difference between electrodes placed over the same cortical region
The electrical potential difference between two adjacent electrodes
What does "burst suppression" indicate in an EEG?
High-amplitude waves interspersed with flat periods
A pattern of rapid, rhythmic spikes seen during seizure activity
A state of reduced brain wave activity seen during slow-wave sleep
A normal transition phase between sleep stages with rhythmic waves
What role does the brainstem play in EEG wave generation?
The brainstem controls the rhythmic generation of delta waves during deep sleep
The brainstem primarily generates high-frequency beta waves seen during intense mental activity
The brainstem has no involvement in EEG wave generation, as its role is limited to basic life functions
The brainstem generates theta waves and directly modulates the alpha rhythms in the cortex during periods of relaxation
How do brainstem nuclei influence EEG during sleep-wake transitions?
They modulate thalamocortical circuits to shift EEG frequencies
Brainstem nuclei control peripheral motor responses unrelated to EEG signals
Brainstem nuclei only affect autonomic functions, not cortical EEG rhythms
Brainstem nuclei synchronize cerebellar output to regulate REM and NREM states
A routine EEG shows high-voltage sharp waves over the centrotemporal region during sleep in a child with no cognitive impairment. What does this most likely indicate?
Benign epilepsy with centrotemporal spikes
Infantile spasms with hypsarrhythmic background
Focal cortical dysplasia causing epileptic encephalopathy
Juvenile myoclonic epilepsy with secondary generalization
A patient with a history of generalized tonic-clonic seizures presents for EEG. The report notes generalized 3 Hz spike-and-wave activity with a slow background. What is the most likely diagnosis?
Lennox-Gastaut syndrome
Juvenile myoclonic epilepsy
Childhood absence epilepsy
Focal onset seizures with secondary generalization
What is a limitation of Video Telemetry Recording (VTR) in diagnosing non-epileptic seizures?
EEG recordings are usually too brief to capture complex seizure events during video monitoring
Video data can only be used for identifying focal seizures, limiting its utility for generalized seizure types
Video alone cannot identify seizure activity without corresponding EEG patterns, which are essential for accurate diagnosis
The video often provides an overemphasis on motor movements, making it difficult to differentiate between epileptic and non-epileptic events
In Amyotrophic lateral sclerosis (ALS), what Electromyogram (EMG) finding in the first dorsal interosseous (FDI) muscle is most indicative of lower motor neuron degeneration?
Fibrillation potentials and fasciculations at rest
Decreased recruitment without evidence of denervation
Normal insertional activity with mildly reduced amplitude
Prolonged sensory nerve latency with preserved motor conduction
Which nerve is best assessed during a sensory nerve conduction study?
Median nerve sensory branch recorded from the thumb
Tibial nerve recorded from the plantar surface of the foot
Sural nerve in the lower limb using antidromic stimulation
Ulnar nerve using orthodromic stimulation to the fifth digit
In optic neuropathy due to demyelination, which VEP finding is most commonly observed?
Decreased P100 latency and increased amplitude, indicating cortical hyperactivity
Increased N75 latency with no change in P100 amplitude, indicating early cortical changes
Abnormal P100 waveform with absence of cortical responses, suggesting significant optic nerve degeneration
Prolonged P100 latency with reduced amplitude, reflecting slowed transmission in the demyelinated optic pathways
In a healthy individual with normal cerebral blood flow, which TCD finding would be expected in the middle cerebral artery (MCA)?
Normal flow velocity (50-100 cm/s), low PI
Flow velocity of 200 cm/s with a pulsatility index of 0.2
High flow velocity with a pulsatility index of 1.5 or higher
Low flow velocity and elevated PI, indicating poor perfusion
