REVISION II

Why is averaging used when analysing repeated EEG signals?

• To increase the size of the signal

• To make the signals more complex

• To combine different patients’ data into one graph

• To reduce random noise and highlight consistent brain responses

Which of the following filter settings is not acceptable when performing EEG for ECI assessment?

• Sensitivity at 2 µV/mm

• Low-frequency filter at 1 Hz

• High-frequency filter at 30 Hz

• High-frequency filter at 70 Hz

What should be done if an artifact is detected during Video Telemetry Recording (VTR)?

• Replace electrodes without any further analysis

• Reanalyze the data after removing all artifacts manually

• Immediately stop the recording and reset the equipment

• Identify and isolate the source of the artifact for later correctio

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

Which of the following describes the function of a referential montage in EEG?

• It compares the potential difference between adjacent electrodes

• It focuses on regional brain activity by isolating signals from different lobes

• It uses a common reference electrode to evaluate brain activity across regions

• It minimizes the effect of muscle artifacts by recording from all scalp regions simultaneously

What does "interictal" refer to in EEG terminology?

• A normal brain pattern with no signs of seizure activity present

• The time immediately after a seizure, when brain activity returns to baseline

• The period between seizures, when abnormal brain activity may still be present

• The initial onset phase of a seizure event, marked by a rapid increase in electrical activity

What is the role of the thalamus in generating EEG waves?

• The thalamus regulates the generation of alpha waves during sleep and wake cycles

• The thalamus directly produces delta waves by firing spontaneously without cortical interaction

• The thalamus has minimal involvement in EEG wave generation, as it only transmits sensory information

• The thalamus filters cortical signals, allowing high-frequency beta waves to be generated in the frontal cortex

What is the role of the ascending reticular activating system (ARAS) in EEG activity?

• It suppresses cortical activity to generate alpha rhythms during rest

• It activates the cerebral cortex to maintain wakefulness and alert EEG patterns

• It produces delta waves by inhibiting thalamic relay neurons during deep sleep

• It filters out sensory input during sleep, resulting in decreased cortical responsiveness

An EEG shows rhythmic 4–7 Hz theta activity localized to the temporal region in a drowsy adult. What is the most likely classification?

• Normal finding during drowsiness in temporal leads

• Diagnostic of non-convulsive status epilepticus in a wakeful adult

• Indicative of generalized epilepsy with secondary bilateral synchrony

• Suggestive of diffuse cortical dysfunction with frontal predominance

A 30-year-old patient presents with a history of focal seizures. The EEG shows intermittent sharp waves localized to the right temporal lobe. What does this EEG finding most likely suggest?

• Normal finding in a seizure-free patient

• Focal cortical dysplasia in the right temporal lobe

• Generalized tonic-clonic seizures with focal onset

• Non-epileptic seizures with no underlying brain abnormalities