Welcome to your Neurophysiology Name Email 1. [While performing single-fiber EMG (SFEMG), which of the following measures should be undertaken?] Lower the high-frequency filter to 200 Hz Raise the high-frequency filter to 500 Hz Raise the low-frequency filter to 200 Hz Raise the low-frequency filter to 500 Hz None . 2. [Which of the following statements regarding analog-to-digital conversion is true?] Analog EEG measures the data at discrete time points Digital EEG is made up of continuous nondiscrete data The higher the sampling rate, the closer the digital signal resembles the analog signal The less number of bits an analog-to-digital converter (ADC) has, the more the digital sample resembles the analog signal None . 3. [Abductor pollicis brevis is innervated by the median nerve. The motor fibers for this innervation come from which of the following cervical roots?] C6, C7, C8 C7, C8 C5, C6, C7 C8, T1 None . 4. [A demyelinating lesion in the pons is likely to show] Prolonged N9 absolute latency Prolonged N9–P14 interpeak latency (IPL) Prolonged P14 absolute latency Prolonged P14–N20 IPL None . 5. [Myogenic motor evoked potentials (mMEPs; M-waves) obtained by transcranial electrical stimulation (TES) during intraoperative monitoring (IOM) are] Caused by compound muscle action potentials within the muscle Recorded only by needle electrodes Resistant to anesthetic effects Resistant to neuromuscular blockade None . 6. [Central conduction time (CCT) can be estimated by all of the following measurements except] P14–N20 interpeak interval (IPI) N13–N20 IPI N22–P31 IPI P31–P37 IPI None . 7. [A tumor in the medulla can be expected to reduce or abolish all of the following waveforms except] N13 P14 N18 P31 None . 8. [The following figure shows serial brainstem auditory evoked potentials (BAEPs) from apatient undergoing microvascular decompression of the trigeminal nerve. The bottomtrace is the earliest (11:51 a.m.) and the top trace is the latest (13:30 p.m.). All of the following statements are true based on the observed changes in BAEPs except (fig)] Wave I is absent after 12:21 p.m. Changes at 13:30 p.m. are consistent with cochlear infarction Changes after 12:23 p.m. are consistent with increase in sevoflurane dose Changes in Wave V until 12:05 p.m. are consistent with cerebellar traction None Comment . 9. [Decreased limb temperature may have the following effect on compound muscle action potential (CMAP) decrement on repetitive stimulation in a patient with myasthenia gravis] Increase in CMAP decrement Decrease in CMAP decrement Effect of decreased temperature on CMAP decrement is not predictable No change in CMAP decrement None . 10. [In a bipolar montage, if G1 is negative and G2 is positive, the waveform deflection in channel G1–G2 will be] Upward Downward Flat Equipotential None . 11. [Which of the following EEG findings is characteristic of Landau–Kleffner syndrome (LKS)?] Significant non-REM sleep abnormalities Slow spike-wave discharges in wakefulness Burst suppression Normal background None . 12. [Which of the following interpretations of maintenance of wakefulness test (MWT) is false?] Staying awake for all the trials is strong evidence that the subject can maintain wakefulness in all environments Mean sleep latency of less than 8 minutes during the trials indicates an abnormality Mean sleep latency between 8 and 40 minutes has an unclear clinical significance MWT and multiple sleep latency test (MSLT) can be discordant in a significant number of patients None . 13. [All of the following periodic patterns are highly pathognomonic of an underlying neurological disorder except] Periodic generalized sharp waves occurring at 1 Hz frequency and accompanied by occasional myoclonic jerks Periodic generalized sharp waves occurring every 10–15 seconds and accompanied by occasional myoclonic jerks Bitemporal independent periodic lateralized sharp waves at 1–1.5 Hz frequency Left parieto-central periodic lateralized epileptiform discharges (PLEDs) at 1 Hz frequency None . 14. [All of the following statements regarding EEG activity during sleep are true except] K-complex represents a depolarizing–hyperpolarizing sequence within an oscillatory cycle Spindles are generated by the dorsal nucleus of the thalamus Gamma-aminobutyric acid (GABA)ergic neurons underlie generation of sleep spindles Sleep spindles serve to block incoming stimuli to the cortex None . 15. [Increasing the high-frequency filter cutoff will cause the waveform to appear] Sharper Smoother Phase shifted to the right Smaller None . 16. [Significant decrement may be seen on slow repetitive stimulation in which of the following conditions?] Lambert–Eaton myasthenic syndrome (LEMS) Myasthenia gravis Botulism All of the above None . 17. [A 43-year-old male was evaluated for excessive daytime fatigue. Otherwise, he is asymptomatic. He underwent a polysomnogram (PSG), which showed an apnea hypopnea index (AHI) of 4. His hypnogram is shown below. What is the most likely diagnosis? (fig)] Obstructive sleep apnea Restless legs syndrome (RLS) Periodic limb movement disorder (PLMD) Narcolepsy None Comment . 18. [What is the chance that the first routine EEG will be nondiagnostic for epilepsy?] 10% 20% 50% 90% None . 19. [The 2 waveforms below are from iliopsoas muscle during spontaneous activity recordings with different sweep speeds. What do these findings suggest? (fig)] Fasciculation potentials Fibrillation potentials Tremor Myokymia None Comment . 20. [By what age do conduction velocities of motor nerves in a child reach the adult range?] 1 year 2 years 5 years 7 years None . 21. [All of the following are considered risk factors for developing acute quadriplegic myopathy in an ICU setting except] Liver transplant Hemodialysis for end-stage renal disease Prolonged high-dose corticosteroid therapy Sedation with opiates None . 22. [Serial EEGs in a patient with progressively worsening encephalopathy can be characterized by all of the following except] A 6 Hz, medium voltage, reactive posterior dominant rhythm (PDR) A 9 Hz, low-voltage, reactive PDR Frontal intermittent rhythmic delta activity (FIRDA) Continuous generalized asynchronous delta activity None . 23. [In calculating impedance, the inductive reactance is subtracted from the capacitive reactance because] They have the same phase They have opposite phases The capacitive reactance already includes the inductive reactance The inductive reactance is not part of the overall impedance None . 24. [Assume an EEG acquisition system that has a 10-bit analog-to-digital converter (ADC) with a voltage range of –2 mV to +2 mV. What will be the approximate voltage resolution if a 12-bit analog-to-digital converter (ADC) is used instead of the 10-bit ADC in the EEG system?] 1 μV 2 μV 4 μV 16 μV None . 25. [All of the following statements regarding EEG changes observed after carotid crossclamping during carotid endarterectomy are true except] EEG changes usually occur within the first 20 seconds in the majority of patients Decrease of anterior alpha and beta activity on the clamped side suggests ischemia Increase of delta amplitude on the clamped side suggests progression of ischemia Bilateral EEG changes always suggest change in anesthesia or blood pressure None .
