New Quiz 03 Jan Welcome to your Neurophysiology Name Email 1. [Visual evoked potentials (VEPs) may be successfully recorded in patients with visual field defects and impaired visual acuity by] Dilating the pupils Decreasing the check size Placing the recording electrodes more laterally Asking the patient to fixate at different points around the target None . 2. [A 34-year-old male presents with new onset headache and bilateral upper and lower extremity numbness worse on the right side. Median somatosensory evoked potential (SSEP) shows intact potentials with prolonged N9–P14 interpeak latency (IPL) and normal P14–N20 IPL. Which of the following conditions is likely?] Median nerve compression Guillain–Barré syndrome Pontine glioma Thalamic hemorrhage None . 3. [Scoring of a respiratory effort-related arousal (RERA) requires that] The respiratory event last at least 10 seconds There is at least 4% oxygen desaturation There is stable respiratory effort There is flattening of the expiratory portion of the nasal pressure None . 4. [Brainstem auditory evoked potential (BAEP) findings in brain death may include all of the following except] Intact Wave I and absence of other waves Intact Wave II and absence of other waves Intact Waves I and II and absence of other waves Absence of all waveforms None . 5. [A 20-year-old college student presents with difficulty walking for 5 years but recently developed an increased tendency to trip and fall along with mild weakness in her hands. She also reports mild numbness in her feet. She denies any pain. Her birth and initial development were normal, but as a child she did not perform well in sports. On examination, cranial nerves are normal. Proximal limb strength is normal. She has distal weakness with bilateral foot drop and moderate finger extension and abduction weakness. She also has high-arched feet and atrophy of foot intrinsic muscles. Deep tendon reflexes are absent and there is lengthdependent sensory loss. Based on the history, examination, and the above nerve conduction study, what is the most likely diagnosis in the above patient?] Acquired demyelinating polyneuropathy Hereditary demyelinating polyneuropathy Acquired axonal polyneuropathy Distal myopathy None . 6. [The accessory peroneal nerve supplies which of the following muscles?] Peroneus brevis Tibialis anterior Tibialis posterior Extensor digitorum brevis None . 7. [On postoperative day 2 after a renal transplant, a 12-year-old boy became febrile anddeveloped altered mental status. He was placed on antibiotics and continuous video-EEG monitoring was obtained as shown below (filter 1–70 Hz; sensitivity 10 μV/mm;solid vertical bars are 1 second apart). Six hours into the monitoring session, a relativelyabrupt decrease in EEG amplitude was seen as shown below. What is the most likelycause of the change? (fig)] Cessation of a generalized seizure discharge Suctioning the patient Cerebral hypoperfusion Turning off propofol None Comment . 8. [Which sleep state is least likely to show epileptiform abnormalities?] N1 N2 N3 REM None . 9. [All of the following statements about the amplifier are true except] Its gain is given by the ratio Vout/Vin of the signal Its gain is commonly expressed in decibels Its dynamic range is the voltage range over which it behaves linearly Its gain is directly proportional to sensitivity None . 10. [A 40-year-old man recently had a knee injury and noticed weakness in his right leg. Thefindings on peroneal motor study are shown below. What does this suggest? (fig)] Peroneal mononeuropathy at the fibular head Peroneal mononeuropathy at the ankle Normal variant Peroneal mononeuropathy above the popliteal fossa None Comment . 11. [A 64-year-old man is undergoing continuous upper and lower somatosensory evoked potential (SSEP) monitoring during cervical decompression. The intraoperative monitoring (IOM) technologist annotated on the screen that the patient just received a bolus of pentobarbital. What significant change to the subcortical potentials is most likely?] Decreased amplitude Increased latency Decreased latency No change None . 12. [Which of the following is true regarding the relative intracellular and extracellular potential difference across the membrane?] Intracellular polarity is negative during maximal sodium influx Extracellular polarity is positive during hyperpolarization Extracellular polarity is negative during the resting state The intracellular and extracellular potentials are isoelectric during the resting state None . 13. [Which of the following statements is true about steroid induced myopathy?] Type 1 muscle fiber atrophy is seen on muscle biopsy Type 2b muscle fiber atrophy is seen on muscle biopsy Irritative changes with positive sharp waves and fibrillation potentials are seen on EMG Nonflourinated corticosteroids are more likely to cause myopathy than fluorinated corticosteroids None . 14. [What types of signals are used in the calibration process for EEG?] Square wave inputs Sine wave inputs Cosine wave inputs Triangular wave inputs None . 15. [Intraoperative monitoring (IOM) of somatosensory evoked potentials (SSEPs) can reliably detect neural pathway compromise in all of the following surgical procedures except] Total hip arthroplasty Carotid endarterectomy Resection of parietal glioma Reduction of pelvic fracture None . 16. [Which of the following sleep disorders is known to predominantly manifest in the sleepstage as depicted in the 30-second epoch below? (fig)] Bruxism Sleep-related rhythmic movement disorder (head banging) Sleep terror Hypnic jerks None Comment . 17. [A 35-year-old man had extensive injuries in a motor vehicle accident. A few weeks after discharge from the intensive care unit, while underlying rehabilitative therapy, he was noted to have significant weakness in the right upper limb. Findings on needle EMG are shown in the table below. What is the best localization based on these findings? (fig )] Lateral cord Medial cord Posterior cord Lower trunk None Comment . 18. [A 30-year-old man initially noticed difficulty walking and tendency to fall in his late teenage years, followed by gradual progression of his condition over the next decade. On examination, he has severe spasticity in his lower limbs and sensorimotor neuropathy. His 28-year-old brother also has similar manifestations. Electrodiagnostic study in this patient will most likely reveal] Normal nerve conduction studies Primarily low compound muscle action potential (CMAP) amplitude with mild slowing Severe slowing of conduction velocity with mildly decreased amplitudes Normal nerve conduction studies but severe proximal denervation on needle EMG None . 19. [What is the best interpretation of the posterior activity seen on the following EEG (filter 1–70 Hz; sensitivity 15 μV/mm; solid vertical lines are 1 second apart) of a 4-year-old boy? (fig)] Posterior slow waves of youth Lambda waves Occipital spike-wave discharge Normal posterior dominant rhythm (PDR) None Comment . 20. [A 9-year-old girl with staring spells had an EEG that showed high-amplitude, 3–4 Hz sharply contoured delta activity. In which of the following scenarios would this finding always be pathological?] Hyperventilation (HV) Drowsiness Photic stimulation Slow wave sleep None . 21. [Which of the following muscles is innervated by the peroneal nerve above the level of the fibular head?] Semimembranous Semitendinosus Long head of biceps femoris Short head of biceps femoris None . 22. [A 40-year-old obese female with hypertension, hypothyroidism, and excessive daytimesleepiness undergoes an overnight polysomnogram (PSG). Two consecutive 30-secondepochs are shown below. Which of the following statements best describes the sleepstage? Note that the thick vertical line separates the two epochs. (fig)] 1st epoch is Stage N2, 2nd epoch is Stage REM 1st epoch is Stage N2, 2nd epoch is Stage W 1st epoch is Stage REM, 2nd epoch is Stage REM 1st epoch is Stage N1, 2nd epoch is Stage REM None Comment . 23. [A 27” computer screen has a resolution of 1920 (horizontal) by 1080 (vertical) pixels with vertical borders of 250 pixels each. An EEG sampled at 1000 Hz is displayed at 15 seconds per page. What would be the maximum resolvable frequency if the margins of the screen are eliminated and the number of seconds per page is reduced from 15 seconds to 10 seconds?] 47 Hz 96 Hz 192 Hz 500 Hz None . 24. [Which of the following medications in therapeutic doses causes abnormalities in brainstem auditory evoked potential (BAEP) waveforms?] Barbiturates Benzodiazepines Chloral hydrate Carbamazepine None . 25. [Motor evoked potentials (MEPs) during scalp transcranial electrical stimulation (TES) are generated by] Action potentials that are initiated at the axon hillocks of the cortical pyramidal neurons Action potentials that are initiated in the cell bodies of the cortical pyramidal neurons The outward transmembrane current under the anode The inward transmembrane current under the cathode None .
