New Quiz 03 Jan Welcome to your Neurophysiology Name Email 1. [Epileptic spikes are characterized by all of the following except] Their duration is 20–70 ms They are felt to be hypersynchronous events They are usually surface negative They increase in frequency before and after seizure None . 2. [A 30-year-old woman presents with increasing fatigue, decreased exercise tolerance, and weakness over the last few years. On examination, she had proximal limb weakness with normal reflexes and sensation. Facial strength was normal. Her forced vital capacity was decreased. Routine motor and sensory nerve studies were normal. Needle EMG revealed short-duration, myopathic motor units in proximal muscles. What additional step during the electrodiagnostic testing would be helpful?] Facial EMG Repetitive stimulation of the facial nerve EMG of the thoracic paraspinal muscles Diaphragmatic EMG None . 3. [A large posterior thalamic hemorrhage can be associated with all of the following except] Intact P14 Absent N18 Absent N20 Absent P22 None . 4. [The P14 component of the median somatosensory evoked potential (SSEP) is] A near-field potential Best seen on the scalp with a cephalic reference Generated by activity in the medial lemniscus Preserved in cervicomedullary lesions None . 5. [All of the following statements regarding somatosensory evoked potentials (SSEPs) are true except] Up to 40% of patients with multiple sclerosis (MS) without sensory symptoms may have abnormal SSEPs The N20 waveform may be abolished by anesthesia Intravenous etomidate decreases the amplitude of cortical potentials Amplitude of cortical potentials may be increased in progressive myoclonus epilepsy syndromes None . 6. [While performing a nerve conduction study, the neurology resident notices that there is an initial positive deflection on a motor nerve study. He would like to repeat the study to eliminate the initial positive deflection. Which of the following is the best suggestion for him?] Move the G1 electrode to the belly of the recording muscle Move the G2 electrode to increase the distance between the G1 and G2 electrodes Move the stimulating electrode to increase the distance between the stimulating and G1 electrode It is common to have an initial positive deflection in motor studies, so there is no need to repeat the study None . 7. [Which of the following EMG findings is most likely in a patient with polymyositis?] Long-duration motor unit potentials with reduced recruitment patterns Short-duration motor unit potentials with reduced recruitment patterns Positive sharp waves/fibrillation potentials and short-duration motor unit potentials Fasciculation potentials and short-duration motor unit potentials None . 8. [Hypnagogic hypersynchrony refers to] Intermittent diffuse slowing during arousal Intermittent bifrontally predominant slow activity upon falling asleep in children Serial runs of K-complexes and spindles High-amplitude slowing intermixed with multifocal sharp waves None . 9. [During a motor nerve conduction study, the sensitivity of the display was changed from 5 mV per division to 1 mV per division. How can this change affect the compound muscle action potential (CMAP)?] Increases the CMAP duration Increases the CMAP amplitude Increases the measured CMAP latency Decreases the measured CMAP latency None . 10. [All of the following statements regarding EEG findings in coma are true except] Generalized burst suppression is invariably associated with poor prognosis regardless of etiology Diffuse monomorphic nonreactive alpha activity can be associated with brainstem lesions or hypoxic-ischemic injury Normal sleep features such as spindles may be seen with cyclic variability A pattern of low-voltage irregular (LVI) activity alternating with high-voltage slowing may be seen in patients with Cheyne–Stokes breathing None . 11. [The following EEG pattern (filter 1–70 Hz) can be seen in all of the following conditionsExcept (fig)] Baclofen toxicity Lithium toxicity Bismuth subsalicylate Creutzfeldt–Jakob disease (CJD) None Comment . 12. [A 25-year-old woman presents with chronic left shoulder pain and sensory symptoms in her hands. On examination, she has atrophy of the thenar and hypothenar muscle groups in the hand. A nerve conduction study was performed. This showed decreased median and ulnar motor amplitudes. Ulnar sensory response was absent whereas median sensory response was normal. Based on these findings, which of the following conditions is likely?] Carpal tunnel syndrome (CTS) C7–C8 radiculopathy Martin–Gruber anastomosis (MGA) and CTS Neurogenic thoracic outlet syndrome None . 13. [Which of the following statements is true about electrical shock?] A current of 100 mA or higher applied to the skin can cause ventricular fibrillation in a patient Using 3-hole electrical receptacles eliminates risk of electrical shock to the patient Human susceptibility to electrical shock is maximal at 70 Hz Indwelling catheters do not pose additional risk for electrical shock None . 14. [All of the following statements are true about frontal arousal rhythm (FAR) except] It may be associated with cerebral dysfunction It consists of trains of delta waves It appears during sleep-to-wake transitions It is mainly seen in children None . 15. [What percentage of the input amplitude will pass at the cutoff frequency of a filter?] 0% 50% 70% 100% None . 16. [Many types of artifacts exist in the ICU setting of physiological and nonphysiological origin. Which of the following is NOT a typical description of the EEG pattern associated with the listed artifact?] Extracorporeal membrane oxygenation (ECMO) is associated with a 1–3 Hz square wave artifact Ventilators can cause artifact that varies widely in morphology, amplitude, and polarity, but can be associated with a faster frequency artifact due to charged water molecules in the ventilator tubing that can be improved by suctioning Mechanical chest percussion device can cause rhythmic 5–6 Hz activity in 1 electrode Cardiopulmonary resuscitation (CPR) can lead to high-amplitude, rhythmic 1–2 Hz activity that is due to movement artifact and is not cerebral activity None . 17. [A 70-year-old man with erectile dysfunction, difficulty walking, and imbalance undergoes Valsalva testing as part of his autonomic study. On tilt table testing, he had more than 50 mmHg drop in systolic blood pressure at 3 minutes. Valsalva waveforms are shown below (from top to bottom, the waveforms indicate systolic blood pressure [BP], mean BP, diastolic BP, and heart rate changes, respectively). What does this study suggest? (fig)] Normal adrenergic function Severe adrenergic failure Severe sudomotor failure Minimal adrenergic failure None Comment . 18. [All of the following statements regarding the mu rhythm are true except] The frequency tends to be in the theta range It is best seen over the central head regions It is associated with the sensorimotor cortex It is generally asymmetrical and asynchronous in distribution None . 19. [Which of the following statements regarding single-fiber EMG (SFEMG) is correct?] Abnormal SFEMG always means there is an underlying neuromuscular junction (NMJ) disorder Normal SFEMG in a weak muscle makes a NMJ dysfunction less likely SFEMG is a very specific but not very sensitive test for NMJ dysfunction With increasing age, jitter remains the same but blocking increases None . 20. [All of the following findings having been associated with epilepsy except] Unilateral temporal intermittent rhythmic delta activity (TIRDA) Bilateral frontal intermittent rhythmic delta activity (FIRDA) Bilateral occipital intermittent rhythmic delta activity (OIRDA) All of the above None . 21. [How does nerve conduction waveform morphology change as the recording electrode is moved farther from the generator?] The latencies are always reliable The potential amplitudes remain constant The waveform rise time becomes sharper The potential’s polarity tends to be positive None . 22. [Alpha rhythm is] Seen in visual, somatosensory, and temporal cortices Neither facilitatory nor inhibitory during attentional processes Generated in the thalamus Generated by the pyramidal neurons in layer VI of the visual cortex None . 23. [A 61-year-old African American man presented with recent onset eyelid droopiness and weakness over 4 weeks. He used to lift heavy weights but recently noticed difficulty lifting small objects above his head. A few days before coming to the hospital, he noticed a mild right eye droop. Initial examination was significant for right eye ptosis, facial weakness, mild weakness of neck flexion, and proximal limb weakness. The rest of the strength examination, reflexes, and sensation were normal. Which of the following tests would be most appropirate to achieve diagnose in this patient?] Antibody testing for voltage-gated calcium channel Acetylcholine receptor (AChR) antibodies and CT scan of chest Muscle-specific kinase antibody (MuSK) and CT scan of chest Paraneoplastic panel and positron emission tomography (PET) scan None . 24. [Excess variability of motor unit potentials is seen in which of the following conditions?] Amyotrophic lateral sclerosis (ALS) Chronic inflammatory demyelinating polyneuropathy (CIDP) Polymyositis Myasthenia gravis None . 25. [Which of the following statements best describes the clinical significance of interictal epileptiform discharges (IEDs)?] About 66% of patients with epilepsy show IEDs on the first routine EEG IEDs may not be seen in certain forms of temporal lobe epilepsy on scalp recordings Frequency of IEDs correlates roughly with seizure frequency Hyperventilation (HV) activates generalized IEDs but not focal IEDs None .
