front 1 Sensory neuron fibers are classified into four major groups primarily by: A. Neurotransmitter and origin | back 1 B. Size and function |
front 2 Largest diameter, proprioception: A. A-delta | back 2 D. A-alpha |
front 3 Proprioception, light touch, deep touch A. A-delta | back 3 C. A-beta |
front 4 Pain, cold temperature, itch A. A-delta | back 4 A. A-delta |
front 5 Smallest diameter, warm temperature, itch A. A-delta | back 5 B. C |
front 6 Compared with smaller unmyelinated fibers, larger myelinated fibers generally conduct: A. More slowly | back 6 B. More rapidly |
front 7 The cell bodies of primary sensory neurons are located in the: A. Ventral horn | back 7 B. Dorsal root ganglion |
front 8 Primary sensory neurons are termed pseudounipolar because they have: A. Two dendrites, no axon | back 8 C. One process splitting in two |
front 9 In a pseudounipolar sensory neuron, one process extends peripherally while the other projects into the: A. Cerebellar cortex | back 9 B. Spinal cord gray matter |
front 10 A band of numbness across the chest corresponds to sensory loss from one spinal root level. This region is called a: A. Myotome | back 10 C. Dermatome |
front 11 The primary axons of the posterior column pathway are best described as: A. Small, unmyelinated pain fibers | back 11 B. Large, myelinated sensory fibers |
front 12 Posterior column fibers first enter the spinal cord through the: A. Ventral root | back 12 C. Dorsal root |
front 13 After entering the spinal cord, first-order posterior column axons ascend in which location before synapsing? A. Contralateral lateral funiculus | back 13 B. Ipsilateral posterior column |
front 14 A lesion interrupts first-order posterior column fibers before they synapse. These axons normally ascend to the: A. Thalamus in pons | back 14 C. Medulla nuclei |
front 15 Which statement correctly describes the organization of the posterior column pathway? A. One tract, one nucleus | back 15 B. Two tracts, two nuclei |
front 16 Sensory fibers carrying proprioception from the lower limb ascend in which fasciculus? A. Fasciculus cuneatus | back 16 C. Fasciculus gracilis |
front 17 Which part of the posterior column contains fibers from the lower limbs and trunk? A. Lateral cuneate portion | back 17 B. Medial gracile portion |
front 18 A lesion damages the nucleus that receives posterior column input from the lower limbs. Which nucleus is affected? A. Nucleus cuneatus | back 18 C. Nucleus gracilis |
front 19 Fibers from the upper limb, upper trunk above T6, and neck ascend in the: A. Medial gracile fasciculus | back 19 B. Lateral cuneate fasciculus |
front 20 Posterior column fibers from the upper limb ultimately synapse on second-order neurons in the: A. Nucleus gracilis | back 20 C. Nucleus cuneatus |
front 21 A hemicord lesion damages the lateral portion of the posterior column at a cervical level. Which sensory region is most affected? A. Lower limb | back 21 B. Upper limb and neck |
front 22 After first-order posterior column fibers synapse in the caudal medulla, the second-order neurons cross the midline as the: A. External arcuate fibers | back 22 C. Internal arcuate fibers |
front 23 Once these second-order neurons decussate in the medulla, they ascend contralaterally as the: A. Medial lemniscus | back 23 A. Medial lemniscus |
front 24 A small lesion selectively damages the ventral portion of the medial lemniscus in the medulla. Which body region’s proprioceptive information is most likely affected? A. Face | back 24 D. Foot and lower limb |
front 25 A small lesion selectively damages the dorsal portion of the medial lemniscus in the medulla. Which body region’s proprioceptive information is most likely affected? A. Face | back 25 B. Upper limb |
front 26 A midbrain lesion damages the lateral portion of the medial lemniscus. Which sensory stream is most likely impaired? A. Facial touch | back 26 C. Lower limb proprioception |
front 27 In the midbrain, fibers from the upper limb are located in which part of the medial lemniscus? A. Medial portion | back 27 A. Medial portion |
front 28 The medial-lateral arrangement of body fibers in the pons and midbrain is best described as: A. Identical to spinal cord | back 28 B. Opposite the spinal cord |
front 29 Second-order neurons of the dorsal column-medial lemniscus pathway synapse on third-order neurons in which thalamic nucleus? A. Ventral posterior medial | back 29 C. Ventral posterior lateral |
front 30 After synapsing in the VPL, body sensory fibers reach cortex by passing through the: A. Posterior limb, internal capsule | back 30 A. Posterior limb, internal capsule |
front 31 Thalamocortical somatosensory projections from the VPL terminate primarily in the: A. Precentral gyrus | back 31 D. Postcentral gyrus |
front 32 Most thalamocortical sensory fibers terminate in which cortical layer of primary somatosensory cortex? A. Layer II | back 32 D. Layer VI |
front 33 Touch sensation from the face reaches the thalamus primarily through the trigeminal lemniscus and then synapses in the: A. VPL nucleus | back 33 D. VPM nucleus |
front 34 A patient loses pain and temperature sensation after injury to the anterolateral pathway. Which tract is primarily involved? A. Dorsal spinocerebellar tract | back 34 C. Spinothalamic tract |
front 35 The primary afferents entering the spinothalamic pathway are best described as: A. Large, heavily myelinated fibers | back 35 B. Small, often unmyelinated fibers |
front 36 Which sensory modalities are primarily carried by the spinothalamic tract? A. Fine touch, vibration, proprioception | back 36 B. Pain, temperature, gross touch |
front 37 First-order spinothalamic fibers enter the spinal cord through the: A. Ventral root | back 37 C. Dorsal root |
front 38 After entering the spinal cord, spinothalamic primary afferents first synapse mainly in which regions? A. Lamina I and V | back 38 A. Lamina I and V |
front 39 A painful stimulus applied to the foot travels in fibers that may ascend or descend a few spinal segments before synapsing. These fibers are traveling in: A. Anterior white commissure | back 39 B. Lissauer tract |
front 40 Which statement best describes the crossing pattern of spinothalamic second-order neurons? A. They cross in medulla | back 40 C. They cross in anterior commissure |
front 41 A right lateral spinal cord lesion at T8 causes loss of left-sided pain and temperature beginning a few segments below the lesion. This occurs because spinothalamic fibers: A. Cross immediately at entry | back 41 B. Cross after 2–3 segments |
front 42 In the spinal cord, lower-limb pain and temperature fibers within the anterolateral white matter are located: A. Most medially | back 42 D. Most laterally |
front 43 In the spinothalamic tract, upper-limb fibers are located: A. Most medially | back 43 A. Most medially |
front 44 Most ascending spinothalamic fibers carrying body sensation synapse in which thalamic nucleus? A. VPM | back 44 B. VPL |
front 45 Some spinothalamic fibers terminate in the intralaminar nuclei of the thalamus, contributing especially to: A. Fine touch discrimination | back 45 B. Emotional arousal of pain |
front 46 Besides the intralaminar nuclei, some spinothalamic fibers also project to the: A. Mediodorsal nucleus | back 46 A. Mediodorsal nucleus |
front 47 After thalamic processing, spinothalamic sensory information ultimately projects to the: A. Precentral gyrus | back 47 C. Postcentral gyrus |
front 48 Besides the spinothalamic tract, which tract in the anterolateral column is most associated with the emotional and arousal aspects of pain? A. Dorsal spinocerebellar tract | back 48 B. Spinoreticular tract |
front 49 Fibers in the spinoreticular tract terminate primarily in the: A. Ventral posterior nucleus | back 49 D. Medullary-pontine reticular formation |
front 50 The medullary-pontine reticular formation projects mainly to which thalamic nuclei in this pain pathway? A. Geniculate nuclei | back 50 B. Intralaminar nuclei |
front 51 Unlike the spinothalamic tract, the spinoreticular tract does not project to cortex in a: A. Bilateral pattern | back 51 B. Somatotopic pattern |
front 52 Diffuse cortical projections from the spinoreticular system are thought to promote: A. Behavioral arousal | back 52 A. Behavioral arousal |
front 53 Which anterolateral tract projects to the periaqueductal gray matter and superior colliculus? A. Spinocerebellar tract | back 53 C. Spinomesencephalic tract |
front 54 The spinomesencephalic tract is most directly involved in: A. Position sense | back 54 B. Central pain modulation |
front 55 In the notes, the spinomesencephalic tract is summarized as helping to: A. Localize pain | back 55 C. Resolve pain |
front 56 del | back 56 del |
front 57 del | back 57 del |
front 58 Somatosensory information from primary cortex is conveyed next to the secondary somatosensory association cortex located in the: A. Sylvian fissure region | back 58 A. Sylvian fissure region |
front 59 The secondary somatosensory association cortex lies in the region called the: A. Uncus | back 59 C. Parietal operculum |
front 60 Further higher-order processing of somatosensory information occurs in the superior parietal lobule, which includes Brodmann areas: A. 9 and 10 | back 60 B. 5 and 7 |
front 61 Cortical sensory loss is most likely caused by lesions of the: A. Basal ganglia and association areas | back 61 C. Somatosensory cortex and association areas |
front 62 Gate control theory proposes that activation of which fibers can reduce pain at the dorsal horn? A. A-delta fibers | back 62 A. A-delta fibers |
front 63 Rubbing or flicking an injured area may lessen pain because nonpain sensory input can: A. Amplify spinothalamic firing | back 63 B. Reduce pain in dorsal horn |
front 64 The periaqueductal gray receives input from the hypothalamus, amygdala, and cortex in order to: A. Initiate voluntary movement | back 64 B. Modulate pain |
front 65 Descending pain inhibition from the periaqueductal gray reaches the dorsal horn through a relay in the: A. Red nucleus | back 65 C. Rostral ventral medulla |
front 66 In this descending pain-modulating system, the rostral ventral medulla uses which neurotransmitter to influence the dorsal horn? A. Serotonin | back 66 A. Serotonin |
front 67 The notes also state that the rostral ventral medulla responds to substance P by projecting which transmitter into the dorsal horn? A. Glycine | back 67 C. Norepinephrine |
front 68 An opioid analgesic reduces pain by acting on receptors distributed throughout which system? A. Corticospinal motor pathway | back 68 B. Pain modulation pathway |
front 69 Opiate receptors are present in many locations, but their highest concentrations are found on the: A. Thalamus and cortex | back 69 D. Peripheral nerves and dorsal horn |
front 70 Which set contains only endogenous opiates? A. Serotonin, dynorphin, glutamate | back 70 C. Enkephalin, endorphin, dynorphin |
front 71 Enkephalins and dynorphins are specifically noted to be present in the dorsal horn and also in the: A. RVM and periaqueductal gray | back 71 A. RVM and periaqueductal gray |
front 72 Which endogenous opioid is specifically associated with the hypothalamus rather than being listed directly in the dorsal horn? A. Dynorphin | back 72 D. Endorphin |
front 73 The hypothalamic location of endorphin is relevant because the hypothalamus is connected to the: A. Ventral posterior nucleus | back 73 B. Periaqueductal gray matter |
front 74 The thalamus is part of which major brain division? A. Mesencephalon | back 74 D. Diencephalon |
front 75 Relative to the midbrain, the thalamus is located: A. Rostral | back 75 A. Rostral |
front 76 Which structure lies ventral to the thalamus? A. Epithalamus | back 76 B. Hypothalamus |
front 77 Nearly all pathways that project to the cerebral cortex do so by first synapsing in the: A. Thalamus | back 77 A. Thalamus |
front 78 In addition to sensory pathways, which motor-related systems relay information to the cerebrum through the thalamus? A. Corticospinal and spinothalamic systems | back 78 B. Cerebellum and basal ganglia |
front 79 Which statement best describes thalamic nuclei? A. All project diffusely only | back 79 D. Some are specific, some diffuse |
front 80 Thalamic nuclei generally receive strong feedback from the: A. Cortical areas they supply | back 80 A. Cortical areas they supply |
front 81 Thalamic nuclei involved in motor and sensory projection are most often: A. Bilateral and diffuse | back 81 B. Localized |
front 82 The internal medullary lamina divides each thalamus by forming a: A. Circular ring | back 82 C. Y-shaped sheet |
front 83 The three main thalamic regions created by this lamina are the: A. Medial, lateral, anterior groups | back 83 A. Medial, lateral, anterior groups |
front 84 The medial geniculate nucleus primarily relays: A. Pain information | back 84 D. Auditory input |
front 85 Diffuse thalamic relays involved in cognition and limbic control, especially with frontal lobe relevance, are strongly associated with the: A. Ventral posterior nucleus | back 85 B. Mediodorsal nucleus |
front 86 In addition to the mediodorsal nucleus, diffuse limbic and cognitive relays also involve the: A. Geniculate nuclei and midline nuclei | back 86 C. Intralaminar and midline nuclei |
front 87 Nearly all sensory modalities except smell and hearing relay to primary cortical areas through the: A. Anterior nuclear group | back 87 D. Lateral nuclear group |
front 88 Output from the cerebellum and basal ganglia heading toward primary motor cortex relays mainly in the: A. Ventral lateral nucleus | back 88 A. Ventral lateral nucleus |
front 89 The anterior nuclear group is best known for relaying: A. Auditory signals | back 89 C. Limbic pathway input |
front 90 The pulvinar nucleus is located in the: A. Posterior thalamus | back 90 A. Posterior thalamus |
front 91 The pulvinar mainly relays visual and other sensory information broadly to: A. Primary motor cortex | back 91 D. Association cortices |
front 92 Thalamic nuclei located within the internal medullary lamina are called: A. Midline nuclei | back 92 B. Intralaminar nuclei |
front 93 The major input to the intralaminar nuclei comes especially from the: A. Hippocampus | back 93 D. Basal ganglia |
front 94 Projections from the intralaminar nuclei to cortex are best described as: A. Strictly somatotopic and widespread | back 94 B. Nonspecific and widespread |
front 95 The intralaminar nuclei are divided into two major subdivisions, the: A. Caudal and rostral groups | back 95 A. Caudal and rostral groups |
front 96 Which caudal intralaminar nucleus is specifically described as very large? A. Mediodorsal nucleus | back 96 D. Centromedian nucleus |
front 97 The rostral intralaminar nuclei help maintain alertness by relaying input from the: A. Spinothalamic pathway | back 97 D. Ascending reticular activating system |
front 98 The rostral intralaminar nuclei also have reciprocal connections with the: A. Basal ganglia | back 98 A. Basal ganglia |
front 99 Nuclei located between the two thalami are called the: A. Midline thalamic nuclei | back 99 A. Midline thalamic nuclei |
front 100 The thalamic reticular nucleus is best described anatomically as a: A. Medial cluster within the thalamus | back 100 B. Thin sheet along lateral thalamus |
front 101 Which statement uniquely distinguishes the thalamic reticular nucleus from other thalamic nuclei? A. It relays auditory input | back 101 C. It does not project to cortex |
front 102 The thalamic reticular nucleus primarily receives input from other thalamic nuclei and sends output: A. Back to the thalamus | back 102 A. Back to the thalamus |
front 103 The neuronal population of the thalamic reticular nucleus is composed predominantly of: A. Cholinergic excitatory neurons | back 103 D. Inhibitory GABAergic neurons |
front 104 A lesion that disrupts the thalamic reticular nucleus would most directly impair which function? A. Regulation of thalamic activity | back 104 A. Regulation of thalamic activity |
front 105 In addition to input from thalamic nuclei, the thalamic reticular nucleus also receives input from the cortex, reticular formation, and: A. Hippocampus | back 105 B. Forebrain |
front 106 Input from the brainstem reticular formation to the thalamic reticular nucleus helps support its role in modulating: A. Fine touch localization | back 106 C. Level of consciousness |
front 107 Which circuit description best matches the thalamic reticular nucleus? A. Excitatory thalamus-to-cortex relay | back 107 B. Inhibitory thalamus-to-thalamus regulator |
front 108 _____ Nuclei= relays inputs from many pathways to the cortex in reciporical fashion. includes medial, lateral, and anteiror nuclear groups | back 108 Relay |
front 109 _____ Nuclei= within the internal medullary lamina of the thalamus and is involved with relay of inputs from the basal ganglia to widespread cortical locations and is involved in relay of ARAS which promotes alertness | back 109 Intralaminar |
front 110 _____ Nucleus= located in sheet lateral to thalamus within its
capsule and has a mainly inihibitory role within the
thalamus relaying thalamic inputs back to the thalamus
and | back 110 Reticular |
front 111 A patient with a lesion in a major somatosensory pathway reports abnormal tingling despite objective sensory loss. This symptom is best described as: A. Dysarthria | back 111 B. Paresthesia |
front 112 A patient with a posterior column lesion reports numbness, tingling, and a tight band-like sensation around the limb. Which lesion location best matches this symptom pattern? A. Posterior column | back 112 A. Posterior column |
front 113 A lesion of the anterolateral column is most likely to produce which abnormal sensory complaint? A. Tight band-like numbness | back 113 C. Sharp, burning pain |
front 114 A patient develops severe contralateral pain after a thalamic stroke. This syndrome is called: A. Brown-Séquard syndrome | back 114 D. Dejerine-Roussy syndrome |
front 115 Flexing the neck causes an electric shock-like sensation running down the back and into both arms. This finding is called: A. Romberg sign | back 115 C. Lhermitte sign |
front 116 A patient has pain and numbness radiating down the lateral leg in a dermatomal pattern, and the pain worsens when the nerve root is stretched. This is most consistent with: A. Mononeuropathy | back 116 B. Radiculopathy |
front 117 Which statement best describes symptoms from a peripheral nerve lesion compared with radiculopathy? A. They never cause numbness | back 117 C. They produce symptoms in the nerve’s region |
front 118 An unpleasant, abnormal sensory experience that is not simply decreased sensation is termed: A. Dysesthesia | back 118 A. Dysesthesia |
front 119 Pain produced by a stimulus that is normally not painful is called: A. Hyperpathia | back 119 B. Allodynia |
front 120 A pinprick that is mildly painful in most people causes an exaggerated painful response in a patient with central sensitization. This is best termed: A. Hyperpathia or hyperalgesia | back 120 A. Hyperpathia or hyperalgesia |
front 121 Decreased sensation on neurologic examination is termed: A. Hypalgesia | back 121 B. Hypesthesia |
front 122 The most common cause of spinal cord dysfunction is: A. Intrinsic demyelination | back 122 C. Extrinsic compression |
front 123 A patient with spinal cord dysfunction is expected to develop both motor and sensory deficits beginning: A. At unrelated random levels | back 123 B. At the same general level |
front 124 Why might the clinical level of motor and sensory deficits not exactly match the anatomical level of spinal cord dysfunction? A. Reflexes bypass the cord | back 124 D. Ascending and descending fibers shift levels |
front 125 Immediately after a traumatic spinal cord injury, a patient has flaccid paralysis, absent deep tendon reflexes, hypotension, and loss of sphincter tone. This phase is called: A. Neuroleptic rigidity | back 125 B. Spinal shock |
front 126 As spinal shock resolves over time, which pattern is most likely to emerge? A. Hyperreflexia and spasticity | back 126 A. Hyperreflexia and spasticity |
front 127 An older patient with long-standing cervical spondylosis develops progressive spinal cord dysfunction over months. This presentation is most consistent with: A. Acute myelitis | back 127 B. Chronic myelopathy |
front 128 A patient lost the ability to walk from tumor-related cord compression before treatment. According to the material, what is the approximate chance of ever regaining walking? A. 20% regain walking | back 128 A. 20% regain walking |
front 129 Degenerative disorders of the spine can produce both upper and lower motor neuron signs because they may compress both the: A. Cerebellum and brainstem | back 129 D. Nerve roots and cord |
front 130 A patient has metastatic spinal cord compression but is still walking. What is the most important management principle from the notes? A. Decompress immediately | back 130 A. Decompress immediately |
front 131 When a compressive spinal tumor is detected and removed before the patient loses ambulation, the expected outcome is best summarized as: A. Most still lose walking | back 131 B. Most keep walking ability |
front 132 The most common site of metastatic tumor causing spinal cord compression is the: A. Epidural space | back 132 A. Epidural space |
front 133 Spinal cord infarction most commonly results from occlusion of which vessel? A. Posterior spinal artery | back 133 D. Anterior spinal artery |
front 134 Occlusion of the anterior spinal artery most classically produces: A. Brown-Séquard syndrome | back 134 C. Anterior cord syndrome |
front 135 Watershed infarcts are infarcts occurring in tissue located: A. Between arterial territories | back 135 A. Between arterial territories |
front 136 Which region is specifically identified as a vulnerable watershed zone in the spinal cord? A. Cervicomedullary junction | back 136 C. Mid-thoracic cord |
front 137 A vascular defect that can be difficult to diagnose yet may cause transient episodes of spinal cord dysfunction is: A. Cavernous malformation | back 137 D. Spinal dural AVM |
front 138 Myelitis is best defined as: A. Inflammation of spinal cord | back 138 A. Inflammation of spinal cord |
front 139 A patient develops rapidly progressive spinal cord dysfunction with fever, elevated WBC count, and bright T2 signal abnormalities on spinal MRI. Which cause is specifically listed in the material? A. Epidural lipomatosis | back 139 C. Epidural abscess |
front 140 If myelitis is not treated immediately, the major feared consequence is: A. Only transient numbness | back 140 B. Irreversible spinal damage |
front 141 A 61-year-old man cannot identify a key placed in his left hand with eyes closed, but pinprick, vibration, and crude touch are largely preserved. The lesion is most likely in the: A. Right primary somatosensory cortex | back 141 A. Right primary somatosensory cortex |
front 142 A patient with a right parietal cortical lesion is most likely to have which sensory deficit pattern? A. Ipsilateral pain and temperature loss | back 142 B. Contralateral sensory deficit predominance |
front 143 Which sensory modalities are often most affected by a lesion of the primary somatosensory cortex? A. Pain and temperature | back 143 C. Discriminatory touch and proprioception |
front 144 A patient has intact primary sensation but cannot recognize numbers traced on the palm and ignores simultaneous stimulation on the affected side. This pattern is most consistent with: A. Cortical sensory loss | back 144 A. Cortical sensory loss |
front 145 A small infarct of the left VPL nucleus would most likely cause: A. Ipsilateral body sensory loss | back 145 B. Contralateral body sensory loss |
front 146 A thalamic lesion extends beyond the VPL/VPM into adjacent structures. Which additional finding may occur? A. Aphasia or neglect | back 146 C. Hemiplegia or hemianopia |
front 147 A lesion of the thalamic somatosensory radiation is most likely to produce sensory loss plus: A. Hemiparesis from corticospinal involvement | back 147 A. Hemiparesis from corticospinal involvement |
front 148 Sensory deficits from lesions of the VPL/VPM nuclei are most often noticed by patients in the: A. Trunk and proximal legs | back 148 B. Hands and face |
front 149 A dorsolateral brainstem infarct causes loss of pain and temperature on the left face and right body. The lesion is most likely in the: A. Right medial medulla | back 149 C. Left lateral pons or medulla |
front 150 The crossed sensory findings in a lateral pontine or lateral medullary lesion are due to involvement of the: A. Medial lemniscus and VPL | back 150 B. Trigeminal nucleus and spinothalamic tract |
front 151 A lesion of the medial medulla involving the medial lemniscus would most likely cause: A. Contralateral vibration and proprioception loss | back 151 A. Contralateral vibration and proprioception loss |
front 152 A diabetic patient reports gradually progressive numbness in both feet that later involves the hands, in a symmetric distal pattern. This is most characteristic of: A. Brown-Sequard syndrome | back 152 D. Distal symmetrical polyneuropathy |
front 153 “Glove and stocking” sensory loss most strongly localizes to the: A. Primary sensory cortex | back 153 B. Nerve roots or peripheral nerves |
front 154 A complete transverse lesion of the thoracic spinal cord would interrupt: A. Only sensory pathways below lesion | back 154 C. All sensory and motor pathways below lesion |
front 155 Which of the following is a recognized cause of a transverse cord lesion? A. Migraine aura | back 155 C. Transverse myelitis |
front 156 A knife wound causes hemisection of the right spinal cord at T10. Which deficit is expected below the lesion? A. Right pain loss only | back 156 D. Right vibration loss |
front 157 In Brown-Sequard syndrome, ipsilateral upper motor neuron weakness results from damage to the: A. Lateral corticospinal tract | back 157 A. Lateral corticospinal tract |
front 158 In Brown-Sequard syndrome, contralateral pain loss is caused by damage to the: A. Posterior column | back 158 C. Anterolateral column |
front 159 A patient with spinal cord hemisection has ipsilateral loss of vibration, light touch, and proprioception below the lesion. The damaged structure is the: A. Anterolateral system | back 159 B. Posterior column |
front 160 Which of the following is a recognized cause of Brown-Sequard syndrome? A. Penetrating injury | back 160 A. Penetrating injury |
front 161 A 29-year-old man develops a spinal cord injury in the cervical region. He loses pain and temperature sensation over both shoulders and arms in a “cape-like” pattern, but other sensory findings are initially limited. Which spinal cord syndrome best explains this pattern? A. Anterior cord syndrome | back 161 C. Central cord syndrome |
front 162 A patient has a small lesion in the center of the spinal cord that damages the crossing spinothalamic fibers. What sensory loss is expected first? A. Bilateral suspended pain loss | back 162 A. Bilateral suspended pain loss |
front 163 A patient with an enlarging central cord lesion develops hand weakness at the level of the lesion and spastic weakness in the legs below the lesion. Which structures are now likely involved? A. Posterior column only | back 163 B. Anterior horn and corticospinal tract |
front 164 A severe central cord lesion causes major loss of pain and temperature below the lesion, but sensation in the sacral area is relatively preserved. This “sacral sparing” is best explained by: A. Lateral sacral fiber location | back 164 A. Lateral sacral fiber location |
front 165 Which of the following is a common cause of central cord syndrome? A. B12 deficiency | back 165 C. Spinal contusion |
front 166 A 55-year-old man has loss of vibration sense and proprioception below a spinal cord lesion. Pain and temperature are preserved. Which syndrome is most likely? A. Posterior cord syndrome | back 166 A. Posterior cord syndrome |
front 167 A patient with untreated vitamin deficiency develops progressive loss of vibration and joint position sense. A large lesion later produces upper motor neuron signs. Which syndrome best matches this presentation? A. Central cord syndrome | back 167 B. Posterior cord syndrome |
front 168 A patient cannot feel pain or temperature below a spinal cord lesion, but vibration and proprioception remain intact. He also develops bowel and bladder incontinence. Which syndrome is most likely? A. Posterior cord syndrome | back 168 C. Anterior cord syndrome |
front 169 Which cause is classically associated with anterior cord syndrome? A. Tertiary syphilis | back 169 C. Anterior spinal artery infarct |
front 170 A patient develops sudden anterior cord syndrome after a vascular event involving the spinal cord. Which artery was most likely affected? A. Anterior spinal artery | back 170 A. Anterior spinal artery |
front 171 Sensory information from the rectum, bladder, and genitals enters the spinal cord through which roots? A. T11-L1 | back 171 C. S2-S4 |
front 172 Sensory signals from the rectum, bladder, and genitals reach higher centers through: A. Dorsal columns only | back 172 D. Both somatosensory pathways |
front 173 Voluntary somatic motor fibers that control the pelvic floor arise primarily from: A. Anterior horn at S2-S4 | back 173 A. Anterior horn at S2-S4 |
front 174 The sphincteromotor nucleus of Onuf primarily controls the: A. Detrusor and trigone | back 174 B. Urethral and anal sphincters |
front 175 Parasympathetic outflow to the pelvis arises from the: A. Intermediolateral column T11-L2 | back 175 D. Sacral nuclei at S2-S4 |
front 176 Sympathetic outflow to the pelvis arises mainly from the: A. Intermediolateral column T11-S2 | back 176 A. Intermediolateral column T11-S2 |
front 177 For a central nervous system lesion to reliably impair bowel, bladder, or sexual function, it usually must be: A. Unilateral and cortical | back 177 C. Bilateral |
front 178 Normal bladder emptying is best described as being under: A. Reflex control only | back 178 B. Voluntary control |
front 179 During normal filling, conscious awareness of bladder fullness depends on sensation reaching the: A. Sensory cortex | back 179 A. Sensory cortex |
front 180 The conscious initiation of voiding begins with activation of the: A. Lateral hypothalamus | back 180 D. Medial frontal micturition centers |
front 181 Which structure is the main regulator coordinating the voiding program once micturition is initiated? A. Onuf nucleus | back 181 C. Pontine micturition center |
front 182 Voluntary relaxation of the external sphincter during urination first helps by: A. Activating sympathetics | back 182 B. Inhibiting internal sphincter sympathetics |
front 183 During normal voiding, parasympathetic activation causes the: A. Detrusor to contract | back 183 A. Detrusor to contract |
front 184 Once urination begins, continued sensation of urine flow mainly: A. Inhibits detrusor contraction | back 184 D. Maintains the voiding reflex |
front 185 When urine flow stops, bladder emptying normally ends because the: A. Pontine center is destroyed | back 185 B. Detrusor relaxes via urethral reflex |
front 186 A patient with bilateral frontal lobe damage urinates automatically when the bladder fills and is unaware of fullness. The damaged area most likely is the: A. Sacral parasympathetic nuclei | back 186 C. Medial frontal micturition centers |
front 187 Bilateral lesions of the medial frontal micturition centers typically cause: A. Overflow retention only | back 187 D. Reflex incontinence without awareness |
front 188 Which condition is a recognized cause of bilateral medial frontal micturition center damage? A. Hydrocephalus | back 188 A. Hydrocephalus |
front 189 A spinal cord lesion below the pontine micturition center but above the conus medullaris first produces which bladder state? A. Spastic bladder | back 189 C. Atonic bladder |
front 190 Weeks after a spinal cord lesion below the pontine micturition center and above the conus medullaris, the bladder most often becomes: A. Permanently areflexic | back 190 B. Hyperreflexive and spastic |
front 191 A patient with an early flaccid neurogenic bladder has marked urinary retention. Which additional finding is most expected in the more severe form? A. Sacral anesthesia only | back 191 C. Bladder distention |
front 192 In a less severe atonic bladder, the patient voids incompletely. Which measurement would be increased? A. Bladder compliance | back 192 B. Post-void residual volume |
front 193 A patient with a spastic neurogenic bladder feels sudden urgency even when the bladder contains only a small amount of urine. What is the main problem? A. Detrusor-sphincter dyssynergia | back 193 A. Detrusor-sphincter dyssynergia |
front 194 In a hyperreflexive bladder, the abnormal urgency is mainly caused by: A. Internal sphincter fibrosis | back 194 B. Detrusor spasms at low volume |
front 195 A hyperreflexive bladder is also called a: A. Atonic bladder | back 195 C. Spastic bladder |
front 196 Which of the following can cause either an atonic bladder or a hyperreflexive bladder? A. Cataracts | back 196 B. Spinal tumors |
front 197 Multiple sclerosis can cause which bladder problem? A. Only stress incontinence | back 197 D. Atonic or hyperreflexive bladder |
front 198 Trauma involving the nervous system can lead to: A. Only spastic bladder | back 198 C. Atonic or spastic bladder |
front 199 Peripheral neuropathies usually cause which bladder pattern? A. Flaccid more than spastic | back 199 A. Flaccid more than spastic |
front 200 In peripheral neuropathy, flaccid bladder commonly occurs because of loss of: A. Sympathetic flow to trigone | back 200 B. Parasympathetic flow to detrusor |
front 201 A patient with diabetic neuropathy develops urinary dribbling from an overfilled bladder. Which diagnosis best fits? A. Stress incontinence | back 201 C. Overflow incontinence |
front 202 Which condition is classically associated with flaccid neurogenic bladder from peripheral nerve involvement? A. Hydrocephalus | back 202 B. Diabetic neuropathy |
front 203 Which lower spinal condition can cause a flaccid bladder? A. Temporal lobe seizure | back 203 C. Cauda equina syndrome |
front 204 A large lumbar disc herniation most commonly causes which bladder pattern if sacral pathways are affected? A. Spastic bladder | back 204 B. Flaccid bladder |
front 205 The term “neurogenic bladder” refers to: A. Only flaccid bladder states | back 205 D. Flaccid or spastic bladder |
front 206 Control of bowel function, like micturition, begins in motor pathways from the: A. Medial frontal lobes | back 206 A. Medial frontal lobes |
front 207 The internal anal sphincter is mainly controlled by: A. Pudendal somatic fibers | back 207 B. Sacral parasympathetics |
front 208 The external anal sphincter is mainly controlled by: A. Sacral parasympathetics | back 208 B. Pelvic nerves from Onuf |
front 209 Pelvic floor muscles are innervated mainly by: A. Sacral anterior horn neurons | back 209 A. Sacral anterior horn neurons |
front 210 Damage to descending motor pathways to the anal sphincters tends to make the sphincters: A. Spastic and continent | back 210 B. Flaccid and incontinent |
front 211 Why can neurological bowel lesions produce constipation as well as incontinence? A. Loss of vagal tone | back 211 C. Loss of parasympathetics to descending colon |
front 212 Parasympathetic stimulation of GI motility proximal to the descending colon is supplied mainly by: A. CN III | back 212 D. CN X |
front 213 Bowel dysfunction of neurological origin can result from damage to which locations? A. Only frontal cortex | back 213 D. Brain, cord, or sacral roots |
front 214 Sensation from the genitals is carried mainly by the: A. Obturator nerve | back 214 B. Pudendal nerve |
front 215 Genital sensory fibers enter the spinal cord primarily at: A. L1-L2 | back 215 C. S2-S4 |
front 216 Genital sensation helps mediate a reflex involving: A. Only somatic pathways | back 216 D. Only autonomic pathways |
front 217 In females, parasympathetic stimulation causes Bartholin glands to: A. Stop secreting mucus | back 217 B. Secrete mucus |
front 218 In females, vaginal secretions are stimulated mainly by: A. Sympathetics | back 218 A. Sympathetics |
front 219 In both sexes, erection is primarily mediated by: A. Sympathetics | back 219 B. Parasympathetics |
front 220 In males, ejaculation is primarily mediated by a: A. Parasympathetic skin reflex | back 220 B. Sympathetic reflex |
front 221 During male ejaculation, which muscle type contracts along the reproductive tract? A. Cardiac muscle | back 221 C. Smooth muscle |
front 222 A spinal cord lesion may affect erection and ejaculation, but the severity is often: A. Fixed and predictable | back 222 C. Variable |
front 223 Which of the following can also contribute to sexual dysfunction besides spinal cord disease? A. Peripheral nerve disease | back 223 A. Peripheral nerve disease |
front 224 Syringomyelia is best defined as a: A. Brainstem aneurysm | back 224 B. Fluid-filled spinal cavity |
front 225 Which of the following is a recognized cause of syringomyelia? A. Congenital abnormalities | back 225 A. Congenital abnormalities |
front 226 Posttraumatic syringomyelia is best described as: A. Immediate spinal hemorrhage | back 226 B. Delayed sequela of SCI |
front 227 About what proportion of spinal cord injury cases develop posttraumatic syringomyelia? A. 10% | back 227 C. 1% |
front 228 Symptoms of posttraumatic syringomyelia arise on average how long after the original injury? A. 9 days | back 228 D. 9 years |