Neuroanatomy Test II Quiz I Motor Tracts

A 47-year-old welder presents at the Emergency Department with sudden onset of difficulty
speaking. The examination reveals slurred speech, deviation of the tongue to the right on
attempted protrusion, and weakness of the lower facial muscles also on the right. CT shows a
well-localized hemorrhagic lesion that is most likely located in which of the following?

Which of the following is the receptor for the afferent limb of the patellar tendon reflex or the jaw
jerk reflex?

Which of the following is a sign that would most likely be seen in a patient with a lower motor
neuron lesion?

The MRI of a 71-year-old man suggests a small vascular lesion affecting the structure indicated
by the arrow in the image below. Which of the following would you most likely expect to see in
this patient?

The MRI of a 56-year-old man presents with a sudden loss of motor function of his right hand.
The MRI reveals a circumscribed cortical lesion, most likely hemorrhagic in origin. Which of the
following represents the most likely location of this lesion?

A Neurologist sees three patients in her clinic. These are a 23-year-old man with a Brown-
Séquard syndrome resulting from trauma at C3-5, a 69-year-old woman with a Wallenberg
syndrome, and a 79-year-old man with a hemorrhagic stroke in the lateral portions of the pontine
tegmentum. In addition to the expected deficits, a careful examination would also reveal which of
the following in all three patients?

Which of the following encodes the rate of change in muscle length during contraction of a
skeletal muscle?

A 37-year-old woman presents to her family physician with intermittent physical problems. She is
referred to a neurologist and, after a thorough examination, a tentative diagnosis of multiple
sclerosis is made. MRI shows an area of demyelination in the region indicated by the arrow in
the image below. Which of the following deficits would correlate most specifically with the
location of this lesion?

A 67-year-old man presents at the Emergency Department with a medial medullary (Dejerine)
syndrome. He has a right-sided weakness of the UE and LE, a right-sided loss of vibratory sense
and discriminative touch, and a deviation of the tongue to the left on attempted protrusion.
Weakness of which of the following muscles would explain the asymmetrical tongue movement in
this man?

A 47-year-old man is brought to the Emergency Department from the site of a motor vehicle
collision. The examination reveals facial injuries with a probable broken nose, a compound
fracture of the left humerus, and large bruises/contusions on his left thigh. CT confirms these
observations and shows a skull fracture in the left frontal region, extensive intracranial
hemorrhage, a fracture through the left orbit, and a fractured pelvis. The man is unconscious and
within 6 hours exhibits decorticate posturing. Excessive action in which of the following
tracts/systems would explain the flexion of the upper extremities in this man?

A 71-year-old woman presents to her family physician with difficulty swallowing and some
numbness on her face. The history reveals that this was a sudden onset (2 days ago), and that the
woman not only had difficulty swallowing but also complained that she got food “down the
wrong tube.” The examination revealed a loss of sensation on the right side of the face, some
moderate sensory loss on the left side of her body, and a weak right vocal fold (endoscopic
observation). MRI showed a lesion in the territory of the posterior inferior cerebellar artery
(PICA). Damage to which of the following structures would explain this motor deficit in this
patient?

A 51-year-old woman awakens in the morning and has some difficulty talking. Her daughter
takes her to the Emergency Department. The history reveals that the woman takes medication for
diabetes and for elevated blood pressure, and is significantly overweight. The results of the
examination suggest the probability of a small stroke; MRI shows a lesion localized to the area
indicated by the arrow in the image below. Which of the following deficits would most likely be
seen in this patient based on the location and extent of the damage?