Download Exam 2 2000

NAME _____________________________
BRAIN AND BEHAVIOR I
Monday, May 15, 2000
For all the following questions, indicate the letter that corresponds to the SINGLE MOST
APPROPRIATE ANSWER.
1.
Corticospinal fibers can be injured in a lesion of the
*
A.
B.
C.
D.
E.
2.
*
In an examination for resting muscle tone, a physician slowly moves the limb of a patient
in order to detect resistance to passive movement resulting from
A.
B.
C.
D.
3.
*
4.
*
tegmentum of the pons.
reticular formation of the medulla.
lateral column (funiculus) of the spinal cord.
roof of the midbrain.
dorsal column (funiculus) of the spinal cord.
corticospinal tract excitation.
excitatory signals from output neurons in the vestibular and pontine
reticular nuclei.
increased firing of afferents from the Golgi tendon organ.
excitation of vestibular afferents.
Two-year-old children should be able to copy a
A.
B.
C.
D.
E.
cross.
square.
diamond.
circle.
triangle.
Symptoms of unilateral cerebellar lesions include ipsilateral
A.
B.
C.
D.
E.
loss of position sense.
hypertonia.
paralysis.
intention tremor.
hemiballism.
5.
*
6.
*
7.
*
8.
*
As a medical student who has just arrived on the pediatric neurology service, you review head
scans of patients on your ward. You conclude that the patient whose image is shown in "P" on
your Image Collection Page MOST LIKELY has symptoms that include
A.
B.
C.
D.
E.
visual field defects.
weakness of the upper limbs.
decreased pain sensation in the face.
abnormal pupillary light reflexes.
fasciculations of the deltoid muscles.
Fibers in the internal capsule include axons that descend from the cerebral cortex to synapse
directly on all of the following structures EXCEPT
A.
B.
C.
D.
E.
neurons in the facial motor nucleus.
gamma motor neurons in the spinal cord.
anterior horn cells in the spinal cord.
neurons in the vestibular nuclei.
interneurons in the spinal cord.
An 18-year-old male was brought to the emergency department following a motor vehicle
accident. He was comatose on entrance into the facility. On clinical examination, he had an
extension of both the left lower limb and left upper limb on painful stimulation of the nail beds
of the left hand. This finding could be caused by a lesion at the level of the
A.
B.
C.
D.
E.
internal capsule.
diencephalon.
cerebral cortex.
medulla.
rostral pons.
After a viral infection, a 24-month-old girl is hospitalized with idiopathic thrombocytopenia
purpura (autoimmune disorder whereby antibodies destroy platelets, placing the person at risk
for uncontrolled bleeding and death). What is the MOST LIKELY concern of this hospitalized
24-month-old girl?
A.
B.
C.
D.
E.
Gender identity
Separation from friends
Loss of identity
Death and dying
Intactness of the body
2
9.
*
10.
*
A lesion of the entire right inferior colliculus will MOST LIKELY result in
A.
B.
C.
D.
E.
a right sided sensory deafness.
tinnitus and a sense of fullness in the right ear.
vertigo and nausea.
difficulty in locating the source of a sound.
conduction deafness on the right side.
Which of the following develops first in the infant?
A.
B.
C.
D.
E.
Stranger anxiety
Social smile
Gender identity
Social referencing
Separation anxiety
11.
An ischemic infarct limited to the right inferior cerebellar peduncle would lead to central
chromatolysis in all of the following structures EXCEPT the
*
A.
B.
C.
D.
E.
12.
All the following statements about sound transduction in the cochlea are correct EXCEPT that
A.
B.
C.
D.
*
E
right interposed nuclei.
left inferior olivary nucleus.
right Clarke's nucleus.
right fastigial nucleus.
right vestibular ganglion.
once per cycle of the sound wave, the basilar membrane deflects upward (toward the
scala vestibuli).
when a stereocilium is deflected in the outer direction, the channels open more and allow
an influx of K+ from the endolymph.
deflecting the stereocilium in the inner direction hyperpolarizes the hair cell.
hair cells are electrically resonant and designed to support voltage oscillations at a certain
frequency.
because Type II fibers of the auditory nerve are not convergent, the inner hair
cells provide the best information about frequency.
3
13.
The figure above shows the circuitry of the DIRECT and INDIRECT pathways of the motor
(skeletomotor) loop through the basal ganglia. The projections of the pathways are labeled with a
number. Which inhibitory pathway would show INCREASED activity and produce the
hypokinesia characteristic of Parkinson's disease?
*
A.
B.
C.
D.
E.
1
2
3
4
5
14.
Cooperative play begins at age (in years) of
*
A.
B.
C.
D.
E.
three.
two.
four.
five.
six.
4
15.
A stroke (lacunar or small infarct) in the left posterior limb of the internal capsule would result in
the greatest disability of which of the following activities?
*
A.
B.
C.
D.
E.
16.
During testing for the biceps jerk reflex, your goal is to cause an increase in the
A.
B.
C.
*
D.
E.
Closing the left eye
Sitting up in bed
Screwing the top on a catsup bottle with the right hand
Chewing an apple
Closing the right eye
firing rate of gamma motor neurons.
firing rate of afferent fibers from Golgi tendon organ receptors.
firing rate of GABAergic interneurons that terminate on motor neurons to the biceps
muscle.
contraction of intrafusal muscle fibers.
opening of ion channels in dynamic nuclear bag receptors in the biceps muscle.
17.
A stroke that resulted in right-sided weakness (hemiparesis) which is more marked (greater) in
the arm than in the leg suggests that the site of the occlusion is MOST LIKELY in the
*
A.
B.
C.
D.
E.
18.
A 48-year-old male was examined by you, his physician, with generalized complaints about
"feeling funny." After taking his history, you suspect a lesion of the nervous system. In the
sensory part of the neurologic exam, you find a loss of pain and temperature on the right upper
and lower limbs and on the left side of his face. You suspect a lesion of the left side of the
tegmentum of the medulla and expect to see an abnormal
*
A.
B.
C.
D.
E.
middle cerebral artery.
basilar artery.
AICA.
posterior cerebral artery.
anterior cerebral artery.
gag reflex.
pupillary light reflex.
knee jerk reflex on the right side.
knee jerk reflex on the left side.
corneal reflex.
5
19.
*
20.
*
The stereocilia on a hair cell near the base of the cochlea
A.
B.
C.
D.
E.
are embedded in or just beneath the basilar membrane.
respond best to sound of a particular high frequency.
transduce sound stimuli using a second-messenger mechanism.
are bathed in perilymph, a normal extracellular fluid.
are longer than stereocilia near the apex of the cochlea.
A patient presents with a wide-based, ataxic gait during his attempts at walking. He also is
unsteady and sways when standing and displays a tendency to fall backward or to either side in a
drunken manner. A lesion is MOST LIKELY located in the
A.
B.
C.
D.
E.
hemispheres of the posterior cerebellar lobe.
anterior limb of the internal capsule.
dentate nucleus.
anterior lobe of the cerebellum.
flocculonodular lobe of the cerebellum.
21.
An 8-year-old boy was admitted to the Children's Hospital Psychiatric unit because of
threatening to run away and kill himself. His mother reported changes in his behavior over the
last month including poor eating, sleeplessness, and dropping grades. Based on Erickson's theory
of development, the boy is MOST LIKELY to experience his hospitalization as a
*
A.
B.
C.
D.
E.
22.
The above patient, while in the hospital, uncharacteristically defecated in his pants. He also
repeatedly attempted to sit on the nurse's lap for comfort. He had a temper tantrum after he was
asked to share a toy. Which of the following best describes this behavior?
*
A.
B.
C.
D.
E.
sign of his inferiority.
punishment for misbehavior.
traumatic separation from his mother.
threat to his identity.
decrease in generativity.
It is a normal response to psychiatric hospitalization.
It is a passive-aggressive expression of his anger.
It is developmental regression.
It is an example of bargaining.
It is reaction formation.
6
23.
The initial sign of puberty in females is
*
A.
B.
C.
D.
E.
24.
After an injury to the inferior temporal area, a patient would MOST LIKELY have a(an)
*
25.
*
A.
B.
C.
D.
E.
a growth spurt.
menarche.
breast bud development.
pubic hair.
axillary hair.
Broca's aphasia.
Wernicke's aphasia.
motor apraxia.
agnosia.
dysphagia.
An eight-year-old boy's normal development is MOST LIKELY to be characterized by
A.
B.
C.
D.
E.
ability to understand abstract ideas.
lack of sexual exploration.
difficulty grasping game rules.
preference for single-sex groups.
presence of a growth spurt.
(Questions # 26 and 27):
For each of the definitions listed below, select the defense mechanism being described.
A.
B.
C.
D.
E.
Denial
Repression
Reaction Formation
Sublimation
Displacement
26.
Distortion of external reality.
A
27.
An idea or feeling is kept out of consciousness.
B
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28.
*
29.
*
30.
*
A 56-year-old mechanic joined your HMO. He has a history of a stroke of the left internal
capsule, which occurred six years previously. On physical examination, you expect that he is
MOST LIKELY to exhibit which of the following clinical signs?
A.
B.
C.
D.
E.
Hypotonia of the left upper limb
Hyporeflexia of the right lower limb
Hyporeflexia of the right upper limb
A right Babinski sign
Fibrillations of the left gastrocnemius muscle
In an unconscious patient in the emergency department, you lightly touch the cornea of one
eyeball with a Q-tip. This is done to test a reflex whose afferent limb includes a branch of the
A.
B.
C.
D.
E.
facial nerve.
abducens nerve.
oculomotor nerve.
optic nerve.
trigeminal nerve.
The central pattern generator that sends signals to lower motor neurons for stepping (walking)
are located in the
A.
B.
C.
D.
E.
pons.
lumbosacral area of the spinal cord.
paracentral lobule of the cerebral cortex.
cervical area of the spinal cord.
vestibular nuclei.
31.
The dorsal root ganglia are to the cuneate nuclei as the spiral ganglia are to the
*
A.
B.
C.
D.
E.
vestibular nuclei.
vestibular (Scarpa's) ganglia.
abducens nuclei.
superior olivary complex.
cochlear nuclei.
8
32.
*
33.
You perform the Rinne test on a 35-year-old male and determine that the patient hears better
with the tuning fork applied to the mastoid process than when you hold it in the air beside his
ear. You conclude that
A.
B.
C.
D.
E.
All of the following statements concerning the cerebellum are correct EXCEPT that
A.
B.
C.
*
D.
E.
34.
the patient's hearing is normal.
the patient has a cochlear nerve lesion.
the auditory nerve has been damaged.
the patient has a conduction lesion.
there is a central auditory processing disorder.
the deep cerebellar nuclei receive both sensory information and information about
motor commands.
it makes use of lateral inhibition.
parallel fiber input can affect groups of muscles that are arranged sequentially along an
extremity.
LTD results from a strengthening of the AMPA-mediated current at the parallel fiberPurkinje cell synapse.
Purkinje cells in the flocculus can directly inhibit the firing rate of neurons in the
vestibular nuclei during the vestibulo-ocular reflex.
A 62-year-old male had a hypertensive stroke. Three days later, when asked where he lived, he
said to the examiner, "I liffe in Hitherg, Hensylhania." Which of the following is LEAST
LIKELY to be the site of the stroke?
*
A.
B.
C.
D.
35.
Among adolescents which of the following is true?
*
A.
B.
C.
D.
E.
Internal capsule
Primary motor cortex
Cerebral peduncle (basis pedunculi)
Broca's motor speech area.
The leading cause of death is suicide.
Cognitive development is characterized by formal operational thinking.
Boys tend to mature earlier than girls.
The most common substance abuse problem involves cocaine.
Serious emotional problems are common.
9
(Questions #36-37):
A patient suffered a stroke in the area shown by the hatching below. The patient died three months after
the stroke.
36.
*
37.
*
Symptoms from the above lesion include
A.
B.
C.
D.
E.
flaccid paralysis of the muscles of the right hand.
spastic paralysis of the muscles of the left foot.
decreased muscle tone of the right lateral rectus muscle of the eyeball.
inability to localize stimuli presented to the left hand.
blindness.
Following the death of this patient, sections taken from the CNS and stained for myelin would
show demyelination in the
A.
B.
C.
D.
E.
tegmentum of the midbrain.
left dorsal column of the spinal cord.
right inferior cerebellar peduncle.
right cerebral peduncle.
left posterior limb of the internal capsule.
10
A
(Questions # 38
and 39):
B
38.
*
39.
*
A patient presents with involuntary rapid, flick-like movements of the limbs. Family history
reveals that the patient's father and grandfather both exhibited the same symptoms.
Neuroimaging for this patient is shown above (B) compared to a similar scan from a normal
individual (A). The MOST LIKELY cause of his pathology is due to loss of
A.
B.
C.
D.
E.
dopaminergic cells in the substantia nigra.
neurons in the primary motor cortex.
neurons of the subthalamic nucleus.
medium spiny neurons in the striatum.
glutamatergic neurons in the VL nucleus of the thalamus.
The imaging technique used to produce the image labeled "A" above
A.
B.
C.
D.
E.
is T1-weighted.
is T2-weighted.
uses ionizing radiation.
detects single photon radiation.
readily detects calcification
11
40.
*
41.
*
During manual muscle testing you determine that your patient has weakness of the triceps
muscle and a reduced triceps reflex. All other muscle groups in the upper extremity are normal.
A nerve root injury may be present at the spinal cord level of
A.
B.
C.
D.
E.
C-2.
C-5.
C-7.
C-8.
T-1.
A 72-year-old man with prostate cancer has had increasingly severe back pain for two months
and trouble walking for two days. He makes an appointment to see you for an examination. He
is a private individual and becomes upset with his wife when she volunteers that he lost control
of his urine last night. On examination, you find that his mental status, cranial nerve function,
and upper extremity strength are all normal. In both lower extremities he has weakness,
abnormally brisk reflexes, and Babinski signs. He cannot feel the sharpness of a safety pin when
you drag it anywhere below his umbilicus. Based on these findings, you localize the lesion to
the
A.
B.
C.
D.
E.
peripheral nervous system (peripheral neuropathy beginning in the legs)
spinal cord (lumbar level)
peripheral nervous system (multiple lumbosacral radiculopathies)
spinal cord (thoracic level)
cerebral hemisphere (bilateral rostral paracentral lobules)
42.
A patient was admitted to the Emergency Department of University Hospital with a constellation
of neurologic deficits that included a left hemiplegia, left hemianesthesia, and left homonymous
hemianopsia. All of these neurologic deficits could result from an occlusion of the right
*
A.
B.
C.
D.
E.
anterior choroidal artery.
superior cerebellar artery.
recurrent artery of Heubner.
lenticulostriate arteries.
posteromedial group of penetrating arteries.
12
43.
Fibrillation potentials
A.
B.
C.
*
D.
E.
44.
are the result of spontaneous action potentials in a degenerating axon stimulating the
contraction of a motor unit.
are one of the earliest signs of muscle denervation.
can occur as a result of any disease that produces degeneration or irritation of the upper
motor neurons.
result from denervated muscle fibers expressing fetal acetylcholine receptors and voltagegated Na+ channels.
are the basis for the interference pattern seen during a needle exam as the muscle being
tested gradually contracts.
During a soccer game a 17-year-old male was knocked to the ground, striking his head. He was
unconscious during the ambulance ride to the Emergency Department. Six hours later he
regained consciousness and a neurological examination was conducted. The following deficits
were noted by the examiner: an inability to recognize the position of both upper limbs and both
lower limbs; an inability to voluntarily move the upper limbs or the lower limbs; and a
loss of vibratory sense over the entire body except for the face. He responded to pin prick testing
in all limbs.
Assuming a single lesion is responsible for these neurologic deficits, which of the following
structures have MOST LIKELY been affected by this lesion?
*
A.
B.
C.
D.
E.
Left thalamus and left posterior limb of the internal capsule
Right precentral and postcentral gyri
Decussation of the internal arcuate fibers and the pyramidal decussation
Fasciculus gracilis bilaterally and fasciculus cuneatus bilaterally
Right cerebral peduncle and right medial lemniscus
45.
Output (efferent projections) from the GPi/m and/or SNpr go DIRECTLY to all the following
areas EXCEPT the
*
A.
B.
C.
D.
E.
spinal cord.
thalamus.
pedunculopontine nucleus.
superior colliculus.
habenular nucleus.
13
GROSS ANATOMY EXAMINATION
May 15, 2000
For the following questions, indicate the letter that corresponds to the SINGLE MOST APPROPRIATE
ANSWER
46.
*
47.
*
48.
*
49.
*
Pain associated with an infection limited to the middle ear cavity results from impulses carried
along the
A.
B.
C.
D.
E.
chorda tympani nerve.
great auricular nerve.
vagus nerve.
glossopharyngeal nerve.
mandibular division of the trigeminal nerve.
All of the following structures are usually supplied by branches of the maxillary artery EXCEPT
the
A.
B.
C.
D.
E.
masseter muscle.
cranial dura mater.
temporomandibular joint.
lower teeth.
scalp.
An otolaryngologist examined the tympanic membrane of a patient with a middle ear infection.
She recalled that the tympanic membrane
A.
B.
C.
D.
E.
is crossed on its lateral surface by the chorda tympani nerve.
is attached to the malleus.
is a partition between the external and internal auditory meatuses.
forms most of the medial wall of the tympanic cavity.
directly transmits vibrations to the round window.
While removing a schwannoma of the vagus nerve, as it exits the skull at the jugular foramen,
the superior cervical ganglion was inadvertently destroyed. This could result in
A.
B.
C.
D.
E.
a dilated pupil in normal light.
moderate drooping of the eyelid.
an increase in the heart rate.
increased sweating of the face.
decreased blood flow of the superficial facial arteries.
14
50.
All of the following statements concerning the middle ear cavity are correct EXCEPT that it
*
A.
B.
C.
D.
E.
51.
*
contains the stapedius muscle that is innervated by the facial nerve.
communicates with the nasopharynx via the auditory tube.
contains a tympanic plexus that includes fibers from the vagus nerve.
is separated from the middle cranial fossa by the tegmen tympani.
contains a bulge on its medial wall that is caused by the basal turn of the cochlea.
A 27-year-old man was struck on the side of his head with a hockey stick, fracturing the ramus
of his mandible. On resecting fragments of the ramus, the plastic surgeon noted blood oozing
from the pterygoid plexus, just medial to the bone fragments. The surgeon was concerned about
the development of infection because he knew that the plexus had direct connections with all of
the following structures EXCEPT the
A.
B.
C.
D.
facial vein.
cavernous sinus.
inferior ophthalmic vein.
sigmoid sinus.
52.
A bullet that passes through the posterior belly of the digastric muscle would damage all of the
following structures EXCEPT the
*
A.
B.
C.
D.
E.
53.
An oral surgeon corrected the malocclusion of a patient by repositioning the articular disk of the
right temporomandibular joint. He knew that a muscle which attaches to the disk is the
*
A.
B.
C.
D.
E.
superior thyroid artery.
hypoglossal nerve.
internal jugular vein.
external carotid artery.
superior root of the ansa cervicalis.
medial pterygoid.
temporalis.
masseter.
buccinator.
lateral pterygoid.
15
54.
*
55.
*
56.
*
57.
*
"Shingles" is a painful skin disorder that results from a viral infection in the cell bodies of
sensory neurons. In a patient with skin blisters over the lower jaw, temporal region, and the area
anterior to the external ear, the viral infection is located in the
A.
B.
C.
D.
E.
otic ganglion.
trigeminal ganglion.
ciliary ganglion.
superior cervical ganglion.
geniculate ganglion.
A thyroidectomy is performed to remove a tumor. During the procedure, the surgeon
remembered that all of the following statements regarding the thyroid gland are correct EXCEPT
that
A.
B.
C.
D.
E.
it is enveloped by pretracheal fascia.
it is located inferior to the thyroid cartilage.
the isthmus crosses the 2nd and 3rd tracheal cartilages.
the left and right lobes are posterior to the sternothyroid muscle.
it is drained by veins that empty into the external jugular vein.
A 35-year-old woman complained to her physician that her left hand felt colder than her right.
The doctor suspected that the left subclavian artery may be compressed. The MOST LIKELY
place where this artery could be compressed is
A.
B.
C.
D.
E.
against the clavicle lateral to the sternocleidomastoid muscle.
in the suprasternal notch.
as it comes off the brachiocephalic artery.
as it travels posterior to the anterior scalene muscle.
just above the sternoclavicular joint.
Following an injection of a local anesthetic agent around the mandibular division of the
trigeminal nerve (CN V3) as it exits the skull, all of the following would occur, EXCEPT
A.
B.
C.
D.
E.
loss of sensation to the lower teeth and skin covering the mandible and chin.
paralysis of the anterior belly of the digastric muscle.
paralysis of the lateral and medial pterygoid muscles.
paralysis of the temporalis muscle.
paralysis of the buccinator muscle.
16
58.
*
59.
*
60.
*
61.
*
During exploratory surgery of the posterior triangle of the neck, a surgeon is aware that all of the
following relationships regarding this triangle are correct EXCEPT that
A.
B.
C.
D.
E.
it contains the accessory nerve
it is bound anteriorly by the posterior border of the sternocleidomastoid muscle.
its base is formed by the middle 1/3 of the clavicle.
it contains the ansa cervicalis.
it contains the lesser occipital nerve.
An aneurysm at the bifurcation of the common carotid artery could compress and damage
adjacent nerves. Which of the following symptoms is LEAST likely to result?
A.
B.
C.
D.
E.
Weakness of the sternohyoid muscle
Loss of sensation above the vocal cords
Paralysis of the cricothyroid muscle
Hoarseness
Loss of sensation of the skin just anterior to the auricle
An oral surgeon, while correcting an uneven temporomandibular joint, is especially careful to
avoid damage to the auriculotemporal nerve. He is aware that this nerve
A.
B.
C.
D.
E.
supplies the temporalis muscle.
travels with the occipital artery.
is a branch of the maxillary nerve.
has roots which surround the inferior alveolar artery.
carries parasympathetic fibers to the parotid gland.
In preparation for a thyroidectomy, a resident recalls that all of the following statements about
the superior thyroid artery are correct EXCEPT that it
A.
B.
C.
D.
E.
is a branch of the external carotid artery.
travels with the recurrent laryngeal nerve for part of its course.
has anastomoses with the opposite superior thyroid artery at the isthmus.
could receive blood from the inferior thyroid artery following occlusion of the common
carotid artery.
gives off a superior laryngeal branch.
17
62.
*
63.
While preparing for surgery in the infratemporal fossa, you remind yourself that the chorda
tympani nerve
A.
B.
C.
D.
E.
has fibers that synapse in the otic ganglion.
is a branch of the glossopharyngeal nerve.
carries taste fibers to the lingual nerve.
exits the cranial cavity through the stylomastoid foramen.
travels for part of its course in the middle cranial fossa.
During resection of the trigeminal ganglion for relief from trigeminal neuralgia the motor root of
the trigeminal nerve was accidently lesioned. A muscle expected to be paralyzed is the
*
A.
B.
C.
D.
E.
sternohyoid.
stapedius.
tensor tympani.
posterior belly of the diagastric.
buccinator.
64.
The otic vesicle develops into all the following structures EXCEPT the
*
A.
B.
C.
D.
E.
cochlear ducts.
semicircular canals.
endolymphatic sac.
utricle.
tubotympanic recess.
18
65.
*
Select the lettered part of the figure below that best indicates the structure that gives rise to the
external auditory meatus.
A.
B.
C.
D.
E.
A
B
C
D
E
19