neuroanatomy 3rd Comprehensive Examination 98 - 120 Flashcards
neuroanatomy 3rd Comprehensive Examination 98 - 150
Questions 98-102
Match the descriptions in items 98-102 with the appropriate lettered lesion {shaded area) in the
diagram of a cross-section of the spinal cord
- Ipsilateral leg dystaxia
98-B. Interruption of the dorsal spinocerebellar tract results in ipsilateral leg dystaxia (i.e., in-
coordination). The cerebellum is deprived of its muscle spindle input from the lower extremity.
Questions 98-102
Match the descriptions in items 98-102 with the appropriate lettered lesion {shaded area) in the
diagram of a cross-section of the spinal cord
- Ipsilateral flaccid paralysis
99-D. Destruction of ventral horn cells (lower motor neurons; LMNs) results in an ipsilateral flaccid paralysis (an LMN lesion), with muscle atrophy and loss of muscle stretch reflexes (are- flexia).
Questions 98-102
Match the descriptions in items 98-102 with the appropriate lettered lesion {shaded area) in the
diagram of a cross-section of the spinal cord
- Contralateral loss of pain and tempera-
ture sensation one segment below the lesion
100-E. Interruption of the lateral spinothalamic tract results in a contralateral loss of pain and
temperature sensation one segment below the lesion. The decussation occurs in the ventral white
commissure in the spinal cord.
Questions 98-102
Match the descriptions in items 98-102 with the appropriate lettered lesion {shaded area) in the
diagram of a cross-section of the spinal cord
- Exaggerated muscle stretch reflexes
(MSRs) below the lesion
101-C. Interruption of the lateral corticospinal tract results in an ipsilateral upper motor neu-
ron (UMN) lesion, which is characterized by exaggerated muscle stretch reflexes (hyperreflexia),
spastic paresis, muscle weakness, a loss or diminution of superficial reflexes (i.e., abdominal and
cremaster reflexes), and the Babinski sign. The deficits are below the lesion on the same side.
The lateral corticospinal tract decussates in the caudal medulla
Questions 98-102
Match the descriptions in items 98-102 with the appropriate lettered lesion {shaded area) in the
diagram of a cross-section of the spinal cord.
- Loss of two-point tactile discrimination
in tne ^^lateral foot
102-A. A lesion of the gracile fasciculus results in a loss of two-point tactile discrimination in
the ipsilateral foot. The dorsal column-medial lemniscus pathway decussates in the caudal
medulla.
Questions 103-108
Match the descriptions in items 103-108 with
the appropriate lettered lesion (shaded area)
shown on one of the two cross-sections of the
brainstem.
- Medial rectus palsy on attempted lateral gaze
103-C. This lesion includes the two medial longitudinal fasciculi (MLFs). The patient has MLF
syndrome and will have a medial rectus palsy on attempted lateral gaze to either side. Conver-
gence remains intact.
Questions 103-108
Match the descriptions in items 103-108 with
the appropriate lettered lesion (shaded area)
shown on one of the two cross-sections of the
brainstem.
- Lateral rectus paralysis; contralateral spastic hemiparesis
104-E. This lesion includes three major structures: the medial lemniscus, corticospinal fibers,
and exiting abducent root fibers (CN VI) traversing the corticospinal fibers. Interruption of the
abducent fibers causes an ipsilateral lateral rectus paralysis with medial strabismus. Damage
to the uncrossed corticospinal fibers results in contralateral spastic hemiparesis.
Questions 103-108
Match the descriptions in items 103-108 with
the appropriate lettered lesion (shaded area)
shown on one of the two cross-sections of the
brainstem.
- Occlusion of the posterior inferiorcerebellar artery
105-A. Occlusion of the posterior inferior cerebellar artery (PICA) infarcts the lateral zone of
the medulla, causing PICA syndrome. The major structures involved are the inferior cerebellar
peduncle, spinal trigeminal tract and nucleus, spinal lemniscus, the nucleus ambiguus, and ex-
iting vagal fibers of CN X.
Questions 103-108
Match the descriptions in items 103-108 with
the appropriate lettered lesion (shaded area)
shown on one of the two cross-sections of the
brainstem.
- Loss of the corneal reflex ; contralateral loss of pain and temperature sensation from the body and ectremities
106-D. This lesion includes the facial motor nucleus of CN VII and its intra-axial fibers, thus
accounting for the loss of the corneal reflex (efferent limb). The spinal trigeminal tract and nu-
cleus and the spinal lemniscus also are damaged by this lesion. Damage to the spinal trigeminal
tract and nucleus causes an ipsilateral facial anesthesia, including loss of the corneal reflex (af-
ferent limb). Damage to the spinal lemniscus (lateral spinothalamic tract) causes a contralateral
loss of pain and temperature sensation from the body and extremities.
Questions 103-108
Match the descriptions in items 103-108 with
the appropriate lettered lesion (shaded area)
shown on one of the two cross-sections of the
brainstem.
- Hemiatrophy of the tongue ; contralateral hemiparesis ; contralateral loss of vibration sensation
107-B. This lesion damages the hypoglossal nucleus of CN X and exiting root fibers, the medial
lemniscus, and the corticospinal tract. Damage to the hypoglossal nerve results in an ipsilateral
flaccid paralysis of the tongue, an LMN lesion. Damage to the medial lemniscus results in a con-
tralateral loss of tactile discrimination and vibration sensation. Damage to the corticospinal
(pyramid) tracts results in a contralateral spastic hemiparesis. This symptom complex is known
as medial medullary syndrome.
Questions 103-108
Match the descriptions in items 103-108 with
the appropriate lettered lesion (shaded area)
shown on one of the two cross-sections of the
brainstem.
- hoarseness ; horner syndrome ; singultus
108-A. Lateral medullary syndrome [posterior inferior cerebellar artery (PICA) syndrome] usu-
ally includes hoarseness, Horner syndrome, and singultus (hiccups). Damage to the nucleus am-
biguus causes a flaccid paralysis of the muscle of the larynx with hoarseness (dysphonia and
dysarthria). Interruption of descending autonomic fibers to the ciliospinal center at Tl causes
sympathetic paralysis of the eye (Horner syndrome). The anatomic causes of singultus are not
clear.
Questions 109-114
The response options for items 109-114 are the
same. You will be required to select one answer
for each item in the set.
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial (VPM) nucleus
(E) Mediodorsal nucleus
Match each of the following descriptions with
the appropriate nucleus.
- Receives input from the dentate nucleus
109-C. The ventral lateral nucleus receives input from the dentate nucleus of the cerebellum
and projects to the motor cortex (area 4). The ventral posterolateral (VPL) nucleus also receives
input from the dentate nucleus and projects to the motor cortex.
Questions 109-114
The response options for items 109-114 are the
same. You will be required to select one answer
for each item in the set.
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial (VPM) nucleus
(E) Mediodorsal nucleus
Match each of the following descriptions with
the appropriate nucleus
- Receives input of taste sensation from the
solitary nucleus
110-D. The ventral posteromedial (VPM) nucleus receives input of taste sensation from the soli-
tary nucleus of the medulla and pons, and projects this input to the gustatory cortex of the pari-
etal operculum (area 43).
Questions 109-114
The response options for items 109-114 are the
same. You will be required to select one answer
for each item in the set.
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial (VPM) nucleus
(E) Mediodorsal nucleus
Match each of the following descriptions with
the appropriate nucleus.
- Receives input of pain and temperature
sensation from the face
111-D. The ventral posteromedial (VPM) nucleus receives general somatic afferent (GSA) input
from the face, including pain and temperature sensation. It also receives special visceral affer-
ent (SVA; taste sensation) input from the tongue and epiglottis.
The response options for items 109-114 are the
same. You will be required to select one answer
for each item in the set.
(A) Anterior thalamic nucleus
(B) Centromedian nucleus
(C) Ventral lateral nucleus
(D) Ventral posteromedial (VPM) nucleus
(E) Mediodorsal nucleus
Match each of the following descriptions with
the appropriate nucleus.
- Receives the mamillothalamic tract
112-A. The anterior thalamic nucleus receives input from the mamillary nucleus via the mamil-
lothalamic tract and direct input from the hippocampal formation via the fornix. The anterior
nucleus projects, via the anterior limb of the internal capsule, to the cingulate gyrus (areas 23,
24, and 32).
