494-868 ( VI ) Flashcards
494-868 ( VI )
1. A lesion resulting in a nonfluent expres-sive aphasia would most likely be found in the (A) temporal lobe (B) parietal lobe (C) frontal lobe (D) occipital lobe (E) limbic lobe
l-C. A nonfluent, expressive motor aphasia (Broca’s aphasia) results from a lesion in the pos-terior inferior frontal gyrus (areas 44 and 45) of the dominant frontal lobe.
2. Broca's aphasia is frequently associated with (A) auditory hallucinations (B) finger agnosia (C) construction apraxia (D) an upper motor neuron (UMN) lesion (E) visual field deficits
D. Broca’s aphasia is frequently associated with an upper motor neuron (UMN) lesion of the
contralateral face and arm and occasionally of the leg. Broca’s speech area lies just anterior to
the motor strip; both Broca’s speech area and the motor strip are irrigated by the superior divi-sion of the middle cerebral artery (prerolandic and rolandic arteries). Broca’s aphasia is fre-quently associated with a “sympathetic apraxia,” an apraxia of the nonparalyzed left hand.
3. Alexia without agraphia and aphasia would most likely result from occlusion of the (A) left anterior cerebral artery (B) right anterior cerebral artery (C) left middle cerebral artery (D) left posterior cerebral artery (E) right posterior cerebral artery
D. Alexia without agraphia and aphasia results from occlusion of the left posterior cerebral
artery, which supplies the left visual cortex and callosal fibers (within the splenium) from the
right visual association cortex. Interruption of bilateral visual association fibers en route to the
left angular gyrus results in alexia. Because the angular gyrus and Wernicke’s area are
spared, the patient will not be agraphic or dysphasic
4. Agraphia and dyscalculia would most likely result from a lesion in the (A) left frontal lobe (B) left parietal lobe (C) right occipital lobe (D) left temporal lobe (E) splenium of corpus callosum
B. Lesions of the angular gyrus of the dominant hemisphere may result in Gerstmann’s
syndrome, which consists of agraphia, dyscalculia, finger agnosia, and left-right confusion.
- A patient is asked to bisect a horizontal
line through the middle and to draw the face
of a clock. The patient bisected the horizontal
line to the right of the midline and placed all
of the numerals of the clock on the right side.
The most likely lesion site for this deficit
would be in the
(A) left frontal lobe
(B) right parietal lobe
(C) left parietal lobe
(D) right temporal lobe
(E) left occipital lobe
B. The inability to draw a clock face or bisect a line through the middle is called construc-tion apraxia. Lesions of the right (nondominant) parietal lobe result in construction apraxia,
dressing apraxia, anosognosia, and sensory hemineglect
- A lesion of the dominant inferior parietal
lobule could result in all of the following
deficits EXCEPT
(A) the inability to perform calculations
(B) the inability to identify fingers
(C) the inability to write from dictation
(D) right-left disorientation
(E) difficulty in dressing
E. Dressing apraxia is a symptom of the nondominant parietal lobe. A lesion of the domi-nant angular gyrus is known as Gerstmann’s syndrome, which includes finger agnosia (auto-topagnosia or somatotopagnosia), right-left confusion, agraphia, and dyscalculia. Alexia may
be associated with Gerstmann’s syndrome.
- All of the following statements concerning
the parietal lobe are correct EXCEPT it
(A) contains the primary somatosensory area
(B) contains the angular gyrus
(C) contains the supramarginal gyrus
(D) contains the visual radiation
(E) contains Wernicke’s speech area
E. Wernicke’s speech area (included in Brodmann’s area 22 ) is found in the posterior part of
the superior temporal gyrus of the dominant hemisphere. Wernicke’s speech area includes the
planum temporale, which lies on the lower bank of the lateral sulcus.
- All of the following statements concerning
the layers of the neocortex are correct
EXCEPT
(A) layer III is the major source of corti-cothalamic fibers
(B) layer IV receives input from ventral pos-terolateral (VPL) and ventral posterome-dial (VPM) nuclei
(C) layer IV in the occipital lobe receives
input from the lateral geniculate body
(D) layer V contains the giant cells of Betz
(E) layer VI gives rise to cortical association
and callosal fibers
A. Layer VI is the major source of corticothalamic fibers. Layer IV is the major sensory-receiving station of the neocortex. Layer V gives rise to the corticospinal and corticobulbar
tracts and also contains the giant cells of Betz.
- Lesions of the frontal lobes may give rise
to all of the following EXCEPT
(A) ocular signs
(B) upper motor neuron (UMN) lesion signs
(C) gait apraxia
(D) hemianopias
(E) sucking, groping, and grasping reflexes
D. Frontal lobe lesions may affect the frontal eye field, the motor cortex, and the premotor
and prefrontal cortices (gait apraxia). Sucking, groping, and grasping reflexes are seen in
frontal lobe lesions. Hemianopias result from lesions of the visual pathway. The visual path-way is not found in the frontal lobe.
- All of the following statements concerning
the primary motor cortex are correct EXCEPT
(A) it is found in the paracentral lobule
(B) it is located in the frontal lobe
(C) it contains the giant cells of Betz
(D) it corresponds to Brodmann’s area 4
(E) ablation results in a permanent flaccid
paralysis
-E. The primary motor cortex, the motor strip (area 4), is located in the precentral gyrus
and in the anterior part of the paracentral lobule, both of which are found in the frontal lobe.
The giant motor cells of Betz are found in layer V of the motor cortex. Ablation of the motor
strip initially results in flaccid paralysis, which becomes a spastic contralateral hemiparesis
with Babinski’s sign.
- All of the following statements concern-ing the paracentral lobule are correct
EXCEPT
(A) it is found in two lobes of the brain
(B) it contains giant cells of Betz
(C) it is irrigated by two arteries
(D) its infarction results in loss of vibration
sense in the contralateral foot
(E) its infarction results in a contralateral
extensor plantar reflex
C. The paracentral lobule is perfused by the anterior cerebral artery; the territory of the
anterior cerebral artery extends a centimeter over the crest of the lateral convexity and per-fuses the hip area of the motor and sensory strips. The giant cells of Betz are largest in the
paracentral lobule.
