Section 9 - Diencephalon and Telencephalon Flashcards
Irritative cortical lesions of the frontal eye field make the eyes look ______ the side of lesion.
Destructive cortical lesions of the frontal eye field make the eyes look ______ the side of the lesion.
- Away from
- Toward
Lesions to Brodmann area 44,45 (pars opercularis and pars triangularis) produce…
Broca (or expressive) aphasia - difficulty translating thoughts into coherent sentences.
Lesions to Brodmann area 22,21 (temporal lobe) produce…
Wernicke (receptive) aphasia - patients cannot understand what they hear, cannot read or write, and speak in a jumble of words that makes no sense
Thalamic syndrome is caused by:
Disturbance of thalamic somatosensory portion (from a vascular lesion), involving ventral posterior thalamus.
List symptoms of thalamic syndrome.
- Proprioception, pain, temp, touch impaired on CONTRALATERAL side on body
- Pain can be spontaneious, intractable to analgesics
- May be an emotional liability - spontaneous laughing/crying
What is amusia?
Aphasia form in which there is an inability to produce/recognize music
Damage to basilar nuclei results in…
motor deficits (like involuntary movements)
What is auditory agnosia?
Inability to recognize or respond to complex sounds
Central pain is theorized to arise from __________
abnormal activity in thalamic or cortical neurons deprived from normal afferent
What is Korsakoff’s syndrome?
Amnesia due to degenerative changes in areas surrounding the third ventricle
- Mediodorsal thalamic nucleus
- Mamillothalamic tract/mammillary bodies
What is hemiballismus?
Involuntary movements that come on suddenly with great force and rapidity from lesion in CONTRALATERAL subthalamic nucleus. Movements are flailing aimlessly, spontaneous, most severe at proximal joints of limbs (esp. arms). Can involve face mm.
Vascular lesions of ______ can cause hemiballismus.
posteromedial branch of PCA or posterior communicating artery
What is quatrinopias?
Lesion of the retrolenticular limb of internal capusle. A contralateral quadrant of each eye is lost. (Vision is lost I’m assuming…not a quarter of the actual eyeball).
What is a craniopharyngioma?
Rathke pouch tumor - pouch fails to undergo migration and apposition to infundibulum. Tumor mimics pituitary gland –> visual problems, diabetes insipidus, increased intracranial pressure
A lesion of the thalamic ventromedial nucleus produces what (bilateral)?
Hyperphagia –> obesity (generally, over-eating)
A pinealoma causes what?
Depressed gonadal function, delayed puberty.
A lesion of the pinal causes what?
Precocious puberty (pineal secretions inhibit gonadal formation)
What is anterior choroidal artery syndrome?
ACA is occluded –> visual and motor deficits reflecting damage to optic tract and inferior portion of posterior limb of internal capsule
Vascular lesions of the thalamus can extend into the internal capsule (and vice versa). Strokes in hemisphere can lead to ________
Contralateral hemiparesis and hemianesthesia (corticospinal and thalamocortical fibers)
What is Dejerine-Roussy syndrome?
Intense pain following occlusion (such as in thalamogeniculate a.) and subsequent ischemia to the corticospinal/thalamocortical fibers of internal capsule.
(ischemia here causes contralateral hemiparesis and hemianesthesia)
What does an insular cortex lesion cause?
Results in diminution or loss of desire to continue addictive behavior.
Lesion of the primary visual cortex can cause _______, which is _______.
- Homonymous hemianopia
- Loss of visual input from contralateral half of visual field of each eye (designated right or left hemianopia)
Seizure therapy for patients with severe generalized seizures is done by _________
Disconnecting 75% of the corpus callosum (mostly leave splenium).
Lesions of the corpus callosum can be caused by:
- Vascular infarct
- Tumor
- Necrosis
- Demyelination
