chapter 2: neuropathology of aphasia Flashcards
classical/ traditional view of neuropathology of aphasia
discrete areas of the brain within the zone of language perform different functions and are connected to form a network resulting in comprehension and production
Supported by direct observation and indirect observation of the brain
classical/ traditional view of neuropathology of aphasia
opposing view of neuropathology of aphasia
Language is supported by an intensely interactive set of neural networks widely disrupted throughout the brain and that aphasia is the consequence of disruption within this set of networks; no language areas
Justified by different brains light up differently in scanners when challenged with language tests; lesions in different parts of the brain may result in similar clinical syndromes
opposing view of neuropathology of aphasia
T/F: The characteristics of aphasia in any individual are dynamic and typically evolve over time; thus, a specific person’s needs depend on current deficits, and not necessarily on the anatomic locus of the lesion
True
T/F: Cerebral Dominance: one hemisphere contains the neural structures responsible for language and the other hemisphere does not contribute to language
False
T/F: Dominant hemisphere contains more of whatever is important for language and the other hemisphere contains less
True
Both hemispheres contribute in ______ degrees with different components of language function
varying
__% of right-handers have left-hemispheric dominance for language
95
__% of left-handers may have left-hemispheric dominance for language and __% may have bilateral dominance
70; 30
The right hemisphere contributes to many of the ______, _____, and ____ aspects of language in right-handers
prosodic, rhythmic, and pragmatic
T/F: The right hemisphere contributes to many of the prosodic, rhythmic, and pragmatic aspects of language
true
__% of aphasia syndromes conform roughly to the anatomo-clinical scheme; __% may be explained by individual difference in brain structure and other factors
80; 20
lesion location: lateral frontal, suprasylvian pre-Rolandic, extending into adjacent subcortical periventricular white matter
Broca’s aphasia
lesion location: Posterior third of superior temporal gyrus
Wernicke’s aphasia
lesion location: Supramarginal gyrus and underlying white-matter pathways (arcuate fasciculus); Wernicke’s area; left insula and auditory cortex
Conduction aphasia
lesion location: Angular gyrus; second temporal gyrus
Anomic aphasia
lesion location: Anterior frontal paramedian; anterior and superior to Broca’s area
Transcortical motor aphasia
lesion location: Posterior parieto-temporal, sparing Wernicke’s area
Transcortical sensory aphasia
lesion location: Large perisylvian, extending deep into sub adjacent white matter
Global aphasia
lesion location: Thalamus
Head of caudate nucleus, putamen, and/or internal capsule
subcortical aphasia
A lesion in this area would be in the territory of the superior division of the middle cerebral artery and often extends posteriorly to include the parietal lobe
Broca’s aphasia
produces mild dysprosody and mild agraphia with occasional word-finding and mild dysarthria
lesions in Broca’s area
do lesions in Broca’s area cause Broca’s aphasia
no
Lesions created through the distribution of the inferior division of the middle cerebral artery
Wernicke’s aphasia
which aphasia has at least two forms? and what are they?
Wernicke’s aphasia; 1) primarily temporal lesion & 2) extension of the lesion posteriorly
Wernicke’s Aphasia: primarily temporal lesion causes…
producing word-deaf variant in which reading may be relatively less affected
Wernicke’s Aphasia: extension of the lesion posteriorly…
visual connections will be disrupted; the patient will have more difficulty to understanding written language and language in context (less difficulty with isolated words)
afferent and efferent types of lesions occur in which aphasia?
conduction
Afferent
temporal lesions; repetition impaired because of defective memory
Efferent
parietal or insular lesions; result of problems with phonemic representation
T/F: any lesion in or near the zone of language can produce anomia. Virtually every aphasia has an anomic component
true
lesions in the angular gyrus produce what kind of aphasia
anomic
T/F: Other common forms of aphasia often evolve to a syndrome of primarily anomic aphasia in the process of recovery and these may present with widely varying lesion location
true
Anteriorly located lesion that interrupts the link between the supplementary motor cortex and Broca’s area but that spares Broca’s area causes what kind of Aphasia
Transcortical Motor
can lesions in transcortical motor aphasia be in more than one place?
yes
what are the possible locations of transcortical motor aphasia lesions
supplementary motor cortex, white-matter pathways, left frontal lobe
what are transcortical motor aphasia lesions caused by
disruption of blood flow either in the anterior cerebral artery or in the anterior-most penetrating branches of the middle cerebral artery
a common cause of transcortical motor aphasia
the infarction in the border-zone territory between the anterior and middle cerebral arteries
bilateral lesions occur in which aphasia
transcortical sensory
One of the forms of aphasia seen in Alzheimer’s disease, a disease with bilateral posterior association cortex neuropathology
transcortical sensory
Implication of severe language deficits across all language modalities
global aphasia
have precise clinicopathological correlates have not been defined yet for the subcortical aphasias
no
what is prominent in all forms of subcortical aphasia
preservation of repetition and disorders of attention
are disorders of oral language vs disorders of written language present in aphasia
yes!
Only written language effected
vascular in cause; lesion is usually in the distribution of the posterior cerebral artery
Exclusively oral effected
lesion is usually in the distribution of the middle cerebral artery
Both oral and written aspects of language effected
lesion in the distribution of the internal carotid artery
does the current theory in aphasia accept the notion of a one-to-one correspondence between specific linguistic structural elements and focal segments of the brain
no
A comprehensive neurological theory of language must take into account
evidence that most parts of the brain are engaged in the language act
In patients with aphasia, neuroimaging studies have tended to support the _______` view
classical
centers of language
represent critical crossroads for processing selected elements of language
a focal lesion in _____ could produce a predictable aphasic deficit
center of language
An integrative view of neurology of language
enhances our understanding of the phenomena of recovery from aphasia; lends itself to the development of theoretically motivated, brain-based approaches to aphasia therapy
