Higher Cortical Function & Language Flashcards
In general, what are the functions of the parietal lobe, temporal lobe and frontal lobe?
Parietal-attend to external stimuli
Temporal- identify the type of stimuli
Frontal lobe- attend to and plan appropriate behavior
Global organization of association areas have _________ more anterior and _________more posterior.
Anterior- planning control and regulation
Posterior- sensory/association functions
The left hemisphere is most important for what part of speech?
The right hemisphere is important for what part of speech?
Left- comprehension and production of speech
Right- prosody (rhythm and intonation)
Broca’s area correnates to what aspect of speech?
motor/action
Wernicke’s area correlates to what aspect of speech?
comprehension and association
What lobe is Broca’s area found in?
What motor humunculus structure is it adjacent to?
What Brodmann area does it correlate with?
It lies in the inferior frontal lobe in front of the premotor cortex.
It is adjacent to the facial-oropharyngeal representation on the homunculus
It correlates to Brodmann 44,45
What is the frontal operculum?
The area of cortex that overlies the insula
What are the three major functions of Broca’s area?
- Production of Speech
- Ordering and grouping sound
- Matching output to target sound
What lobe is Wernicke’s area located in?
What Brodmann area does it correlate with?
What gyrus is it adjacent to?
Temporal lobe
22
adjacent to the primary auditory cortex
What are the two major functions of Wernicke’s area?
- memory of the sounds of words
2. provides a target of what sounds should be and constrains brocas area
What would a lesion to Wernicke’s area produce?
Lack of comprehension because the sound of the word cannot be mapped to a meaning
What is the arcuate fasciculus?
the white matter tract that connects Wernicke’s and Brocas areas
What is an aphasia?
What is the most common cause?
a break down or disruption of speech or verbal comprehension
Cause: stroke, tumor, trauma infection, nutrition that affect a speech cortical area
What is it important to distinguish an aphasia from?
A hearing problem
non-broca area deficiencies
What are the 4 characteristics of an aphasia?
- Comprehension
- Repetition
- Confrontrational naming
- Fluency
What is comprehension?
How is it assessed?
A lesion to what area disrupts it?
the ability to understand spoken language.
through conversation
posterior cortical areas (Wernickes)
What is repetition?
What does it help diagnose?
What lesion affects it?
the ability to repeat words regardless of comprehension
helps diagnose degenerative diseases
a lesion to the perisylvian area (Broca, arcuate fasciculus, wernickes)
What is fluency?
An aphasia where a patient is still fluent must have occured in what area?
Fluency is the rate and rhythm of word utterances.
If patient has a lesion, but is still fluent it must have occured in the posterior area because brocas area must be intact for fluent speech.
A person comes in speaking at an appropriate rate and rhythm but they are speaking in gibberish. Where is their lesion? Are they fluent?
Yes they are fluent so their lesion is probably posterior (Wernickes or arcuate fasciculus)
What does the NIH stroke scale Q9 assess?
What are the ways you asses it?
Best language. 0- no aphasia 1- mild to moderate 2- severe 3- mute/ global aphasia
Assessed by descriptions of complicated pictures, sentence repeating
If there is a Broca’s aphasia, what happens to:
- speech output (fluency)
- Repitition
- Comprehension’
- Localization
- non-fluent speech- slow halting rhythm, reduced phrase length, agrammatic speech (mostly nouns)
- no repetition
- Intact comprehension
- inferior frontal lobe lesion
With a Broca’s area aphasia, is the patient aware of their deficit?
Yes, so it is very frustrating for them and they work well with speech therapists
What is anomia?1
the inability to “find a word”
“four legs, says meow”: instead of cat
Why might Broca’s area have limited comprehension for long grammatically complex sentences?
because there may be damage to the phonological loop (ability to repeat) which interferes with working memory
When there is a Wernicke’s aphasia, what is the :
- localization
- fluency/speech output
- Repetition
- Comprehension
- Temporal lobe in Brodmann 22
- fluent with increased speech rate and rhythm, phrase length is normal, words are mispronounced, misused and are nonsensical
- repetition is impaired because they cant match the word sounds to what you ask them to repeat
- no comprehension because they cant correlate the sounds to meaning
Are people with Wernicke’s aphasias aware of their deficits?
No- they are not aware they are speaking in gibberish and are often classified as psychotic because they act like nothing is wrong
What is a conduction aphasia?
an aphasia where the arcuate fasciculus is lesioned. This person can comprehend what you are saying and can speak fluently because Wernickes and Brocas are intact but they speak gibberish because the comprehension area and fluency area are not matching up.
Repetitition is still impaired.
They are aware of their deficit and it is very frustrating
What is the only recorded aphasia where repetition is intact?
Transcortical aphasia
What are the right hemisphere cortical functions?
visuospatial and spatially-directed attention
What lobes of the brain contribute to intact visuospatial function and perception?
All of them
What are the presentations of patients with visuospatial and perceptual difficulties?
neglect (usually of the left side)
agnosia (take info in but dont process it)
What lobe of the brain is associated with spatially-directed attention?
Parietal and association cortex that is adjacent to the visual areas in the occipital lobe
If there is a lesion in the right temporal lobe, what will happen to visuospatial perception?
If there is a left sided lesion, what will happen to visuospatial perception?
Right sided lesion = left side neglect
Left sided lesion = no problem
What is the definition of hemi-spatial attentional neglect?
the failure to respond to the side opposite the brain lesion where the failure is not due to motor or sensory deficits
How do you test clinically for neglect?
- draw a picture
- line cancelling
- line bissection
What is a critical brain area for association?
the confluence of the parietal, temporal and occipital lobes
What is the denial of an impairment?
anosoagnosia
What is the lack of concern about a neurological deficit?
anosodiaphoria
What is simultanagnosia?
When the person can perceive individual parts of the picture but are unable to appreciate the picture as a whole
What are the two major types of agnosia?
- apperceptive- familiar objects cant be identified because of reduced visibility
- Associative agnosia
What is semantic dementia and what lobe does it usually affect?
language difficulty assigning meaning to words. It affects mainly the left temporal lobe
What is agnosia? What other disorder is it most frequently associated with?
The ability to see an object but inability to recognize what it is. it is associated with semantic dementia.
What is prosopagnosia? What lobe is it associated with?
the inability to recognize faces. Right temporal lobe deficit
What is the difference in agnosia for right temporal lobe and left temporal lobe lesions?
Right- agnosia of faces and objects
Left- difficulty with language related stimuli
What is ocular apraxia?
difficulty initiating voluntary sacchades to visual target
What is optic ataxia?
Defect in head movement under visual guidance
What is apraxia?
a disorder of motor planning that impairs the ability to correctly perform skilled, purposeful movement
Apraxia can only be diagnosed if what other ailments are ruled out?
- comprehension
- weakness
- sensory loss
- movement disorder
What area of the brain needs to be active for activities depending on congitive information, working memory and planning and sequence of movment?
prefrontal cortex
What brain lobe allos us to use stored info to guide the SEQUENCE of behavior?
frontal lobe
What brain hemisphere allows us to represent motor programs that specify spatial and temporal characteristics of an action?
the left hemisphere
What lobe houses praxicons (memories of skilled movements)?
the left temporal lobe
What is the supplementary motor area?
part of the motor cortex that translates spatial-temporal motor planning in the left parietal lobe into motor programs which activate the primary motor cortex
What transfers information from the left SMA to the right SMA?
anterior corpus callosum
What is ideomotor apraxia?
What are three typical errors seen?
the person has trouble pretending to perform a skilled movment
- spatial errors
- body parts used as tool substitutions
- timing and sequence of movements are wrong
When are ideomotor apraxia the most dramatic?
- In the asbsence of an actual tool
2. when the action is not demonstrated by the examiner
Where can lesions be found in a person with ideomotor apraxia?`
- corpus callosum- right motor cortex doesnt receive input from the left SMA
- Posterior left hemisphere where the praxicons are located
- supplemental motor area- movement memory cannot translate to action
What is an ideational apraxia?
The person has trouble sequencing the parts of an action like mailing a letter or making a sandwich
What is the usual cause for an ideational apraxia?
dementia or vascular disease affecting the frontal lobe
Stroke in what artery disrupts the anterior corpus callosum?
anterior cerebral artery
What is a conceptual apraxia?
the patient has impaired conceptual knowledge about how to use a particular tool. recognize toothbrush, dont know how to use it
What disorder is conceptual apraxia related to?
Alzheimers disease
what is the difference between a transitive and intransitive limb gesture?
Which is usually affected first in a neurodegenerative disorder?
Transitive limb gestures are performing a specific action that require a tool (pretend to brush teeth, unlock door, etc)
Intransitive are genstures that do not require a tool like waving hello)
Transitive are affected first
