Cognitive neuroanatomy Flashcards
Broca’s area is in the _____ of the ________
Broca’s area is in the opercular and triangular portions of the of the inferior frontal gyrus
Wernicke’s area is in the ______________
Wernicke’s area is in the superior temporal gyrus
This area of the parietal lobe is important for allowing visual information from reading that has been processed by the visual association cortex into the temporal lobe for language processing
Angular gyrus
In Broca’s aphasia, ______ is impaired but _____ is intact
In Broca’s aphasia, repetition is impaired but comprehension is intact .
(Broca’s disconnects from Wernicke’s area, so repetition is impared)
Broca’s aphasia is caused by an infarct in the ______ division of the MCA, while Wernecke’s is caused by an infarct in the ______ division of the MCA
Broca’s aphasia is caused by an infarct in the SUPERIOR division of the MCA, while Wernecke’s is caused by an infarct in the INFERIOR division of the MCA
Describe which aphasias have intact repetition and which do not, and localize them
- All have impaired naming except for pure anomia (which can localize to multiple spots).
- Broca and Wernicke have impaired repetition
- Transcortical sensory and motor have intact repetition
Describe conduction aphasia
Fluent with intact comprehension but impaired repetition (the BLOCK or deficit is in conduction)
Transcortical Sensory Aphasia
fluent, impaired comprehension but intact repetition (like Wernecke but able to repeat)
Transcortical motor aphasia
NON-fluent, intact comprehension and repetition (like Broca but with intact comprehension)
Transcortical SENSORY aphasia can be caused by
MCA-PCA watershed infarcts
fluent, impaired comprehension but intact repetition (like Wernecke but able to repeat)
Transcortical Sensory Aphasia
NON-fluent, intact comprehension and repetition (like Broca but with intact comprehension)
Transcortical motor aphasia
Transcortical MOTOR aphasia can be caused by
ACA-MCA watershed infarct
What is a mixed transcortical aphasia and what is a common cause
- impaired comprehension
- impaired fluency
- INTACT repetition
- caused by combined MCA and PCA infarcts (like a combo of transcortical motor and sensory aphasias)
What deficits do you expect from this lesion?
Alexia WITHOUT agraphia. Lesion in the DOMINANT occipital lobe that involves the corpus callosum, often from PCA infarct
- You can’t see the RIGHT (contralateral) visual field to read
- You can see the LEFT (ipsi) visual field, but you can’t get the information to the LEFT/dominant (language processing) hemisphere b/c your posterior CC is out
Localize alexia WITHOUT agraphia and common etiology
Lesion in the DOMINANT occipital lobe that involves the corpus callosum, often from PCA infarct
- You can’t see the RIGHT (contralateral) visual field to read
- You can see the LEFT (ipsi) visual field, but you can’t get the information to the LEFT/dominant (language processing) hemisphere b/c your posterior CC is out
Name the 4 deficits in Gerstmann’s Syndrome
- Agraphia
- Acalculia
- Left/right disorientation
- Finger agnosia
Localize the following combination of deficits and identify the syndrome:
- Agraphia
- Acalculia
- Left/right disorientation
- Finger agnosia
Gerstmann’s Syndrome
Localizes to the dominant inferior parietal lobule in region of angular gyrus
Often accompanied by other deficits localizing to inferior parietal lobule, including alexia, contralateral visual field cut, and anomia or worse aphasia
Define and localize aphemia
Def: severe speech apraxia without a language disturbance. Written language, comprehension are intact
Localization: dominant frontal operculum restricted to broca’s area
A patient can hear but cannot understand any words. Speech is fluent, and reading and writing are INTACT. Identify the syndrome and localize it
Pure word deafness
Infarct in auditory area of DOMINANT hemishere extending to subcortical white matter –> cuts off auditory input from contralateral hemisphere
You hear, but you cannot PROCESS the language components b/c you can’t get it out of primary auditory cortex (sort of like alexia without agraphia)
How is the amygdala connected with the frontal lobes?
Amygdala is connected with orbital and medial frontal lobes by uncinate fasciculus
How are frontal lobes connected to hippoampus
Via cingulate gyrus and parahippocampal gyrus
Which thalamic nucleus is most interconnected with prefrontal cortex?
mediodorsal nucleus
The prefrontal cortex connects to the basal ganglia mainly via ______
The prefrontal cortex connects to the basal ganglia mainly via the HEAD of the caudate nucleus
Describe the difference between the dorsal and ventral streams
Dorsal stream answers “where” questions
Ventral stream answers “what” questions; specific areas for identifying faces, colors, letters
Localize prosopagnosia
Fusiform gyrus (inferior occipitotemporal lobe)
What symptoms might you see with lesions in the inferior occipitotemporal cortex?
- Prosopagnosia
- Achromotopsia (cortical color blindness)
- may also see alexia, upper quadrant or b/l upper visual field cut if you hit the inferior bank of the calcarine sulcus
What is the difference between achromotopsia and color agnosia?
achromotopsia is cortial color blindness, caused by injury to fusiform gyrus (can’t process color)
color agnosia is a disconnect syndrome caused by injury in dominant occipital cortex involving corpus callosum. Associated with alexia WITHOUT agraphia and right hemianopia. Can’t name colors pointed to visually but perception is intact (can match colors presented visually and name a color when it is described. see figure)
Identify and localize this triad of symptoms
- simultagnosia
- optic ataxia
- ocular apraxia
Balint’s syndrome
Localizes to BILATERAL dorsolateral parieto-occipital association cortex (WHERE visual stream)
Balint’s syndrome
What are the symptoms and the localization?
Localizes to BILATERAL dorsolateral parieto-occipital association cortex (WHERE visual stream)
- simultagnosia
- optic ataxia
- ocular apraxia
What is a common cause of Balint Syndrome?
Bilateral MCA-PCA watershed infarcts (you have to take out the parieto-occipital association cortices bilaterally)
What are some symptoms you might expect to see associated with Balint’s syndrome?
- inferior quadrant visual field cuts
- (parietal optic radiations)
- aphasia
- (Receptive > expressive)
- hemineglect
- (R parietal)
