Cerebral cortical function Flashcards
What is the Categorical hemisphere?
hemisphere for sequential-analytic processes, in humans this is the language hemisphere, usually left hemisphere
What is the representational hemisphere?
hemisphere for visuospatial relations (the nondominant hemisphere for language), usually right hemisphere
What are the brodmann areas for the posterior parietal cortex?
5 and 7
What are the inputs and outputs of the posterior parietal cortex?
a. Interconnected with sensory and motor cortices.
b. Sends information to cerebellum via pontine nuclei.
What determines which hemisphere is dominant?
Where language center is
Contralateral neglect is often seen with what type of lesions?
Hemispheric lesions
What is personal neglect syndrome?
Deficit in self image of one side of the body
Denial of half of the body is a part of them = ?
Verbal asomatognosia
What is the function of the posterior parietal cortex?
Goal directed movements
True or false: There are separate pathways to the premotor cortex from visual cortex via parietal lobe to control reaching for an object and grasping the object.
True
Damage to what part of the brain produces neglect syndrome? Why?
Posterior parietal lobe–has attention sensitive neurons
What is spatial neglect?
- sensory neglect of extra personal space on one side
* problem copying left side of drawing
What is representational neglect?
Neglect of one half of a remembered image
What is asomatognosia?
when patient has lack of awareness of the condition of all or part of his body
What is verbal asomatognosia?
when patient verbally denies for example that his arm belongs to him
What is Astereognosis?
inability to identify objects by feeling them
What can cause astereognosis?
lesions in somatosensory cortices in parietal lobe
What is agnosia?
general term for the inability to recognize objects by a particular sensory modality even though sensory modality itself is intact.
What part of the left hemisphere is larger than the right?
Planum temporal
What is the cortical area for stereognosis?
Secondary somatosensory
What is the cortical area affected in visual agnosia?
Secondary visual
What is the cortical area affected in auditory agnosia?
Secondary auditory
What is the Wada test?
inject short acting barbiturate (e.g. Amobarbital) into internal carotid artery and look for transient aphasia
True or false: the planum temporale is the same size on both sides in infants, since they have no learned language yet
False–born with it larger
What is the non-dominant hemisphere responsible for?
spatial abilities, the comprehension of complicated patterns
Control of affective components of language
What part of language does the left hemisphere handle?
lexical and syntatic
What part of language does the right hemisphere handle?
Emotional coloring of languages
What are the BA numbers for Broca’s area?
45 and 44
What are the BA numbers for Wernicke’s area?
22
What are the fibers that connect Broca’s and Wernicke’s areas?
Arcuate fasciculus
What causes Broca’s aphasia?
lesions in Brodmann areas 44 and 45 in milder Broca’s area aphasia or deeper in true Broca’s
Nonfluent aphasia = ?
Broca’s aphasia
What are the symptoms of Broca’s aphasia?
Patient has limited speech but it is slow and labored with nonessential words omitted (telegraphic speech)
Can Broca’s aphasia pts comprehend words?
Only single words and grammatically simple sentences.
Can Broca’s pts repeat words said to them?
No
True or false: Broca’s pts area aware of their deficits
True
What causes Wernicke’s aphasia?
Lesions in Brodmann area 22 in the posterior temporal gyrus
What are the symptoms of Wernicke’s aphasia?
cannot understand either spoken or written language but they display fluent paraphasic speech. Speech sometimes called word salad
What is paraphasis? What syndrome is this seen in?
patient may use an incorrect but similar sounding word.
Seen in Wernicke’s
Are pts with Wernicke’s aphasia aware of their condition?
Somewhat
What is conduction aphasia? What causes it?
interruption of the connections between Broca’s and Wernicke’s areas. Damage is to complex connection system not just the arcuate fasciculus.
What are the symptoms of conduction aphasia? (2)
- Comprehension can be normal for simple sentences and speech is fluent but patient uses many paraphasias.
- Ability to repeat what is heard is lost.
What are the symptoms of global aphasia?
Patients cannot produce understandable speech or comprehend spoken language or written language
True or false: global aphasia pts cannot produce any words
False–May still have “automatic” speech such as stock expletives, and reciting days of the week or counting. Some patients can sing previously learned songs including melody and lyrics
What is alexia?
a disruption in the ability to read
True or false: Patient can have pure alexia without aphasia
True
What causes Alexia?
Probably caused by a disconnection between the visual and language systems
What causes agraphia?
May be combined with alexia but these disorders can appear separately from each other and from aphasia.
American sign language depends on which hemisphere?
Left
Which aphasia has disordered syntax, grammar and structure of individual words?
Broca’s
Which aphasia has a tendency to perseverate?
Broca’s
Which aphasia has Halting speech? FLuent?
Halting = Brocas Fluent = Wernicke's
What is productive aphasia?
Broca’s aphasia
Expressing and recognizing emotion in speech is associated with which hemisphere?
Right
What is aprosodia? Which hemisphere is lesioned to produce this?
loss of emotional expression in their speech. –right
Patients with right hemisphere lesions can have aprosodia. What are the symptoms of this? (2)
a. patient’s own speech might show inappropriate intonation.
b. patient has problems interpreting the emotional tone of others speech.
Patients with right hemisphere lesions can have difficulty comprehending meaning when?
when full understanding requires relationships among sentences rather than each sentence understood in isolation
What are the symptoms with dorsolateral prefrontal area damage?
Patients have trouble with executive functions; planning, choosing goals, monitoring the execution of a plan.
What are the symptoms with orbitofrontal area damage?
Patients have disinhibition; they ignore social conventions, are impulsive and unconcerned about consequences.
What are the symptoms with medial frontal (anterior cingulate) area damage?
Patients display apathy and slowing of cognition. This apathy can cause abulia or even akinetic mutism.
What is abulla?
the loss or impairment of the ability to perform voluntary actions and make decisions
What is Akinetic mutism?
patient does not move or speak even though they are awake.
What are the symptoms of prefrontal syndrome?
Loss of responsibility
Planning deficits
Perseveration
What are frontal release signs?
release of “primitive” reflexes examples-suckling reflex, grasp reflex
