Neuro Exam 2.2
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Neuro Exam 2.2
neurology neuroscience neuroanatomy
review of neuro lecture 2 for exam 2
What are the specific functional cortical areas of the telencephalon?
primary motor cortex
primary sensory cortex
primary visual cortex
primary auditory cortex
What is another name for the primary motor cortex?
cerebral motor cortex
Where is the primary motor cortex located?
in pre-central gyrus of frontal lobe
in front of central sulcus
areas anterior to pre-central gyrus (association areas)
What is the central sulcus?
What does the primary motor cortex control?
voluntary skeletal muscle activity on contralateral side
The primary motor cortex is considered part what system?
What does the pryamidal system control?
voluntary skeletal muscle activity
What does the extrapyramidal system control?
involuntary skeletal muscle activity
The pre-central gyrus contains cell bodies of:
Upper motor nueon
How is the pre-central gyrus organized?
What does it mean for the pre-central gyrus to be somatotopically organized?
specific areas of the cortex control specific parts of the body (homunculus)
A large amount of the cortex is dedicated to:
smaller organs (more finesse mm)
Finesse control =
more neurons involved
ratio of lower motor neuron to number of extrafusal fibers being innervated
Contralateral v. ipsilateral:
depends on where lesion is on brain--some will be contralateral manifestations, others ipsilateral
What are other names for the primary sensory cortex?
primary somatosensory area
cerebral sensory cortex
Where is the primary sensory cortex located?
post-central gyrus (behind central sulcus) of the parietal lobe
What is the function of the primary sensory cortex?
allows discrimination and perception of and the location of general sensations
--need to know what the sensation is and where it is
General sensations are different to the 5 special senses, they are:
crude touch (rough, smooth, etc.)
fine tough (2 point discrimination)
proprioception (body position sense)
The left post-central gyrus controls what side of the body?
The right post-central gyrus controls what side of the body?
Does the post-central gyrus have the same somatotopic organization as the primary motor cortex?
If there is a lesion on a part of the post-central gyrus...
you will lose sensation and perception of the specific area on the contralateral side
More sensitive parts of your body have:
a larger portion of the cortex devoted to them
Damage to a part of the primary sensory cortex impacts:
discrimination and perception of and location of general sensations on the contralateral side of the body
If info doesn't reach the cortex:
then you are not consciously aware of sensation/environment
If the post-central gyrus is removed/damaged, can the patient perceive pain?
yes, from the thalamus
What is the reference point for contralateral v. ipsilateral in the primary sensory cortex?
Effect on opposite side of the lesion in primary sensory cortex is:
Effect on same side of the lesion in primary sensory cortex is:
Where must info go in order to be perceived?
Where is the primary visual cortex located?
occipital (posterior) lobe
adjacent to calcarine fissue
In Broadmann's terminology, the primary visual cortex is in which area?
How are images received in the brain?
What does the visual cortex do with the inverted images?
flips them right side up to make sense of them
(processess upside down, black and white image)
Visual info has to go where in order to perceive sight?
primary visual cortex
Damage to the primary visual cortex will cause what?
blindness (despite intact eyes, nerves, aqueous humor, etc.)
--Nothing is perceived until it reaches the cortex
Where is the primary auditory cortex?
superior temporal gyrus of temporal lobe
What is the function of the primary auditory cortex?
helps to perceive sound
Damage to the primary auditory cortex can cause:
deafness (if both sides are damaged)
Auditory info has to make it to the primary auditory cortex to:
make sense of what is being heard and allow you to hear
What are the primary cortical areas?
Intellectual, personality, psychic, abstract, self-control, cognition
motor speech cortex
Where are the intellectual, personality, psychic, abstract, self-control, cognition primary cortical areas?
anterior portion of frontal lobe
Intellectual personality, psychic, abstract, self-control, cognition primary cortical areas primarily occur in:
anterior 1/5 of frontal lobe
Is the frontal lobe important?
Injuries to the frontal lobe result in:
What part of a person does damage to the frontal lobe change?
personality changes completely
What does the olfactory cortex perceive?
The olfactory cortex involves 2 areas located where?
inferior temporal lobe
The olfactory cortex involves what 2 areas located in the inferior temporal lobe?
lateral olfactory area
medial olfactory area
What is another name for the lateral olfactory area?
Where is the lateral olfactory area?
passes lateral to the optic chiasm and terminates at the uncus
What is the uncus?
medial bulging in the parahippocampal gyrus
What is the most significant area in terms of conscious olfactory response?
lateral olfactory area
Lateral olfactory area:
smell, inferior temporal lobe
where smell perception is found
Where is the medial olfactory area?
medial to optic chiasm and under (in inferior temporal lobe
What does the medial olfactory area become?
anterior perforated substance
What does the gustatory cortex perceive?
How many locations of the brain are involved w/ taste (gustatory complex)?
What 3 locations of the brain are involved in the gustatory complex?
most ventral portion of post-central gyrus
Where is the insular cortex?
deep to lateral fissure
Where is the frontal operculum?
part of Broca's area
What is the function of the association areas?
refinement and interpretation
What are association areas?
areas of cortex surrounding (adjacent to) major cortical areas previously described and they refine and/or interpret major functions (auditory, visual, motor, primary somatosensory)
The associations areas helps visual cortex to:
see depth perception and other internal visual calculations (adds color, movement, 3D perception, etc. to primary vision)
Damage to the association area may cause:
loss of color, movement, depth perception, even though vision remains
Why is the association area important in therapy?
important to keep in mind w/ pt's w/ neurological insults (may have intact primary area, but lesion in association area)
A lesion in the association area will present w/:
What is the motor speech cortex?
allows a person to initiate speech by influencing portions of pre-central gyrus that control skeletal muscle for speech (larynx, pharynx, tongue, face, and mouth)
What is a major area of the motor speech cortex?
Where is the Broca's area located?
inferior frontal gyrus of frontal lobe
What does the Broca's area do?
acts like a computer that instructs portions of the pre-central gyrus to instigate speech
What is the Broca's area?
primary cortex for motor speech
association area of pre-central gyrus that finesses function
What Broadmann's classification areas is the Broca's area?
areas 44 and 45
Damage to the Broca's area causes:
aphasia (often done in a stroke)
general term for language disorders to include reading, writing, speaking, or comprehension of written or spoken words, generally due to cerebral cortex or conduction dysfunction
Broca's aphasia is also called:
What is Broca's aphasia caused by?
damage to Broca's area, generally in stroke of middle cerebral artery
What happens with Broca's aphasia?
pt can't or has difficulty forming words even though vocal cords and innervations are normal
speech is slow and elaborate, deliberate; pts must concentrate. Applies to speech and writing
Verbally compromised and graphically compromised
Concerning the motor speech cortex, 90% of humans are dominant in which hemisphere?
left, w/ Broca's area strongest on left hemisphere
A pt. presenting w/ stroke and affected leftside will have severe damage to:
Pts w/ right-side stroke will have:
some symptoms but it will be less dramatic than if on left
Broca's aphasia on left side is seen with which side of mm paralyzes of the face and what else?
right sided mm paralyzes of the face and a hemianopsia
What causes Broca's aphasia w/ mm paralyzes of the face and a hemianopsia?
middle cerebral artery
What does non-fluent mean?
words don't flow despite the ability to perceive language and organize though processess
Are pts with Broca's aphasia aware that they can't get words out?
yes, and often become very frustrated
loss of half a visual field
Symptoms of Broca's aphasia:
paralysis of facial mm on the right
can't speak or write
Why does hemianopia occur w/ Broca's aphasia?
because optic pathway and internal capsule are close to Broca's area
What is the name for the language cortex?
Where is the language cortex located?
in posterior part of superior temporal gyrus
What does the language cortex control?
comprehension of spoken words and written and auditory language
10% of the language cortex extends into:
Even though 10% of the language cortex extends into the parietal lobe, it is still considered a function of which lobe?
Which hemisphere is more dominant considering the language cortex?
left (90% of population)
What are some other names for Wernicke's aphasia?
involved w/ comprehension of spoken and written language
able to speak and write words but sequence is not normal, so it doesn't make sense
Is a pt w/ Wernicke's aphasia aware that they don't make sense?
yes, and they often become frustrated
If there is a large lesion on the language cortex, then visual and linguistic ability is:
Wernicke's area must be able to receive input from where?
other areas of the brain
when the wernicke's area is not properly receiving visual or auditory information from other areas of the brain
speaking, but it doesn't make sense
substitute one word for another
create new and meaningless words and put them into senstences
speech is incomprehensible but seems logical to the pt
What artery feeds the Wernicke's area?
middle cerebral artery
What artery feeds the Broca's area?
middle cerebral artery
lesion impairs conduction from Wernicke's to Broca's
In conduction aphasia the Wernicke's and Broca's areas are not specifically damaged, but the lesion destroys the:
efferent connected from Wernicke's to Broca's areas
What are the characteristics of conduction aphasia?
less fluent in language than pts w/ Wernicke's aphasia
may make periphrastic errors
comprehension is good but ability to repeat is limited/poor
naming is impaired
reading aloud is impaired, but pt can read silently w/ good comprehension
writing is abnormal w/ misspelled and omitted words
What are periphrastic errors?
Is writing a function of the Wernicke's or Broca's area?
What is the most severe form of aphasia?
inability to use language in any form due to extensive damage to Broca's, Wernicke's, and arcuate fasciculus
Linguistically and verbally compromised
: unable to read/write well, unable to comprehend speech, unable to produce intelligible speech
Which hemisphere does global aphasia generally occur in?
What is damaged with global aphasia?
A stroke this catastrophic has low survival rates, so this is:
an uncommon presentation
The memory cortex occurs in how many area of the temporal lobe?
Where is the hippocampus?
located deep to the parahippocampus
Damage to hippocampus results in:
would remember previous events (that occurred before damage) but not events that happened after damage
What is another name for the amygdala?
amygdaloid nuclear complex
What is the amygdala?
deeply seated group of nucleui in the telencephalon
What occurs in the amygdala?
initial processing and storage of memory
What happens to memories that don't pass through the amygdala?
it doesn't get remembered
If you are going to remember something consciously, what has to happen?
The info must be processed by the amygdala and the hippocampus