What is the point of solving neurological problems?
want to know where the vertical information transects the horizontal info
What is the vertical info?
coming from some area in Sc and terminating in pre-central gyrus
Name the vertical information:
- spinothalamic tract (spinal lemniscus)
- dorsal column (fasciculus gracilis and fasciculus cuneatus) --medial lemniscus
- spinocerebellar tract
- corticospinal tract
- corticobulbar tract
- trigeminal lemniscus
What is horizontal info?
always there and doesn't move
Name the horizontal info:
- all CN and their pathways
- motor and sensory CN nuclei
- specific parts of brain: basal ganglia, cerebellum, internal capsule, hypothalamus, thalamus, crus cerebri, etc
- spinal nn and ventral horns of SC
- absence of reflexes
Why is horizontal info better?
b/c it locks into which part of cortex is not working
Where is the lesion?
where the vertical and horizontal info cross
Pt lost proprioception from L side of body and experienced adduction of R eye, where is the lesion?
- uses Dorsal column pathway so lesion is in:
- R Pons
Pt lost pain and temp from L side of body and experienced flaccid paralysis of facial mm on R side, where is the lesion?
- uses spinothalamic and CN VII (motor nuclei in pons)
- Therefore, lesion is in R Pons
What are the different types of aphasia?
What does the motor speech cortex allow?
initiation of speech y influencing portions of precentral gyrus that control skeletal m for speech (larynx, pharynx, tongue, face, and mouth)
Where is the Broca's area?
located around inferior frontal gyrus in frontal lobe
What is the Broca's area?
- primary cortex for motor speech
- technically association area of frontal lobe that finesses pre-central gyrus
Broca's area = Broadmann's areas:
44 and 45
What does damage to the Broca's area cause?
Broca's aphasia (often done in a stroke)
general term for language disorders to include reading, writing, speaking, or comprehension of written and spoken words, generally due to cerebral cortex or conduction dysfunction
Broca's aphasia (motor aphasia, non-fluent aphasia):
- caused by damage to Broca's area
- generally in stroke of middle cerebral A
- pt con't or has difficulty forming words even though vocal cords and innervations are normal "cerebral cortex dysfunciton"
What are the symptoms of Broca's aphasia?
speech is slow and elaborate, deliberate; pt must concentrate
Does Broca's aphasia apply to speech or writing?
How is a pt with Broca's aphasia compromised?
verbally and graphically
90% of humans are dominant in which hemisphere?
90% of humans have the Broca's area strongest in which hemisphere?
Pt presenting w/ stroke and affect R-side will have severe damage to:
Broca's area (L hemisphere)
Why is Broca's aphasia considered non-fluent?
words do not flow, despite ability to perceive language and organize thought processes
Are pts aware that they can't get words out?
yes, and they get very frustrated
What problems often accompany Broca's aphasia?
hemianopsia and paralysis of facial mm on R
loss of half a visual field
What 3 symptoms usually appear together concerning Broca's area?
- Broca's aphasia
- paralysis of facial mm on R
Why do Broca's aphasia, hemianopsia and paralysis of facial mm on R often appear together?
b/c optic pathway nad internal capsule are close to Broca's area
What is the language cortex called?
Where is the Wernicke's area?
90% in posterior part of superior temporal gyrus
What does the Wernicke's area control?
comprehension of spoken words and written and auditory language
Where is the other 10% of the Wernicke's area located?
extends into parietal lobe (still considered a function of temporal lobe)
Which hemisphere is more dominant considering the Wernicke's area?
L hemisphere in 90% of population (same as Broca's area)
Wernicke's aphasia (fluent aphasia, receptive aphasia):
involved w/ comprehension of spoken and written language
What happens with Wernicke's aphasia?
able to speak and write words but the sequence is not normal, so they don't make sense
Are pts aware that they don't make sense?
yes and they become frustrated
How is a pt compromised with Wernicke's aphasia?
How is a pt compromised with Wernicke's aphasia if it is a large lesion?
visual and linguistic ability compromised
Wernicke's area must be able to receive input from where?
other areas of brain
What happens when the Wernicke's area doesn't receive visual or auditory info properly?
- part of Wernicke's aphasia
- speaking but it doesn't make sense
What are sub-types of empty speech?
- jargon aphasia
substitute one word for another
- create new and meaningless words and put them into sentences
- (that have nothing to do with the sentence)
- words and phrases are strung together w/ no meaning
- speech is incomprehensible but seems logical to pt
Which artery feeds the Broca's and Wernicke's areas?
middle cerebral A
occurs when something impairs the conduction from Wernicke's (language comprehension) to Broca's (speech formation)
With conduction aphasia, what exactly is damaged?
arcuate fasciculus (efferent connection 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 paraphasic errors (substitution of 1 word for another)
- comprehension is good, ability to repeat is limited/poor
- naming is impaired
- reading aloud is impaired, but pt can read silently w/ good comprehension
- writing (Broca's) is abnormal w/ misspelled and omitted words
- most severe form of aphasia
- inability to use language in any form due to extensive damage to Broca's, Wernicke's, and arcuate fasciculus
How is a pt compromised with global aphasia?
linguistically and verbally (unable to read/write well, unable to comprehend speech, unable to produce intelligible speech
Which hemisphere does global aphasia generally occur in?
Is global aphasia a common presentation?
no b/c a stroke this catastrophic has low survival rates
impairment of voluntary skeletal m activity which is not due to lack of comprehension, innervation, or mm physiology (something wrong w/ specific part of cortex...that means it is horizontal issues)
impairment of ability to recognize, or comprehend the meaning of sensory stimuli due to lesions of the cerebrum
R and L sided neglect are due to damage in which lobe?
Primary functional areas of cerebral cortex:
- REVIEW THESE ON OWN
- look to previous notes...
- caused by strokes
- loss of visual fields affect similar location for 2 eyes (homonymous)
- hemianopsia: loss of visual fields in each is is 1/2
- L homonymous hemi=loss of L half of visual field in both eyes