Neuroanatomy

Question 1

External brain

Answer 1

Lobes
Frontal: precentral sulcus -> personality, executive activities, zipping coat, driving, learning thungs.

Temporal- auditory- right next to ears-

Occipital- 1o visual cortex

Parietal - intacrading input from frontal- see, hear, feel- help u make decisions- higher role- dont understand it yet. - middle of all lobes- injury- hemispacial neglect- unable to integrade senses from opposite body side- neglect that body side

Cerebellum- fine motor control- balance.

Brainstem- midbrain, pons, medulla- input from hypothalamus

BG- movement control- PD + Huntingtons.

Question 2

Sulci

Answer 2

Central sulcus- deepest- middle

Precenral- anterior to central sulcus
Next deepest, less deeper.

Between them- motor cortex- generating movement.

Posterior to central sulcus- sensory cortex- receive info.

Question 3

Cross section of motor or sensory cortex

Answer 3

Lateral down- tongue, jaw, lips, eye, brown, fingers, hand, UE, hip, LE, genitals.

Disproportionality- face-1/3 of motor cortex- lost of fine ability
1/3 extremity
2/3 of motor cortex- hands + fingers= more control.

Sensory cortex- similar.

Question 4

Some infract points

Answer 4

Lateral part of brain- MCA- infract- Face, cingers, hands, upper extremity

Anterior- lower extremities, hips, pelvic musculature
Runs in the middle of brain -ACA

Question 5

Corpus Callosum

Answer 5

Corpus callosum- commincation of hemispheres + ability to integrade 2 sides.
-1o communicating area between 2 sides.

Question 6

What 5 structures make up the Basal Ganglia?

Answer 6

Thalamus
Globus Pallidus
Subthalamic nuclei
Putamen 
Caudate

Substancia nigra

Question 7

Arterial circulation of brain

Answer 7

2- internal carotids and vertebral a take vlood to brain.
Anterior circulation supplied by carotids

Communication- between internal carotids and vertebrals
- willis- internal c, ACA, PCA,

Posterior circulation by vertebrals

Question 8

ANterior circulation

Answer 8

Carotid circulation
1. Common carotid from
2. External and internal carotid
3. PCA-> vertebral + opthalmic a
ACA- medial parietal + frontal
4. Middle C A- lateral cerebrum- temporal, lateral frontal, parietal- Sides.
5. Post communicating a- - back to vertebral- to communicate ant to posterior. -> go round infract.

Ant comm- connects left to right

Question 9

Posterior circulation

Answer 9

2 vertebrals- L+R + ant spinal a + post spinal art from spinal column
↪️ posterior inferior cerebellar arteries-PICA- post lower cerebellum
↪️Basilar a- gives rise
⬇️↪️ L+ R anterior inferior cerebellar artereis (AKA) - ant lower cerebellum
↪️ pontine arteries- on basilar- medulla + pons
↪️ superior cerebelar arteries
Then split
To post communicating artery‼️‼️ give off post cerebral artery

Posterior communicating artery goes back to internal carotid to close rhe circuit.

Question 10

What 2 arteries make up the circle of Willis?

Answer 10

Posterior communicating artery + anterior communicating artery

Question 11

Saccular Berry aneyrism

Answer 11

1. ACA- ant communicating art
2. PCA- post communicating ant
3. MCA- middle cerebral -

SAH- worse headache of my life
Shame
Smokung. , HTN, Adult polycystic , marfans, Elleins deis syndrome

Question 12

Spinal pathways

Answer 12

Sensory- ascending to sensory cortex

Motor- UMN+ LMN- praxis from brain input

Question 13

Dorsal Column- Medial lemniscus- posterior columns

Answer 13

Perception of fine touch, vibration, proprioception
What an object is- blind- u hold indeed a key.
Sophisticated sense of touch.
3 neurones
1o- receptor neuron- DRG- synapse at MEDULLA ‼️‼️ 1st synapse (cunate/gracilis nucleus) cunate- above waste, gracilis- below waist neurones
2o-> decussates at medulla up, synapses in thalamus
3o order neurone- travels to sensory cortex

Spinal Injury:
Ipsilateral loss of fine touch and vibration below lesion- makes sense, they havent crossed yet ❗️
Sensory cortex injury- contralateral loss of fine touch + vibr. Crossed.

Question 14

Spinothalamic tracts

Answer 14

Ascending
Lateral- pain * temp- > no pain
Anterior- crude touch and pressure

1o-> DRG, synapse at spinal cord ‼️1-2 levels up or down,
2o-> decussates at spinal cord, goes up+ synapses in thalamus
3o-> goes to sensory cortex + pain perception areas

Injury:
Contralateral loss of crude touch, pain, temp + pressure
Cz it crosses right away.
Just left side- lost below lesion on right side.
Sensory cortex injury- contralateral again- cz the both already crossed.

Question 15

What to remember about spinal injury?

Answer 15

If injury is before decussation- lose it in ipsilateral side,
If its After- contralateral side

Question 16

Corticospinal tract- what is it

Answer 16

Motor- descending starting at motor cortex
UMN-> lower medulla-> 25% decussate immediately
75% -> decussation of pyramids in lower medulla!
After decussation, down SC and synapses w/ LMN (2o) ,will exit at the anterior horn (sensory enters dorsal horn) -> to traget muscle

Lateral-> larger one- limb musculature- arms + legs

Anterior CST
-> axial musculature- abdo, trapezius,back muscles,