Neuralation happens in week of embryonic development. The brain, the spinal cord, and all originate from the neural tube. Meanwhile the ganglia of the spinal and cranial nerves, the ganglia, and cells are all from the cells.

is a cephalic disorder in which the fails to give rise to two hemispheres. The child could be born with (one eye-- like a cyclops.)

Mutations in the gene encoding for the protein can cause this condition.

signs are ipsilateral but signs are contralateral.

Vasculature:
give rise to and cerebral arteries

arteries give rise to two arteries, the artery, and the artery (trunk for the Circle of Willis.)

Blood vessel occlusions in the brain can present differently:

If the anterior cerebral artery becomes blocked, there will be a loss of strength and sensation in the part of the body.

If the middle cerebral artery becomes blocked, there will be a loss of strength and sensation in the parts of the body.

If the posterior Cerebral Artery becomes blocked, there will be /sensory defects with little to no motor loss. Most notably, there will be .

Cranial Nerves 2 and 3:

Optic nerve:
Visual
Visual fields
and Pupillary reflux

Oculomotor nerve is an pupillary reflex.

Partial optic nerve lesion (lesion within the nerve): Causes .

2. Complete optic nerve lesion: in that eye.

3. Optic chiasm lesion:

4. Optic tract lesion:

5. Meyer’s loop: PITS ( , )
(temporal pathway) lesion: upper .

6. Optic radiation lesion:

7. Visual cortex lesion:

8. Bilateral macula cortex lesion: scotomas

Eye Movement pneumonic:
(SO4LR6)3:
is by trochlear (4)
is by abducens (6)
Everything else is (3)

is the crossing from one side of the central nervous system to the other

Major sensory pathways:

(Medial Lemniscus)
and
Tract.

Major motor pathways

The upper motor neurones:
(pyramidal)
and
tracts.

The spinal cord ends at level /. The lower and nerves travel down to exit at their corresponding level, forming the .

While an can be done at any level, spinal anesthesia should be done below this level.

How CSF flows:

1. Arachnoid --> 2. ventricles--> 3. Foramen of --> 4. ventricle--> 5. --> 6. Ventricle--> 7. and lateral --> 8. space

In Multiple sclerosis, there is damage to the which leads to a loss of in the hands and fingers.

  is the expansion of the which leads to tract damage as the axons are damaged.
The presentation is: loss of and detection in the upper limbs.

In Amyotrophic Sclerosis, the tracts are damaged (upper motor neuron lesions) as well as neurons (lower motor neuron lesions.)

– Syndrome is the hemisection of the spinal cord.

Ipsilateral to the lesion, the presentation is:
neuron signs due to damage to the corticospinal tract
Loss of due to damage to the dorsal column-medial lemniscus tract

Contralateral to the lesion, the presentation is:
Loss of and due to damage to the spinothalamic tract

The test is a test of the body's sense of positioning (), which requires functioning of the of the spinal cord. A patient who has a problem with proprioception can still maintain balance by using and .

The standing patient is asked to close his or her eyes. A of is interpreted as a positive finding.

The branch of the middle meningeal artery runs under the , which is the region where the frontal, parietal, temporal, and bones fuse. It is located on the side of the skull, just the temple. This artery runs through the .

Trauma to this vessel is the easiest and most common way for one to get a hematoma.

The - doctrine states that three things exist within the fixed dimensions of the skull: , cerebrospinal fluid, and the brain. An increase in any one component must lead to a in one (or both) of the other components, otherwise the pressure will increase.

If the pressure is severe enough, this can lead to of brain tissue out of the skull. If this occurs at the brainstem, it can lead to or even brain .

: is an extension of the mater that separates the cerebellum from the inferior portion of the lobes.

is a strong, arched fold of mater that descends vertically in the between the cerebral hemispheres. It is narrow in front, where it is attached to the galli of the ethmoid; and broad behind, where it is connected with the upper surface of the cerebelli.

CSF is acts as a cushion for the brain's , providing basic mechanical and protection to the brain inside the skull. It also impacts cerebral autoregulation of cerebral .

dysphasia (AKA ) is when one can speak fluently but cannot comprehend nor speak comprehensively. Because the patient is of this, the prognosis is poor.

dysphasia (AKA ) is when one can fully comprehend but has difficulty replying/speaking. They are often very frustrated and recovery is fully capable. is also affected.