3/4- External features of the Spinal cord

The spinal cord begins superiorly at the - - - - in the skull, where it is continuous with the - - - -of the brain, and it terminates inferiorly in the adult at the level of the - - - -.

foramen magnum

medulla oblongata

lower border of the first lumbar vertebra

There are 2 enlargements in the spine, where are they located?

where the plexuses are

• Cervical region (for brachial plexuses)

• Lumbar region (for lumber plexuses)

The spinal cord tapers into:

Conus medullaris

What is the Cerebral cortex?

outer layer of grey matter.

Association fibers

•Interconnect cortical sites lying within one hemisphere.

They are short or long fibers

Commissural fibers

•Connecting  functionally related gyri on both hemisphere.

Projection fibers

Connecting the cortex with the lower centers in thalamus brain stem, or spinal cord.

They are ascending or descending

Broca’s Area

Controls facial neurons, speech, and language comprehension

Where is Broca’s area located?

Located on Left Frontal Lobe

Parietal Lobe function

• Senses and integrates sensation(s)

• Proprioception - Awareness of body/ body parts in space and in relation to each other

Primary Gustatory Cortex

Primary site involved with the interpretation of the sensation of Taste

exteroceptive sensation receptors location:

On skin + mucosa

Proprioceptors are located

deeper layer of the skin - joints - tendons - Golgi Tendon Organ - etc (Within the body)

Where is the 1st order order neuron cell body?

post. root ganglion

2nd order neuron where?

post. grey column of spinal cord

Which ascending neuron decussate/ cross the the midline?

2nd order neuronWher

Where is the third order neuron cell body?

in the thalamus

(VPL nucleus specifically)

Clinical application destruction of LSTT(lateral spinothalamic tract):

Loss of:

• pain and thermal sensation in contralateral side + bellow the lesion.

patient will not:

•   respond to pinprick 

•   recognize hot and cold

•transmit unconscious proprioceptive information to the cerebellum

Posterior & anterior spinocerebellar tract

The basilar artery ends by dividing into:

2 posterior cerebral arteries

Extrapyramidal system acts on

Lower motor neurons

Injury to Wernicke’s area results in:

Sensory aphasia

What type of neurons are in the dorsal root ganglia?

Pseudo-unipolar neurons

What is the continuation of the pia matter bellow the spinal cord?

The filum terminale, which anchors the spinal cord to the coccyx.