Neuroanatomy- brain stem

Horizontal/axial cut

coronal cut

sagittal

why are ventricles good in neuroanatomy

they are a good indicator of where you are at in a specific plane.

4 roles of CSF

protection, buoyancy, nutrition, waste removal

sensory input from the body

ascends to the brain

motor output from the brain

descends to the body

dorsal horn

secondary sensory neurons

ventral horn

motor horn

divisions of the spinal cord

cervical, thoracic, lumbar, sacral, and coccygeal.

why might someone feel pain in their arm when they have a heart attack?

the pain sensations are being innervated from the throacic nerves.

cervical

throacic

lumbar

sacral

why is there more white matter in the cervical division

it carries all of the ascending and descending neurons which require strong sending signal from your axons.

Why isn’t there much gray matter in the thoracic level?

Your chest moves more in a signal motion than it needs multiple movements.

what is in the brain stem?

have ascending and descending pathways to/from the body and the brain

important for sleep, heart rate, breathing, and neurotransmitter production

Cranial nerves: nerves carrying sensory and motor information to/from the face/head and the brain

Ascending tract: Dorsal columns, primary neuron cell body

dorsal root ganglion

Ascending tract: Dorsal columns, primary neuron synapses

in dorsal column nucleus: gracile for lower body and cuneate for upper body

Ascending tract: dorsal columns, secondary neuron cell body

cell body in dorsal column nucleus (gracile or cuneate) synapses in thalamus

ascending tract: dorsal columns teritiary neuron cell body

thalamus

ascending tract: dorsal column teritary neuron synapses

in the cortex

gracile

legs and trunk

cuneate

arms/hands

where is the dorsal column system in the lower medulla in the DCM

gracile, cuneate

where is the dorsal column system in the upper medulla in the DCM

medial lemniscus

where is the dorsal column system in the pons in DCM

medial lemniscus

Where is the dorsal column system in the midbrain in the DCM

medial leminscus

where is the dorsal column system in the thalamus in DCM

ventral posterior lateral nucleus

where is the dorsal column system in the cortex in DCM

primary somatosensory cortex

lower medulla

upper medulla

pons

midbrain

Descending tract: Corticospinal tract

send information about conscious motor control from brain to body

primary neuron of corticospinal tract

cell body in motor cortex, synapses in the spinal cord

secondary neuron of corticospinal tract

cell body in spinal cord, synapses on muscle

axons of primary neurons in corticospinal tract

travels in the corona radiata then internal capsule

axon of the primary neuron is where in the midbrain

cerebral peduncles

axon the primary neuron of the corticospinal tract is in the ventral part

of the pons

axon of the primary neuron of the corticospinal tract is where in the midbrain

cerebral peduncles

axon of the primary neuron is where in the upper medulla

pyramid

axon in the primary neuron of the corticospinal tract is where in the lower medulla

pyramid

axon of the primary neuron in the corticospinal tract crosses where

in the lowest medulla, pyramidal descussation

where does it synapse from the lateral corticospinal tract

synapses in the ventral horn