M116

• What are ventricles?

  Chambers in the brain filled with fluid (cerebral spinal fluid). The choroid plexus makes the CSF by filtering blood and leaving plasma
• How many ventricles does the brain have?

  4
• Lateral Ventricles

  Two total

  One in each hemisphere

  C-shaped
• Telencephalon

  Lateral ventricle

  structures: cerebral cortex, basal ganglia, cingulate gyrus (limbic system), corpus callosum, fornix, (septal nuclei), anterior commissure
• Vertebral Arteries

  Blood goes up through these two arteries, up the spinal cord, to deliver oxygenated blood to the brain
• Basilar Artery

  When the vertebral arteries get to the pons, the two arteries fuse into one midline vessel
• Posterior Cerebral Arteries

  Once the basilar artery travels through the pons, it splits again and has one going to the left and one to the right.

  Carries blood to the occipital and inferior temporal lobe
• Internal Carotid Artery


  Another source of oxygenated blood from the heart —> if 3D while looking at ventral side, they would be sticking out at you (hollow tubes)
• Middle Cerebral Artery

  Carries blood to lateral surface of the brain's hemispheres
• What would happen if a blood clot traveled through the middle cerebral artery?

  Ischemic stroke bc blockage
• How many anterior cerebral arteries?

  Two
• Anterior cerebral arteries

  These two go in between the hemispheres and supply blood to the medial surfaces of both hemispheres
• Anterior communicating artery

  Connects both anterior cerebral arteries
• What does the anterior communicating artery look like?

  A bridge
• Foramen of Monro

  Two holes on each lateral ventricle
• Where does the third ventricle get CSF from?


  From lateral ventricles through Foramen of Monro
• Where does the CSF from the third ventricle go?

  Out of third ventricle to the fourth ventricle through Cerebral aqueduct
• Cerebral aqueduct


  CSF flows out of third ventricle --> fourth via this aqueduct
• Where is the third ventricle?

  Squished btwn the two hemispheres (very skinny)
• What shape is the fourth ventricle? Where is it?


  Triangular

  squished between the cerebellum and brainstem
• Foramen of Magendie

  Hole in the medial section of the fourth ventricle
• Magendie starts with M so medial
• Foramina of Luschka

  Holes in the lateral sections of the fourth ventricle
• Which way does the CSF flow out of the Foramina of Luschka?


  The sides

  Luschka starts with L so think lateral
• Where does CSF go after it leaves the Foramen of Magendie and Foramina of Luschka?

  EVERYWHERE (that there is space)
• What is the only structure in the myelencephalon that we can see?

  The pyramids
• Pyramids

  Bundles of exons that are a part of the spinocortical tract
• What makes up the myelencephalon?


  Pyramids

  4th ventricle
• Can we see the fourth ventricle? If not, what is there instead?


  No, instead we are just looking at a space where there used to be fluid
• Metencephalon

  • trapezoid bodies
  • 4th ventricle
  • cerebellum (dorsal side)
  • pons
• LGN (Lateral Geniculate Nucleus) is a part of the diencephalon
• LGN receives projections from retinal ganglion cells
• LGN receives projections through the Retino-geniculo-calcarine pathway
• LGN projects to V1 (Striate cortex or Area 17)
• Damage to the auditory pathway usually results in bilateral hearing loss
• Damage to the cochlea leads to unilateral hearing loss
• Ventral cochlear nucleus projects to the superior olivary complex, causing bilateral hearing loss
• Dorsal cochlear nucleus does not synapse on the superior olive and does not form trapezoid bodies
• Inferior colliculi communicate with each other, leading to bilateral hearing loss
• Superior olives are responsible for sound localization in the horizontal plane