Wednesday, February 4, 2009 Lecture

During Wednesday's class we focused mainly on the Central Nervous System. We discussed the Meninges (coverings) on the brain, which include 3 distinct layers: the dura, arachnoid, and pia mater. We also learnt about the production of cerebrospinal fluid (CSF) and the flow of CSF throughout the ventricles of the brian and the spinal cord. In addition to CSF, we also discussed the flow of blood to and from the brain, and key facts about the blood flow, such as the anatomical redundancy (that creates a "back-up" flow blood to the brain in case of injury, trauma, etc. The major areas of the brain, the lobes, and their functions were also learnt. Lastly, we discussed seven of the twelve cranial nerves, including the three sensory nerves: I olfactory, II optic, and VIII vestibulocochlear; and four of the motor nerves: III oculomotor, IV trochlear, VI abducens, and XI accessory. We discussed the functions of these 7 cranial nerves, as well as their exit points through the skull.
One disorder that has always been confusing to me is that of blindness. If I were to pick one sense or function to keep over anything else, it would be vision. After our discussion of the optic nerve, one of the twelve cranial nerves, I researched what exactly causes blindness. Although blindness may be caused by such diseases as diabetes or malfunctioning of the retina, one reason it may occur is because of damage to, or the malfuncitoning of, the optic nerve. If the nerve does not develop correctly, blindness may develop from birth, however, one may also become blind if the optic nerve is damaged through trauma.