Transcript Slide 1
CHAPTER 7b: Nervous System Protection of CNS Meninges = three membranes covering the CNS structures (p 211) Duramater = outermost layer Dura = hard Mater = mother netterimages.com schools-wikipedia.org Arachnoid Mater = web-like middle layer commons.wikimedia.org Arachno = spider Pia Mater = innermost layer following folds commons.wikimedia.org pia = gentle Meningitis = inflammation of meninges http://video.about.com/infectiousdiseases/Meningitis.htm http://www.nmaus.org/programs/getting-it/ http://www.healthline.com/hgy-transcripts/meningitis-overview http://healthline.healthology.com/hybrid/hybridautodetect.aspx?content_id=2582&focus_handle=childrensdiseases&brand_name=healthline Continually made from blood plasma in choroid plexuses which hang from the “roof” of the brains ventricles. Circulates continuously by being produced and then drained back into blood plasma to keep a constant volume of about 150 ml. Function: protection Spinal Tap = sampling technique to test CSF. Hydrocephalus = “water on the brain” Cerebrospinal Fluid (CSF) = fluid surrounding the brain and spinal cord Keeps neurons separated from blood-borne substances. BLOOD-BRAIN BARRIER Made of LEAST PERMEABLE capillaries in the body. vandenberg.af.mil Can’t keep out fats, respiratory gases, alcohol, nicotine, or anesthetics. Brain Injuries Traumatic Brain Injuries and Brain Dysfunctions Head injuries are the leading cause of accidental death in the USA. Concussion = slight injury, dizziness, brief loss of consciousness. http://www.pennmedicine.org/encyclopedia/em_DisplayAnimation.aspx?gcid=000034&ptid=17 Contusion = marked tissue destruction, coma Cerebral Edema = swelling of the brain, death Stroke = cerebrovascular accident (CVA) occurs when circulation is cut off to the brain. http://www.pennmedicine.org/encyclopedia/em_DisplayAnimatio n.aspx?gcid=000123&ptid=17 Aphasia = result of damage to left cerebral hemisphere, affects speech. motor aphasia = affects Broca’s area and loss of speech sensory aphasia = loss of understanding of language TIA = transient ischemic attack (mini-stroke) BrainMatters 54:00 http://video.pbs.org/video/1390247671/ Alzheimer’s Disease • mental deterioration • progressive degenerative disease • originally called “senile dementia” • memory loss, irritability, moodiness, confusion, possibly violent • later stages include hallucinations topnews.net.nz articles.mercola.com Dementia 1:01 http://www.healthscout.com/animation/1/7/main.html Alzheimer’s Disease 19:10 http://www.alzheimer.ca/english/disease/whatisit-video.htm Alzheimer’s Disease Spinal Cord About 17 inches (42 cm) long. 31 pairs of nerves arise from it. Motor neurons Sensory neurons Textbook page 217. Association neurons White matter of the spinal cord Quadriplegic = damage high in cord Paraplegic = damage low in cord