Central Nervous System CNS Central Nervous System

CNS Brain and Spinal Cord

CNS:PROTECTION Turn to page 220-221

CNS:PROTECTION BONE: Cranium = brain Vertebrate = spine

Meninges: Fiborus tissue Color code a,b, b1,c CNS:PROTECTION Meninges: Fiborus tissue Color code a,b, b1,c

Dura Mater: Toughest connective tissue CNS:PROTECTION Dura Mater: Toughest connective tissue Right under cranium

CNS:PROTECTION Arachnoid: Spider-web covering under dura mater.

CNS:PROTECTION Subarachnoid: Pockets of the arachnoid that contain cerebral spinal fluid (CSF)

Pia Mater: Delicate, contains many blood vessels. CNS:PROTECTION Pia Mater: Delicate, contains many blood vessels.

CNS:PROTECTION CSF: Circulates subarachnoid space Cushions, and nourishes. Surrounds entire CNS

Ohio State University: Neurology: College of Medicine. CSF from the lumbar region contains 15 to 45 mg/dl protein (lower in childen) and 50-80 mg/dl glucose (two-thirds of blood glucose). Protein concentration in cisternal and ventricular CSF is lower. Normal CSF contains 0-5 mononuclear cells. The CSF pressure, measured at lumbar puncture (LP), is 100-180 mm of H2O (8-15 mm Hg) with the patient lying on the side and 200-300 mm with the patient sitting up.

Problems Increased protein: In bacterial meningitis, CSF protein may rise to 500 mg/dl. A more moderate increase (150-200 mg/dl) occurs in inflammatory diseases of meninges (meningitis, encephalitis), intracranial tumors, subarachnoid hemorrhage, and cerebral infarction. A more severe increase occurs in the Guillain-Barré syndrome and acoustic and spinal schwannoma.

Problem Xanthochromia (blonde color) of the CSF following subarachnoid hemorrhage is due to oxyhemoglobin which appears in 4 to 6 hours and bilirubin which appears in two days. Xanthochromia may also be seen with hemorrhagic infarcts, brain tumors, and jaundice.

Faint yellow, orange or pink (Xanthochromia) Normal Clear as water Abnormal findings Faint yellow, orange or pink (Xanthochromia) CSF Protein >100 mg/dl Red Blood Cell lysis Red Blood Cell >100,000/mm3 (Subarachnoid Hemorrhage) Cloudy or turbid CSF Leukocytes > 200 wbc/mm3 Red Blood Cells > 400 per mm3 Brown or Dark CSF Metastatic Melanoma (meningeal Melanomatosis) Jaundice (Hyperbilirubinemia) Green CSF Hyperbilirubinemia Purulent cerebrospinal fluid

(1) intervertebral discs, (2) vertebral bodies, (3) dura, (4) epidural space, (5) spinal cord, and (6) subdural space

BRAIN

BRAIN Folded to increase surface area 35 billion neurons (98%) Adult = 3 lbs

Brain Brain (3 lbs) at rest needs as much oxygen as 61 lbs of skeletal muscle.

Brain Turn to page 224

BRAIN Gyrus: Peaks of the folds, ridges. Sulcus: furrow or groove between gyrus

Brain Ventricles: CSF circulate in four major canals. (Travels through brain and into spine) Continuous. Blue on page 228

BRAINSTEM

BRAINSTEM Lower brain Unconscious part

BRAINSTEM COLOR CODE: Med. Oblongata = k Pons = f Midbrain = a Reticular formation = g

MEDULLA OBLONGATA Breathing Heart rate Reflex center

PONS Connects cerebellum to cerebrum Breathing

Midbrain Like a hook Diencephalon to cerebrum Eye reflexes

Reticular formation Fibers in the middle of brainstem (connects to RAS) Inactive so are you! Consciousness.

Diencephalon

COLOR Color code the Diencephalon to the right. Thalamus = a Hypothalamus = b

Diencephalon On top of brainstem

Thalamus Relay station for sensory headed to the cerebrum. Filters out messages.

RAS Reticular Activation System Deals with arousal and consciousness.

HYPOTHALAMUS Maintains homeostasis (temp) Emotions: Rage, pleasure, pain, thirst, hunger

COLOR CODE On middle picture page 10 Cerebellum = h Arbor Vitae = i

CEREBELLUM Controls muscle balance and coordination. Lower, posterior part of brain.

White “tree-shaped” structure inside cerebellum. Arbor Vitae White “tree-shaped” structure inside cerebellum.

Cerebrum Color code Frontal = a, a1, a2 Parietal = b, b1 Temporal = c, c1 Occipital = d, d1

Cerebrum Outer layer, largest region, called cortex About 1 inch thick 4 lobes

Frontal lobe Higher level thinking Personality, speech center.

Parietal Lobe Sensory for touch and pain

Temporal lobe Sensory for hearing and smell

Occipital lobe (back) Sensory for vision

Brain time

Limbic system Area around center of brain. Not too much known about area.

Limbic system Emotion: Emotional states, fear, rage and sexual arousal.

Limbic system Memory and learning: Long term memory and retrieval (hippocampus) (learning)

Lateralization Brain divided laterally into 2 hemispheres. Connected by corpus callosum

Lateralization RIGHT  music, art, creative Left  math, verbal