Transcript CNS - BEHS Science

CNS
Central Nervous
System
CNS
Brain and Spinal
Cord
CNS:PROTECTION
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220-221
CNS:PROTECTION
BONE:
Cranium = brain
Vertebrate = spine
CNS:PROTECTION
Meninges: Fiborus
tissue
Color code a,b, b1,c
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)
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.
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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
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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.
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