1-6-12 Friday

PHYS/PATH

Diencephalon
-Thalamus (old time telephone operator):sorts sensory inputs; directs impulse within cerebral cortex
-Hypothalamus:
maintains homeostasis
controlas sympathetic and parasym. a division of ANS
influences heart beat, blood flow, hormone secretion
only part of brain in contact with blood
says when full

Limbic system
b/w cerebrum and diencephalon
-involved in emotional states, behavior, learning, long term memory
stimulates reticular formation?
link function of cerebral cortex and brain stem

Brain Stem
-connects cerebrum and diencephalon with spinal cord
-composed of midbrain, pons, medulla oblongata:

midbrain
-superior part of BS
-4 masses form superior part of midbrain
-reflex involving eyes and ears
-conducts impulses between higher centers of cerebrum and lower centers of pons,and others

Pons:
-connecting link b/w cerebellum and rest of nervous system
-mainly respiration

Medulla Oblongata: (survival type reflexes)
-respiratory, cardiac, vasomotor centers
-contralateral control


Cerebellum
3parts
-Vermis, left and right hemisphere

function
-coordinate voluntary mm (smooth mvmts out)
-maintain balance
-maintain mm tone

Brain studies:
CT scan- computed tomography
MRI- magnetic resonance imaging
PET- positron emission tomography

electrocephalograph
records electric currents given off by brain nerve cells
sleep
diagnose disease
locate tumors
study drag effect
determine brain death

Cranial nerves! p.180-81)
12 pairs
4 categories
-special sensory impulse
-general sensory impulse
-somatic motor impulse
-visceral motor impulse

I. olfactory
II. optic nerve
III. oculomoto
IV. trochlear
VI. auducens
V. trigeminal
-ophthamic
-maxillary
-mandibular
VII. facial
VIII. vestibulocochlear
IX. glossopharyngeal
**X. vagus
XI. accessory
XII. hypoglossal

Aging nervous system
decrease brain size and weight
decrease speed information process
slowed mvmt
diminished memory
reduced blood flow to brain

CHAP. 10 Sensory system

The senses detects environmental changes
this initiates nerve impulses (stimulus)
stim interpreted by cerebral cortex
sensatoin

Sensory receptors (afferent)
structure
-free dendrite of sensory neuron
-end-organ on dendrite of afferent neuron
-specialized cell ass. with afferent neuron

type of stim/ receptors
chemo-chemical
photo-light
thermo-heat
mechano-mvmt

specialized
vision
hearing
equilibrium
taste
smell

general
pressure, temp, pain, touch
sense of position (like to know where head is)

Eye and Vision
eye protection structure
-eye cavity bones
-eyelids, lashes, brow
-conjunctiva
-lacrimal gland (tears produced)

Coats of eyeball
tunics (same as meninges of brain)
-sclera
-choroid
-retina

cornea, aqueous humor, lens, vitreous body

function of retina
-detects light and color
rods: dim light, shades of gray, blurred image
cones: bright light, color sensitive, sharp image
connects neurons

MM of eye
-intrinsic: lens and iris (adrenal gland stuff)
-extrinsic: outer surface, voluntary

Ear: hearing and equilibrium
outer and middle are air filled/hollow
inner is fluid filled

Outer
-pinna (aurick): directs sound waves into ear
-external auditory canal (meatus): ceruminous gland
-tympanic membrane (ear drum): vibrates as sound waves enter ear

Middle ear and ossicles (small bones inside) amplify sound waves and transmit sounds
-malleus (hammer)
-incus (anvil)
-stapes (stirrup)
Eustachian tube
-connects mid ear with throat (pharynx)
-allows pressure equalize on both sides of tympanic mem.
-continuous mucous mem. form pharynx to mid ear cavity

Inner ear
bony and membranous labyrinth
-vestibule (forward and back)
-semicicular canals (acts as level)
-cochlea
-perilymph fluid (bony); endolymph fluid (membranous)

hearing organ corti
-located in membranous cochlea (cochlear duct)
-ciliated receptors cells
-tectorial membrane

Equilibrium
located in vestibules and semicircular canals
types of equilibrium
-Static
vestibule: F/B (moving?)
maculae receptors
otoliths fluid
-Dynamic (more directions)
semicircular canals
cristae receptors

Taste; on tongue; basics are sweet, salty etc....
Smell; nasal cavity
-stim by subst. in solution in nasal fluids
-smells stims appetite and flow of digestive juices
olfacotry nerve (cranial nerve I)

Touch
-baroreceptors monitor BP and respond
Pressure
Temp.
Position
-proprioceptors (position)
-in mm, tendon, joints
-relay impulses in body parts in relation to each other
-send impulse to cerebellum for coord.

Pain and relief
different nerves fire at different rates


PATHOLOGY-chapter 4-nervous system

numbness can be more dangerous than pain
(non)verbal communication
meds

Alzheimer (AD) progressive degenerative brain disorder
-memory loss
-dementia
-personality change

-plaques (beta amyloid deposits)
-neourfibrillary tangles (tau protein)

chronic inflammation, injury, gluten? may be causes

Amyotrophic Lateral Sclerosis (ALS, Lou Gehrig disease)
progressive degen of motor neurons usually CNS but also PNS
starts as spasm in hands

Multiple Sclerosis (MS)
autoimmune, destroys mylein sheath
can be seen on both sides of body
pain, vision, bladder
symptoms come and go

Peripheral Neuropathy (PN)
issues with PNS damage
injury
infection
systemic disease
toxic exposure
Tx: antidepressants, TENS, etc.
numbness and pain

Dystonia
repetitive, involuntary, sustained contraction in skel. mm.
issue with basal gangia
burst of elect. activity
similar to parkinson, tourette, neck injury

Parkinson Disease
shaking palsy
prog. degen. mvmt disorder
dopamine problem with basal cell ganglia
*causes Lewy bodies build up (a protein)
S&S: resting tremor, bradaykinesia
Tx: meds, others

Tremor: rhythmic oscillation (a symptom)
an essential tremor
Huntington's disease


infection = systemic contra.

Encephalitis
infection of brain
usually viral
with myelitis, meningitis
primary
secondary: herpes simplex, measles, mumps,

Herpes Zoster
'shingles' extremely painful