18 JULY : EXAM 4 Flashcards
list in order the level of consciousness:
coma vegetative minimally conscious state stupor / obtunded delirum (add syncope)
syncope is
fainting
delirium is
more about cognition than consciousness
more fully awake but not processing correctly (loopy)
stupor / obtuned:
level of interaction diminished
ie: us in class:
fade sleepy
minimally conscious state:
min interaction with the environment
has a sleep-wake cycle
vegetative:
has sleep-wake cycle
no interaction
coma:
no sleep-wake
no interaction with the environment
a brainstem tumor means you have
an increase in intracranial pressure
list 3 major signs and symptoms of brainstem tumors:
nausea
vomiting
headache
why do we get vomiting from a brainstem tumor:
so some nerves become active when they “fall asleep” ischemic - whatever is happening to our bodies we don’t like so your body tries to get rid of it: induce vomiting
your visual field do three things for you?
- sight
- eye movement
- postural and limb movement
sight has two things involved in it
recognition and location of objects
4 cranial nerves go into sight what are they
optic
oculomotor
abducens
trochlear
the two retina in the eye are:
nasal and temporal
the nasal bone is near the
nose bone so on the inside
the temporal bone is near the
temporal bone so on the outside
the retina is determined by:
what bones they are at
the nasal retina picks up the
temporal visual field
the temporal visual field picks up the
nasal visual field
what does the optic nerve do for sight
turns APs of light into visual acuity
oculomotor does two things
parasympathetic control of sight
moves the eye around
the lenses of the eye is a
inverted phrism
fx of the retina ganglia cells:
convert APs from light goes form retina to the occipital lobe
six parts of the eye X
optic nerve optic chiasm optic tract geniculate nucleus pretectal area visual cortex
chiasm does what
the sight of the “crossing”
all the information of the visual field does what
cross overs to the other side for processing
sight information goes where?
cerebral cortex
sight goes where so has to pass through where?
the cerebral cortex
passes through the thalamus (lat geniculate nucleus)
where does sight end?
the cerebral cortex of the occipital lobe
there are two streams:
dorsal and ventral
the goal of crossing over
get all of the axons for the opposite visual field is on one side of the body
fx of the superior colliculus
turns head towards the sight
the two streams come from where?
the primary and secondary visual cortex
the dorsal stream fx is
use what I see to create a visual plan to move
the ventral stream fx is
for perception
gives name and meaning to what you see
dorsal stream ends in the
motor planning area
ventral stream ends in the
inf. temporal lobe
blindness in one eye affects
the optic nerve
bitemporal hemianospia affects the
nasal retina dx
homoymous hemianopsia affects the
optic tract
quadrantanopsia affects the
optic radiations
when you are blind in one eye a major deficit is
loss in depth perception
ie of bilateral hemianospia:
tunnel vision
ie of hommonymous hemianopsia
unilateral neglect
ie of quadrantanopsia:
pie on the floor
processing of visual information involves what structures
retina –> thalamus–> visual cortex
- action
- visual identification of object
if you were to dx your optic nerve you would get
unilateral blindness
if you were to dx your optic tract you would get
homonymous hemianposia
if you were to dx your nasal retina you would get
bitemporal hemianposia
if you were to dx your optic radiations you would get
quadrantanopsia
if you were blind you could still see
light / dark differences “shapes”
tectum fx
orient head
pretectal areas include
the pupillary reflexes
- when you shine light eyes automatically respond w/ decrease in pupil
pupillary light reflex df
when you shine to light your eyes automatically respond with decreased pupil size
what structures affect the pupillary light reflex?
the pretectal areas
parasympathetic effect on eyes
constriction of the pupils
increase the curvature of the lens
three things in the accommodation reflex:
pupils constrict
eyes convergence
lens more convex
mr potato head theory
the extraocular muscles are controlled by
CN, III, IV, VI
medial longitudinal fascicules fx:
connects CH, II, IV, VI together on both sides of the brainstem
- a wiring bundle + inner ear
the nickname for the medial longitudinal fascicules are:
a wiring bundle + inner ear
diplopia is
double vision
in misalignment there are two phases:
acute and chronic
in the acute misalignment phase, you get
diplopia
diplopia in the acute misalignment phase does what?
double vision which initially reduces visual acuity?
in the chronic misalignment phase, you get
suppressed vision from 1 eye :
suppressed vision in one eye causes what
loss of depth perception
why is there an increase in curvature for the parasympathetic
the parasympathetic lens bends to keep objects in focus
- makes bigger w/ constriction
what are the two parts of the pupillary light reflex:
direct - eye you shine light in
consenual - ‘along with’ eye w/o light
