Exam 2

Question 1

what is central sensitization

Answer 1

excessive response of a central neuron (like pain) due to constant simulation that ends up changing the neuronal structure to cause skewed perception of what it actually is

Question 2

what does spatial summation of stimulus tell u

Answer 2

how big it is (how many receptive fields are stimulated at the same time)

Question 3

what does the temporal summation of stimulus tell u?

Answer 3

is it moving? how many times has it touched the same or diff. fields?

Question 4

how do u fix an overactive or hypersensitive sensory system?

Answer 4

habituation, stim it over and over and over and over again until it gets used to it

Question 5

what is tactile defensiveness?

Answer 5

low touch thresholds (alex)

Question 6

what is hyperalgesia

Answer 6

low low pain threshold

Question 7

how do u fix an underactive sensory system

Answer 7

stim it all the time to increase neuronal response

Question 8

what does a primary sensory cortex do?

Answer 8

registers that a receptor has been activated and Maps where it is happening

Question 9

what does a secondary sensory cortex do?

Answer 9

processes info from that sensation alone, patterns of activity and anticipation of activity

Question 10

what does a sensory association cortex do?

Answer 10

integrates related info and activity from diff. sensory systems to get the whole picture

Question 11

what does a gamma motor neuron do?

Answer 11

changes the length of the mm spindles so that it resets it to be the same length as the mm fiber, this way the spindle knows how much more length it has to give

Question 12

what does a golgi tendon organ do?

Answer 12

responds to slow tension (stretch)

Question 13

what does a mm spindle respond to?

Answer 13

quick stretch

Question 14

what is a rhomberg test for?

Answer 14

balance

Question 15

what does an intention tremor and dysdiadochokinesis point to?

Answer 15

cerebellar dysfunction

Question 16

What area is Wernicke’s area? When is it activated?

Answer 16

22- only activated when it is Language being heard

Question 17

Broca’s area is what? what does it do?

Answer 17

area 45, speech production

Question 18

What is the CN V reflex

Answer 18

reflex to protect our ears agains loud low frequency sounds, it inhibits teh tensor tympani mm wish then inhibits the malleus from moving as much and causing damage

Question 19

what is the CN VII reflex?

Answer 19

facial N reflex, protects against loud high freq. sounds, it inhibits the stapedius mm from activating the stapes

Question 20

what is the olivocochlear pathway

Answer 20

sound comes in via CN VIII–>inf. olivary nucleus–>the inf. olivary nucleus sends a feedback message right back to the cochlea via CN VIII again telling the cochlea to adjust the sensitivity of the haircells

Question 21

cones see ___________, rods see____________

Answer 21

cones see color, rods= black and white

Question 22

what does night vision

Answer 22

rods

Question 23

what is the optic disc

Answer 23

the spot in the eye where the optic N and blood VV enter the eye, no rods or cones= no visual perception there

Question 24

what causes glaucoma

Answer 24

aqueous humor can’t drain properly so it builds up and creates pressure in the eye which transers from the aqueous humor in the anterior chamber to the vitreous humor in the posterior chamber and crushes the blood vv on the back of the eye in the retina so cells die and pts become blind.

Question 25

when do ciliary mm do what?

Answer 25

they pull tight and the lens gets round for close up vision, then they relax and the lens gets more oblong again for far away vision

Question 26

whats macular degenertion

Answer 26

can’t see the center of a picture. disease of the macula, a very densely cone packed area of the retina

Question 27

diabetic retinopathy

Answer 27

looking thru dirt covered lenses, imbalance of blood glucose levels stimulates growth hormone with causes inappropriate blood vv growth in the retina. When the blood vv grow enough they begin to peel up off the retina. this tears the retina and causes lesions in the visual field. the blood vv are leaky also, which causes more problems for the retina.

Question 28

presbyopia

Answer 28

aging eyes, lens becomes less elastic and ppl require corrective lenses to focus close up (reading glasses)

Question 29

myopia

Answer 29

blurry vision, weak ciliary mm or misshapen lens

Question 30

what is legal blindnessq

Answer 30

20/250

Question 31

dry cornea is a common symptom of what systemic disease?

Answer 31

RA

Question 32

retinitis pigmentosa

Answer 32

tunnel vision, loose photoreceptors in periphery of retina

Question 33

visual symptoms that are emergencies?

Answer 33

seeing sparks= tearing away of retina
red velvet curtain= detaching retina
diploplia= CNS not working right

Question 34

optic N lesion–>one eye

Answer 34

lose one entire eye, can see everything except visual field in the far side of the damaged eye. ex. if its the R eye thats impaired i can see everything except the far R side

Question 35

optic tract lesion–>contralateral homonymous hemianopsia

Answer 35

if the R optic tract is lost, u lose the temporal fibers from that eye-the R eye (which sees towards midline) and u lose the nasal fibers from the opp eye- the L eye (which see out towards L periphery) so u lose half the field of each eye… this is contralateral homonymous hemianopsia

Question 36

optic chiasm lesion–>tunnel vision

Answer 36

tunnel vision, u lose nasal fibers from both eyes, nasal fibers look towards the periphery so u lose that peripheral vision. U still have both sides temporal fibers which look towards the midline so thats the only visual field u get.

Question 37

what visual world do the R optic raidations see?

Answer 37

the L visual world, the R optic radiations get info from the R lateral geniculate bodies about the L visual world

Question 38

what visual world do the L optic radiations see?

Answer 38

the R visual world, the L optic radiations get info from the L lateral geniculate bodies about the R visual world

Question 39

Meyer’s loop?

Answer 39

takes info about the upper and lower halves of the visual space to the opposite cortex, upside down and opposite

Question 40

area 17

Answer 40

registers visual info

Question 41

areas 18&19

Answer 41

secondary visual cortex, recognizes patterns, shapes, color and motion

Question 42

Areas 39 &40

Answer 42

integrates info from several different sensory systems to complete the whole picture

Question 43

what fibers alter your periphy that something is there?

Answer 43

tecto-cortical fibers

Question 44

what makes pie in the sky visual dysfunction, a person might say they didn’t see the stoplight

Answer 44

damage in temporal lobe->loss of meyer’s loop, lower R optic radiations= upper L periphery loss and upper R midline loss this is called contralateral homonymous superior quadrantoanopsia

Question 45

object agnosia

Answer 45

nothing to do with visual probs, can’t recognize it without looking at it–>if i stick my hand in my purse i know its got a handle and bristles and is shaped like a paddle but i don’t know its my brush until i look at it

Question 46

prospagnosia

Answer 46

face blindness, affects the fusiform gyrus

Question 47

where is the damage if a person keeps tripping over things on the floor bc they don’t see them?

Answer 47

parietal lobe, upper R optic radiation damage. lower L periphery loss and lower R midline loss–> contralateral homonymous inferior quadrantanopsia

Question 48

what is damaged if a person has complete unilateral neglect?

Answer 48

occipital lobe, lesion thruoough upper and lower optic radiations of the same side. so total L periphery loss and total R midline loss= left side loss (neglect)