Neuro L7

Question 1

How many odors can humans detect?

Answer 1

10,000

Question 2

Olfactory epithelium
Laterallity
Contents

Answer 2

Bilateral
3 million receptor cells
Bowman’s gland ducts
Sensory endings from CN V1 (irritants)

Question 3

What is unusual about olfactory receptors

Answer 3

Lifespan of neuron is 1-2 months

Question 4

Axons from olfactory receptors

Description

Answer 4

Among the thinnest and slowest

Question 5

Axons from olfactory receptors collect into a series of bundles called

Answer 5

Olfactoy fila

Question 6

Olfactory fila make up

Answer 6

CNI

Question 7

Olfactory bulb and tract develops as an outgrowth of

Answer 7

Telencephalon

Question 8

Each olfactory receptor sends an axon to

Answer 8

one glomerulus of a mitral cell

Question 9

Collateral to anterior olfactory nucleus are thought to

Answer 9

regulate sensitivity of olfactory bulb

Question 10

Pyriform area (3)

Answer 10

uncus
entorhinal area
limen insula

Question 11

Lateral olfactory stria (primary olfactory area)

Answer 11

Cortex over amygdala and pyriform area

Pyriform area

Question 12

Medial olfactory stria

Answer 12

Medial frontal lobe surface

Question 13

Medial olfactory stria function

Answer 13

emotional response to smell

Question 14

Olfactory association cortex

location

Answer 14

Orbital surface of frontal lobe and anterior insula

Question 15

Olfactory information is sent to

Answer 15

Hypothalamus
orbital cortex
amygdala (Uncus)
Thalamus
hippocampus

Question 16

What is special about olfactory to the cortex

Answer 16

It does not stop in thalamus

Question 17

Remembering smells

Answer 17

Projection from thalamus to association cortex????

Question 18

Importance of fovea

Answer 18

eye muscles make sure fovea is on focal point of vision

Question 19

Lens accounts for ____ of eyes refractive power

Major role

Answer 19

1/3

focusing for near/far objects

Question 20

Most refraction is in

Answer 20

air-water interface at corneal surface

Question 21

Iris

function

Answer 21

brightness and quality

Question 22

Pupillary sphincter vs dilator
Strength
arrangement

Answer 22

Pupillary sphincter:
Stronger
Encircles pupil
Pupillary dilator:
Weaker
Radiating spokes

Question 23

Rhodopsin

Answer 23

low acuity, monochromatic in dim light

Question 24

Cone pigments

Answer 24

high acuity, color vision, need a lot of light

Question 25

Outer vs inner segment of rods and cones

Answer 25

Outer: contain visual pigment Inner: mitochondria, synthesize pigment

Question 26

Most axons from optic tract travel to

Answer 26

Lateral geniculate nucleus (Thalamic relay for vision) | Then to primary visual cortex in calcarin suclus

Question 27

LGN structure

Answer 27

6 layer 146 contralateral 235 ipsilateral

Question 28

LGN projections in pirmary visual cortex

Answer 28

inferior visual fields are most superior radiations | Superior visual fields are most inferior radiations

Question 29

Other destinations for visual information

Answer 29

superior colliculus | Hypothalamus

Question 30

Hypothalamus function with visual information

Answer 30

Suprachiasmatic nucleus get direct input | Master timer of circadian rhythm

Question 31

Quadrantanopia

Answer 31

loss of quarter of visual field

Question 32

Damage to chiasm causes ____ deficit

Answer 32

heteronymous

Question 33

Damage to optic tract causes deficit

Answer 33

Homonymous

Question 34

Oculomotor brain stem location

Answer 34

rostral midbrain

Question 35

Trochlear brain stem location

Answer 35

Caudal midbrain

Question 36

Abducens bran stem location

Answer 36

Caudal pons

Question 37

Pupillary light relfex

Answer 37

light Retinal ganglion cells --> pretectal nuclei Pretectal nuclei--> Edinger Westfal nuclei EWN-->pregang parasymp-->ciliary ganglion Postgang-->sphincter pupillae of iris

Question 38

To view an object up close

Answer 38

Ciliary muscles contract Suspensory ligaments relax Lens bulges

Question 39

CNIII injury | Affected eye

Answer 39

``` Ipsilateral Down and out because medial rectus is weak and lateral rectus is unopposed Vertical impaired b/c weak superior and inferior recti inferior oblique Pupil does not constrict w/ light ```

Question 40

What is unique about the Trochlear nerve pathway

Answer 40

exit brainstem on dorsal surface

Question 41

What direction does superior oblique move the eye?

Answer 41

Down and laterally

Question 42

CNIV injury

Answer 42

affected eye point up head tilts away from lesion Diplopia when going down stairs or reading

Question 43

Facial colliculus

Answer 43

VI nucleus and internal genu

Question 44

CNIII CNIV CNVI eye muscles

Answer 44

``` III: Superior rectus Inferior rectus Medial rectus Inferior oblique IV: Superior oblique VI: Lateral rectus ```

Question 45

Susceptibility of CNVI

Answer 45

long intracranial course-->susceptible to increased intracranial pressure-->Bilateral palsy

Question 46

Injury to VI nucleus symptoms

Answer 46

Ipsilateral medial strabismus lateral gaze paralysis

Question 47

Three main types of eye movement

Answer 47

Scanning: high speed from one target to another Tracking: Smooth persuit Compensation: gaze held on object during head movement

Question 48

Gaze centers location

Answer 48

Reticular formation (midbrain and pons)

Question 49

Paramedian pontine reticular formation

Answer 49

horizontal saccades | Each pulls eye ipsilaterally

Question 50

Rostral interstitial nuclei of MLF (riMLF)

Answer 50

Upward saccades

Question 51

Left PPRF activated by which field of vision

Answer 51

right frontal eye field