visual neuro final cards !!

Question 1

diabetes

Answer 1

haemorrhage
ischemia -> leaky vessels
basement membrane thickness increase
loss of pericytes -> increased vascular perm.
microaneurisms

Question 2

stroke

Answer 2

blood vessel diameter can be a predictor

Question 3

parkinsons

Answer 3

OPL thickening -> a-syn deposits
RNFL thinning and decreased macular thickness

Question 4

alzheimers

Answer 4

b amyloid plaques can be seen using hyperspectral imaging
rnfl thinning bc decreased GCs

Question 5

MS

Answer 5

loss of GCs

Question 6

hypertension

Answer 6

ratio between art : vein thickness alters
art narrowing = increased pressure = squishes veins
blood retinal barrier breakdown

Question 7

pupillary light reflex pathways - dilation

Answer 7

absence of light
sympathetic NS
sphincter muscles relax
dilate for emotion too

Question 8

pupillary light reflex pathways - constriction

Answer 8

presence of light
parasympathetic NS
activate sphincter muscles
constrict for near vision

Question 9

pupillary light reflex pathways - 3 neuron model

Answer 9

1. hypothalamus -> thoracic s.c.
2. thoracic sympathetic trunk -> long ciliary
3. dilator muscle (release NA to a1 rec)

Question 10

horner’s syndrome

Answer 10

pupillary light reflex pathways 3 neuron pathway disrupted
can’t dilate eye
lid droops
no sweating
blood vessel dilation in this area

Question 11

accessory optic system

Answer 11

birds & fish -> main visual area
mammals -> large field motion
optokinesis & vestibular connections
nystagmus = involuntary eye movements

Question 12

accessory optic system - inputs

Answer 12

MT/MST and V1

Question 13

super colliculus

Answer 13

directing eye based on attention (and maintaining gaze on something)
humans -> in cortex
birds -> ventral and dorsal streams
bimodal and tri modal neurons

Question 14

suprachiasmatic nucleus

Answer 14

input from: intrinsically photosensitive GCs
circadian rhythm

Question 15

pulvinar nucleus of the thalamus - input and output

Answer 15

input -> both layers of SC
output -> wide to cortical visual areas & parietal cortex

Question 16

pulvinar role
lesion =?

Answer 16

combine different pieces of information
lesion = facial rec. issues
activation for angry (closed mouth) and surprised facial expressions

Question 17

simple vs complex cells (huber and wiesel)

Answer 17

simple -> small r.f., separate on and off, L4 and 6
complex -> large r.f., overlapping on and off, outside L4

Question 18

issues with hubel and wiesel

Answer 18

1. remove inhibition to striate cell = no orientation sel
2. complex often respond to stimuli simple cells don’t -> so how can complex get input from simple?
3. both complex and hypercomplex can be monosynaptically excited from LGN
4. simple and complex distinction doesn’t apply at low contrast or after adaptation

Question 19

saccades: FEF, PPC, DLPFC

Answer 19

fef: voluntary
ppc: reflex
dlpfc: inhib reflex

Question 20

latency: vor vs okn

Answer 20

okn - 80ms
vor - 7ms

Question 21

endogenous attention can be split into two types - what are they

Answer 21

spatial (attend to road while driving)
feature based (alll red cars in car park)

Question 22

____ rf along ventral steam

Answer 22

increased
v1 v4 teo te

Question 23

when do critical periods end?

Answer 23

1. axonal growth stops = can’t change arbor length
2. synaptic transmission fully matures
3. neuromodulator activity decrease

Question 24

why critical periods?

Answer 24

adapt developing ns to enviro, fine tune and calibrate cells

Question 25

strabismic amblyopia

Answer 25

eye misalignment
double image
image doesn’t fall on fovea

Question 26

anisometropic amblyopia

Answer 26

different glasses prescription between the two eyes -> dissimilar for the brain to connect

Question 27

stimulus deprivation amblyopia

Answer 27

occluded optical axis
something blocking light from getting to retina

Question 28

refractive error amblyopia

Answer 28

can be fixed w glasses

Question 29

neural basis for amblyopia

Answer 29

brain prefers one eye, this can lead to cortical changes -> loss of OD columns for that eye

Question 30

levi and hess drama !!!

Answer 30

hess -> neural dissarray (wrong info given to next step)
levi -> undersampling to incorrect sampling (rf size increase -> start acting like peripheral cells)

then daminin came in and said its the same thing

then levi revised saying neural noise impacts effectiveness of sampling

Question 31

blindsight

Answer 31

MT (and pulvinar) bypasses V1 so even if someone has a full V1 lesion and cant see they can still go through a maze