vision

Question 1

cones

Answer 1

see color and acuity

Question 2

were do you find the most cones

Answer 2

fovea

Question 3

Rods

Answer 3

color-blind; better for motion

Question 4

photoreceptors

Answer 4

rods and cones

Question 5

Fovea

Answer 5

‘best vision’ for acuity and color

Goal of lens of eye, eye & headmovement, and brain guidance is to getthe light to focus on the fovea… so yousee best! only cones in the fovea

Question 6

Extra fovea

Answer 6

all cell types includingcones and rods.
more rods then cones

Question 7

Extra fovea

Answer 7

all cell types includingcones and rods.
more rods then cones

Question 8

Pathway from retina to visual cortex:

Answer 8

Retina(ganglion cells are theneurons of origin)
Optic nerve
Optic chiasm (crossing of some axons)
Optic tract
Lateral geniculate nucleus (thalamus), LGN
Through the parietal andtemporal cortex as optic radiations
Visual cortex

Question 9

the visual field

Answer 9

each eye seen 2/3 of the visual field, there is an overlap in the center

Question 10

Nasal retinal information​ goes where

Answer 10

crosses at optic chiasm to go to contralateral V1

lateral portions of each visual fields - nearest nose/medial

Question 11

Temporal retinal information goes where

Answer 11

does not cross at chiasm, continues ipsilaterally to V1

medial portion of each visual field - near temporal bone/lateral

Question 12

Left visual cortex, receives retinalafferent from where

Answer 12

axons with information about theright (opposite) half of thevisual field ofeach eye

Question 13

peripheral aspects of the visual field is seen by what

Answer 13

about aquarter of the visual field is seen byone eye only.

Question 14

Visual context

Answer 14

the visual signal from the background of the scene

Question 15

Visual experience/learning changes in neural circuits

Answer 15

experience-dependent (e.g.a lifeguard surveys a crowded pool andsees features of the person in trouble; PT in busy gym recognizes thepatient in pre-distress)

Question 16

Cognitive influences of attention, expectation, task-dependent (even perceptual task):

Answer 16

hockey player skating up theice, finds the potential open path to the goal; person walking dogs inthe pre-dawn attentive to potential harm – wild animal, stranger,vehicles out of control

Question 17

Neurons in the LGN receptive fields

Answer 17

Neurons in the LGN have centersurround receptive fields

These neurons with surround RF will enhance the light when it on the RF and depress some of the weaker light responses

They depress the weaker unit and support the brighter inputs

Question 18

Visual cortex (V1) two type of cells

Answer 18

simple cells and complex cells

Question 19

simple cells in V1

Answer 19

on/off: Neuronshave orientation sensitivity;respond to specific light orientations oflines/edges

They are tuned to light in a very specific orientation

Question 20

Complexcells in V1

Answer 20

respond to continuousbar of light in a specific orientationanywhere in receptive field; integratesimple cell content to form lines andedges, with contours/textures

Question 21

V1 - visual cortex preception of what

Answer 21

color and motion

Question 22

Preconscious path for quick action

Answer 22

‘M’cells, magnocellular visual path

Rapid transmission back to the visual cortex

retina to visual cortex via thelateral geniculate nucleus(LGN).

‘Where & how’ – it over there for better move now

Question 23

Conscious slower path for integratedperception and thought

Answer 23

P’ cells,parvicellular visual path

‘What’

Question 24

dorsal stream for action

Answer 24

Visually-guided reaching

‘Visually-informed grasping’

Question 25

‘Visually-informed grasping’

Answer 25

Translates visual info about object properties into successful grasping Extrastriate cortex to premotor ventral (PMv) via anterior intra-parietal area

Question 26

‘Visually-guided reaching’

Answer 26

Extrastriate to dorsal premotor (PMd) via medial dorsal- and medial intra-parietal areas Translates visual info of object location to reaching direction

Question 27

ventral stream for

Answer 27

object recognition What is that object, I have seen that face before

Question 28

Inferior temporal cortex codes what

Answer 28

codes complex, higher order integrated information, e.g. faces, hands

Question 29

he ventral stream has lot of connects with whta?

Answer 29

Has a lot of connection with the prefrontal cortex

Question 30

Posterior parietal cortex (PP) 

Answer 30

Functions in recognition of self, relative to world: Internal representation of body Perception of self relative to the world: our actions vs their actions

Question 31

Posterior parietal cortex (PP)  neuron RF

Answer 31

complex

Question 32

Posterior parietal cortex (PP) lesion

Answer 32

Lesions associated with spatiotemporal disorganized reach and grasp; gaze disorders; disorientation; constructional apraxia (put on a sweater ...)

Question 33

Prefrontal cortex (PF) (+premotor, PM) 

Answer 33

Motor planning, judgement Select appropriate, suppress inappropriate behavior for current conditions Provides control and flexibility in behavior

Question 34

depth perception needs what cues

Answer 34

Both binocular and monocular cues

Question 35

binocular disparity neurons are active when

Answer 35

the image in view is focused on slightly different parts of the retinas of each eye.

Question 36

Attention

Answer 36

looking for something, expectation, what to attend to a specific stimulus

Question 37

Top down

Answer 37

attention of your intent Looking for someone in a red shirt

Question 38

Bottom or mid- up

Answer 38

what your gaze caught – eye muscle proprioceptors to visual cortex via thalamus …

Question 39

Two types of eye movements

Answer 39

Gaze stabilization Direction of gaze

Question 40

Gaze stabilization

Answer 40

: keeps image stable when our head moves VOR 

Question 41

Direction of gaze

Answer 41

attend to visual targets: How do we explore our environment quickly and efficiently? 

Question 42

Direction of gaze two type

Answer 42

saccades smooth pursuit

Question 43

saccades

Answer 43

voluntary or reflexive, shift the fovea rapidly to a new visual target Reading- we do not read left to right, we looking at different parts of the sentence to put it together Redirects center of sight, allows us to scan environment quickly

Question 44

smooth pursuit

Answer 44

Following a moving target Keep target on fovea Match eye speed to target speed Much slower speed (maximum 100 degrees per second) 

Question 45

what muscle do smooth pursuit and saccades use

Answer 45

But, they both use the six extraocular muscles/agonist – antagonist pairs​

Question 46

Medial and lateral recti move the eye what direcction

Answer 46

horizontally​

Question 47

Superior rectus and inferior oblique move the eye

Answer 47

elevate eye

Question 48

inferior rectus and superior oblique move the eye

Answer 48

depress it ​

Question 49

Conjugate gaze

Answer 49

– moving two eyes together

Question 50

Triggered (reflexive) saccades

Answer 50

something moves in visual field [detect]

Question 51

Attention (voluntary) saccades:

Answer 51

visual attention to something in visual field [find]

Question 52

Attention (voluntary) saccades pathway

Answer 52

Input from frontal eye fields, posterior parietal cortex to superior colliculus to pontine brainstem centers for gaze motor control

Question 53

basal ganglia role on saccades

Answer 53

input to superior colliculus inhibit superior colliculus and suppress saccades.  (consider: performing a well-learned motor skill, not interested in distraction of detect or find saccade eye movements) When you are doing a well learned skill the BG stop saccades – stopping distractions

Question 54

smooth pursiut pathway

Answer 54

Information about object movement from visual association cortex > middle temporal cortex > frontal eye fields projected > pontine nuclei > the cerebellum and vestibular nuclei and onto pontine centers for gaze movement control.

Question 55

Tau

Answer 55

Time to contact When a n object is moving close to you it is expanding on the retina Very powerful predictive information, feedforward

Question 56

Optical Flow

Answer 56

the visual information that is streaming past us