Visual Pathways

Front 1

Layers of LGN

Back 1

Magnocellular (2)
Parvocellular (4)
koniocellular interposed between principal layers

Front 2

Properties of LGN neurons

Back 2

-functionally similar to retinal ganglion cells
-moncular
-concentric receptive fields

Front 3

mLGN cells

Back 3

-process M retinal ganglion cell inputs
-large center-surround receptive fields
-color insensitive
-sensitive to movement of visual stimuli

Front 4

pLGN cells

Back 4

-process P retinal ganglion cell inputs
-small center surround receptive fields
-color sensitive
-detect contrasts that form basis of shape/form discrimination

Front 5

kLGN

Back 5

-process P retinal ganglion cells
-behave lie P RGCs
-smallest concentric receptive fields
-stronger color sensitivity that P RGCs

Front 6

Striate cortex

Back 6

includes calcarine cortex and extends around occipital pole to include lateral aspect of caudal occipital lobe

Front 7

LGN neurons......

Back 7

send their axons in the internal capsule to the occipital lobe where they terminate in the striate cortex

Front 8

Path of LGN axons in Sublenticular segment

Back 8

form Meyer's loop, travel up to the inferior bank of striate cortex and terminate (superior visual field)

Front 9

Path of LGN axons in Retrolenticular segment

Back 9

pass superiorly t hrough the parietal lobe to end in the superior bank of striate cortex (inferior visual field)

Front 10

V1 Blob Cells

Back 10

resemble kLGN neurons, color sensitive, monocular, small concentric receptive fields, found in clusters or "blobs," special target of kLGN axon terminals, color processing cells of V1

Front 11

V1 Interblob Cells

Back 11

-binocular
-NOT color sensitive
-elongated receptive fields
-found around the V1 blob cells
-ocular dominance
-orientation specificity

Front 12

Location specific V1 interblob cells

Back 12

-p-stream info
-reponsds best when the stimulus is in a specific location of the receptive field (location specificity)
-poor response to movement
-shape/form processing cells and location processing cells of v1

Front 13

Movement sensitive v1 interblob cells

Back 13

-respond best to moving stimuli with no preference for direction of movement

Front 14

Direction specific V1 interblob cells

Back 14

-preference for movement in a particular direction
-M stream info
-detects object movement and direction/velocity
"motion detectors"

Front 15

Which is weaker: long range connection or short range connections?

Back 15

long range connections--exclusively excitatory and tend to connect cortical columns that encode similar features., mediate contextual interactions

Front 16

What is the locus of mid-level vision?

Back 16

Extrastriate cortex

Front 17

What is included in the extrastriate cortex/

Back 17

all of the occiptial lobe areas surrounding the primary visual cortex

Front 18

What modulates the neurons in the extrastriate visual cortex?

Back 18

extraretinal factors such as attention or memory

Front 19

What does damage to the extrastriate cortex cause?

Back 19

higher order visual perceptual deficits including failure to recognize objects, colors, and or movement of objects

Front 20

What sends projections to the extrastriate cortex?

Back 20

V1 primary visual corrtex (info about color, shape/form, location and motion

Front 21

What are the boundaries of the visual association cortex?

Back 21

extends anteriorly from the extrastriate cortex to encompass adjacent areas of the posterior parietal lobe and much of the posterior temporal lobe

Front 22

Wht does the visual association cortex receive input from?

Back 22

via extrastriate cortex

Front 23

Dorsal Stream Properties

Back 23

-parietal assoc cortex, superior and middle temporal visual assoc cortex
-binocular receptive fields
-process P channel info about object location
-process M channel info about object movement

Front 24

What are dorsal stream neurons responsible for?

Back 24

Our sense of:
-spatial orientation
-binocular fusion/depth perception
-location, direction of motion and velocityof objects in space

Front 25

Ventral stream properties

Back 25

-neurons in inferior temporal visual assoc cortex
-process p channel info about object color and form

Front 26

Ventral stream is responsible for.....

Back 26

Our abilities to
-recognize objects and color
-learn and rememberf visual objects
-processes info about the "what" of visual stimulus
-damage results in perception, attention, and learning/memory deficits

Front 27

What kind of information do the optic radiation fibers traveling the most direct course carry?

Back 27

info about the central visual field

Front 28

What do sublenticular optic radiations carry?

Back 28

info abou superior hemifield

Front 29

What do retrolenticular optic radiations carry?

Back 29

info about inferior hemifield