Ganglion cells Bipolar cells LGN Visual Cortex

V1V2V3V4V5V6V7

Dorsal pathway: Where?To post. parietal cortexMOTION (+ motion illusions)

Ventral pathway: What?To inferior temporal cortexColour and form (+ illusory contours)

Overview of Visual Processing

= 4C-alpha, simple cell?

= 4C-beta, complex cell?

light

rods and cones

horizontal cellsbipolar cellsamacrine cells

ganglion cells

(onto optic nerve)

The retina:

Lateral geniculate nucleus of thalamus:

1* visualcortex:

Midget

Amacrine?+?

Parvocellular cellsmajority, smaller receptive fields, slower, colour vision, sustained response

Magnocellular cells larger receptive fields, convergence, faster, more sensitive, detect motion, transient reponse

4 parvocellular layers

2 magnocellular layers

spiny stellate neurons4th layer of sublayer A

spiny stellate neurons,4th layer of sublayer B

LGN (optic radiation)

What?

Where?

http://www.circadian.org/biorhyt.html

http://en.wikipedia.org/wiki/Two-streams_hypothesis

Cortical columnscortical column (somatosensory):a vertical column of the cortical layers that has a near identical receptive field, but each layer corresponds to a different modality.

orientation column: is a vertical column in which each layer displays the same orientational preference for the stimulus, every 1mm a different orientation

ocular dominance:0.5mm wide cortical strips that prefer input from either retina

hypercolumn: 1-2mm^2 cortical column responding to all orientations of a stimulus, both retinae and performing colour analysis of differently sized visual fields

tiger stripe:organisation of ocular dominance columns

pinwheels:organisation of orientation columns

amblyopia: disorder of the visual system resulting from a deficiency in optic information from one eye reaching the cortex, which results in cortical development that makes it impossible to recover the function

http://www.pnas.org/content/102/11/4158/F2.expansion.html

http://en.wikibooks.org/wiki/Consciousness_Studies/The_Neuroscience_Of_Consciousness