08a vision processing overview

Post on 03-Jul-2015

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Visual Signal Processing

Visual receptor

Retina histology

Photoreceptors Rod and Cone

Anatomical Distribution of Rods and Cones

Phototransduction

Phototransduction and electrical conduction

Retina Functional organization

1. Retinal cell types

2. Neural Circuitry of Retina

3. Hyperpolarization

4. Neurotransmitters

5. Electrical synapse with graded conduction

6. Lateral inhibition

7. Bipolar cell depolarization/ hyperpolarization

Lateral inhibition mechanism

Central Projections of Retinal Ganglion Cells

Pupillary reflex

Organization of Visual Cortex

Extrastriate Visual Areas Macaque Monkey

Human Visual Cortex fMRI

Simple Cell

Complex cell

Orientation column of visual cortex

Blobs and Ocular dominance Column

AIT = anterior inferior temporal area; CIT = central inferior temporal area; LIP = lateral intraparietal area; Magno = magnocellular layers of the lateral geniculate nucleus; MST = medial superior temporal area; MT = middle temporal area; Parvo = parvocellular layers of the lateral geniculate nucleus; PIT = posterior inferior temporal area; VIP = ventral intraparietal area.) (Based on Merigan and Maunsell 1993.)

Motion in the visual field

MT lesions in Monkey and Man with altered Motion Perception

Depth of vision

Neuronal basis of stereoscopic vision

Illusion of Edges: V2 in Monkey

Inferior Temporal neuron response to Color & Form

Face and Complex Form Recognition ITC

Color Vision

Cones and Color Vision

Surface reflectance

Surface reflected from blue vase in sunlight and skylight

The reflectance function of a natural surface

L+M

L-M

L+M-S

Receptive field of Primate Ganglion Cells for Color

The Importance of Context in Color Perception

Color blindness

Normal Protanope

Deuteranope Tritanope

Ishihara Chart for Color blindness testing

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