Components of the visual system. The individual neuron.

Slides:

Advertisements

Similar presentations

What do we know about Primary Visual Cortex (V1)

Advertisements

Central Visual Processes. Anthony J Greene2 Central Visual Pathways I.Primary Visual Cortex Receptive Field Columns Hypercolumns II.Spatial Frequency.

Visual Attention Attention is the ability to select objects of interest from the surrounding environment A reliable measure of attention is eye movement.

What is vision Aristotle - vision is knowing what is where by looking.

1.Exams due 9am 16 th. (grades due 10am 19 th ) 2.Describe the organization of visual signals in extra-striate visual cortex and the specialization of.

PSYC 330: Perception Seeing in Color PSYC 330: Perception

Perception of Stimuli Stephen Taylor.

Chapter 6 The Visual System

2002/01/21PSCY , Term 2, Copyright Jason Harrison, The Brain from retina to extrastriate cortex.

Neuron Neurons Purkinje cells from cerebellum, dendrites showing calcium concentration.

Question Examples If you were a neurosurgeon and you needed to take out part of the cortex of a patient, which technique would you use to identify the.

Blue= rods Green = Cones Pathways from the Retina In the brain, retinal ganglion axons travel to… –the hypothalamus: control bodily rhythms.

1 Biological Neural Networks Example: The Visual System.

Exam 1 week from today in class assortment of question types including written answers.

Visual Processing Structure of the Retina Lateral Inhibition Receptive Fields.

Higher Processing of Visual Information: Lecture I --- April 2, 2007 by Mu-ming Poo 1.Overview of the Mammalian Visual System 2.Structure of Lateral Geniculate.

1 Retinal Circuit and Processing March 23, 2007 Mu-ming Poo Overview of the retinal circuit Receptive field (RF) of retinal ganglion cells (RGC) Neural.

The Human Visual System Short Overview. Terms: LGN, cortex, primary visual cortex, V1.

Levels in Computational Neuroscience Reasonably good understanding (for our purposes!) Poor understanding Poorer understanding Very poorer understanding.

Visual Sensation & Perception How do we see?. Structure of the eye.

Chapter 10 The Central Visual System. Introduction Neurons in the visual system –Neural processing results in perception Parallel pathway serving conscious.

How does the mind process all the information it receives?

Color vision Different cone photoreceptors have opsin molecules which are differentially sensitive to certain wavelengths of light – these are the physical.

The Eye. A Model for Sensing  Three components: Stimulus detection – a specialized sensory neuron Reception – where neurons receive information from.

Human Sensing: The eye and visual processing Physiology and Function Martin Jagersand.

The Human Visual System Vision Class The main topics covered here were: photoreceptors and ganglion cells in the retina. The photoreceptors are.

Visual Surveillance Chip. 1. Visual Change Detection 2. Photoreceptors and change detection 3. superior colliculus / optic tectum Visual Surveillance.

The Human Visual System Vonikakis Vasilios, Antonios Gasteratos Democritus University of Thrace

Ch 31 Sensation & Perception Ch. 3: Vision © Takashi Yamauchi (Dept. of Psychology, Texas A&M University) Main topics –convergence –Inhibition, lateral.

Chapter 10 The Central Visual System. Introduction Neurons in the visual system –Neural processing results in perception Parallel pathway serving conscious.

Higher Processing of Visual Information: Lecture II

ניורוביולוגיה ומדעי המח Introduction to Neurobiology Introduction to Sensory Systems The retina “From Neuron to Brain” Chapter 19: Transduction.

The visual system Lecture 1: Structure of the eye

Laurent Itti: CS599 – Computational Architectures in Biological Vision, USC Lecture 5: Introduction to Vision 2 1 Computational Architectures in.

Neuroscience: Exploring the Brain, 3e

Copyright © 2007 Wolters Kluwer Health | Lippincott Williams & Wilkins Neuroscience: Exploring the Brain, 3e Chapter 10: The Central Visual System.

Major transformations of the light signal in the retina: 1.Temporal filtering – visual response slower than input signal. 2. Spatial filtering – local.

The Visual System General plan for visual system material: How the visual input is received and transduced at the retina by photoreceptors (rods and cones)

1 Computational Vision CSCI 363, Fall 2012 Lecture 3 Neurons Central Visual Pathways See Reading Assignment on "Assignments page"

THE VISUAL SYSTEM: EYE TO CORTEX Outline 1. The Eyes a. Structure b. Accommodation c. Binocular Disparity 2. The Retina a. Structure b. Completion c. Cone.

Slide 1 Neuroscience: Exploring the Brain, 3rd Ed, Bear, Connors, and Paradiso Copyright © 2007 Lippincott Williams & Wilkins Bear: Neuroscience: Exploring.

Occipital Lobe Videos: –Brain modules 8,9,10, 11 –Consciousness- Blindsight.

The Visual Pathway Sensory Systems What is a Sensory System? –Window to the physical energies of the external environment. –Gives rise to sensory perceptions.

Ch 31 Sensation & Perception Ch. 3: Vision © Takashi Yamauchi (Dept. of Psychology, Texas A&M University) Main topics –convergence –Inhibition, lateral.

1 Computational Vision CSCI 363, Fall 2012 Lecture 5 The Retina.

Human vision Jitendra Malik U.C. Berkeley. Visual Areas.

Sensation & Perception Ch. 1-3: Review © Takashi Yamauchi (Dept. of Psychology, Texas A&M University)

1 Perception and VR MONT 104S, Fall 2008 Lecture 2 The Eye.

1B50 – Visual System Daniel J Hulme. Errata Phylogenetic – genetic history of the species Ontogenetic – experience of the individual It was Kepler who.

1 RETINA n Review its structure and function. 2 TRANSDUCTION n Mechanism:dark current->light response n Amplification n Adaptation/recovery n Transmission.

Understanding Psychophysics: Spatial Frequency & Contrast

Outline Of Today’s Discussion 1.LGN Projections & Color Opponency 2.Primary Visual Cortex: Structure 3.Primary Visual Cortex: Individual Cells.

Sensory Neural Systems 5 February 2008 Rachel L. León

The Human Visual System Background on Vision Human vision – the best system around Deep network models.

Perception of stimuli Option A.3. Receptors detect changes in the environment. List and describe the types of specialized receptors in humans. a. Mechanoreceptors-

1 Computational Vision CSCI 363, Fall 2012 Lecture 32 Biological Heading, Color.

Vision is created by utilizing two properties of light, energy(intensity) and frequency (wavelength) of stimulus.

1 Perception and VR MONT 104S, Spring 2008 Lecture 3 Central Visual Pathways.

Biological Image Processing Physiology and Function C428/615 Martin Jagersand With illustrations from: Tutis Vilis Talia Konkle and others as cited.

Processing visual information - pathways

Retinal Circuit and Processing

Neuroscience: Exploring the Brain, 3e

BY DR. MUDASSAR ALI ROOMI (MBBS, M. Phil.)

The trichromatic hypothesis of color perception:

Neuron Neurons Purkinje cells from cerebellum, dendrites showing calcium concentration.

Early Processing in Biological Vision

Smoothing the intensities

Physiology of Photoreceptors Vertebrate photoreceptors hyperpolarize and produce graded potentials Photoreceptors use glutamate as transmitter.

Perception: Structures

David J Calkins, Peter Sterling Neuron

Presentation transcript:

Components of the visual system

The individual neuron

Neuron

Neurons Purkinje cells from cerebellum, dendrites showing calcium concentration

Synaptic connection

Synapse

The Eye The main aspects are the photoreceptors, which is the input layer, and the ganglion cells, the output layer to the brain

Eye

Neural circuitry of the retina

Receptors Density - Fovea

Photoreceptors

Visual receptor types

Spectral sensitivity

Color Mixing

Dynamic Range

Center-surround Receptive Fields Modified from PSY280F

Edge-detection by zero-crossings Some theory, and the relation to ganglion cells.

Edge Detection by Z.C. Peak in f’(x) z.c. in f’’(x) Noise: Asin(wx) > -w 2 cos(wx) Convolve with a Gaussian (optimal) d 2 /dx 2 (G*f) = d 2 /dx 2 (G) * f In 2-D: d 2 /dx 2 + d 2 /dy 2

Edge Detection by Z.C.

Z.C. at Two Scales

Wheel Edges 4 Resolutions

LGN Layers

The Cortex The main topics are: area V1 in some details, response properties of cells in V1, how they are organized in the area. General properties of higher level visual areas.

Physiological Recording

Orientation Selectivity

V1: Direction selectivity Modified from PSY280F

End-stopped cell

Simple Cells

Visual Areas

Bi-directional Computation

Stimuli tested in V2, V4

From: Tanaka, 1996 Columnar modules of region TE

fMRI Magnet

fMRI Activation Slice

fMRI Activation