Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Photoreceptors and Visual Pathways

Photoreceptors and Visual Pathways

At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category, whereas...

Color Vision

Color Vision

Color perception begins in the retina, the light-sensitive layer at the back of the eye. Two main theories explain how colors are seen: the trichromatic theory and the opponent-process theory. The trichromatic theory, proposed by Thomas Young in 1802 and extended by Hermann von Helmholtz in 1852, suggests that color vision is based on three types of cone receptors in the retina. These cones are sensitive to different but overlapping ranges of wavelengths corresponding to red, blue, and green.

Anatomy of the Eyeball

Anatomy of the Eyeball

The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle layer, the vascular tunic,...

Vision

Vision

Vision is the result of light being detected and transduced into neural signals by the retina of the eye. This information is then further analyzed and interpreted by the brain. First, light enters the front of the eye and is focused by the cornea and lens onto the retina—a thin sheet of neural tissue lining the back of the eye. Because of refraction through the convex lens of the eye, images are projected onto the retina upside-down and reversed.

Visual System

Visual System

Light enters the eye through the cornea, a transparent, dome-shaped surface covering the surface of the eyeball that helps to direct and focus incoming light. This light is then channeled toward the pupil, an adjustable opening whose size is controlled by the iris. The iris, a pigmented muscle, regulates the amount of light entering the eye by contracting or dilating the pupil, thereby ensuring optimal light levels for clear vision.
Once through the pupil, the light passes through the lens, a...

Visual Agnosia

Visual Agnosia

Visual agnosia is a condition characterized by the inability to recognize visually presented objects despite having normal vision. For instance, a person with visual agnosia can describe the shape and color of an object but cannot identify or name it. This impairment does not affect their visual field, acuity, color vision, brightness discrimination, language, or memory. An example of this condition in a social setting is someone at a dinner party asking for "that silver thing with a round end"...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Enzymatic antioxidants in erythrocytes following heavy metal exposure: possible role in early diagnosis of poisoning.

Bulletin of environmental contamination and toxicology·1997

Same author

The effects of midazolam and flumazenil on psychomotor function.

Journal of clinical anesthesia·1997

Same author

Adverse drug reactions from birth to early childhood.

Pediatric clinics of North America·1997

Same author

Value of radiography in diagnosing complications of cardioverter defibrillators implanted without thoracotomy in 437 patients.

AJR. American journal of roentgenology·1997

Same author

Secondary distal renal tubular acidosis in association with urological abnormalities.

Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association·1997

Same author

Role of preoperative donor-specific transfusion and cyclosporine in haplo-identical living related renal transplant recipients.

Nephron·1997

Search research articles

Related Experiment Video

Updated: Jun 2, 2026

Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography

Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography

Published on: August 11, 2016

Structural and functional correlates in color vision deficiency.

A Gupta¹, G Laxmi, M G Nittala

¹Shri Bhagwan Mahavir Vitreoretinal Services, Sankara Nethralaya, Chennai, Tamil Nadu, India. guptaaditi_dr@yahoo.com

Eye (London, England)

|April 16, 2011

Summary

This summary is machine-generated.

Congenital red-green color vision deficiency (CVD) shows no major retinal layer abnormalities on SD-OCT, though a narrower foveal pit was observed. Retinal sensitivity remained similar in patients and controls.

More Related Videos

Visualizing Visual Adaptation

Visualizing Visual Adaptation

Published on: April 24, 2017

A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss

A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss

Published on: April 11, 2025

Related Experiment Videos

Last Updated: Jun 2, 2026

Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography

Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography

Published on: August 11, 2016

Visualizing Visual Adaptation

Visualizing Visual Adaptation

Published on: April 24, 2017

A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss

A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss

Published on: April 11, 2025

Area of Science:

Ophthalmology
Vision Science
Medical Imaging

Background:

Congenital red-green color vision deficiency (CVD) affects approximately 8% of males.
Understanding the underlying retinal structure in CVD is crucial for diagnosis and management.
Spectral domain optical coherence tomography (SD-OCT) offers high-resolution cross-sectional imaging of the retina.

Purpose of the Study:

To evaluate photoreceptor integrity in congenital red-green CVD using SD-OCT.
To measure retinal sensitivity in individuals with congenital red-green CVD.
To compare retinal structure and sensitivity between CVD patients and healthy controls.

Main Methods:

SD-OCT and microperimetry were used to examine 7 patients with congenital red-green CVD and 7 controls.
Radial macular scans were acquired, measuring retinal layer thickness at the foveal center and along radial lines.
Retinal and foveal sensitivity were assessed, and data were compared using the Mann-Whitney U-test.

Main Results:

SD-OCT revealed normal retinal thickness, photoreceptor layer thickness, outer nuclear layer thickness, and outer/inner segment vertical thickness.
A significantly reduced OS horizontal diameter was noted in the left eyes of CVD patients compared to controls.
Mean retinal and foveal sensitivity were comparable between the CVD group and the control group.

Conclusions:

Congenital red-green CVD does not present discernible anatomical abnormalities in major retinal layers via SD-OCT.
A narrower foveal pit is the only structural difference observed in CVD patients.
Further research with larger cohorts is recommended to confirm these findings and explore potential subtle structural variations.