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 Plant Responses to Light

Photoreceptors and Plant Responses to Light

Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.

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...

The Pineal Gland

The Pineal Gland

The pineal gland, a diminutive endocrine structure named for its pinecone-shaped appearance, is situated atop the third ventricle within the diencephalon region of the forebrain. This gland, composed of secretory cells known as pinealocytes arranged in compact cords and clusters around dense particles of calcium salts, plays a pivotal role in hormonal regulation.
The primary secretion of the pineal gland is the hormone melatonin, derived from serotonin. The concentration of melatonin in the...

Management of Insomnia

Management of Insomnia

The sleep cycle, an integral part of human health, consists of several stages with distinct characteristics and functions. It begins with a transition from wakefulness to sleep, known as the light sleep phase, followed by the restorative deep sleep phase, essential for physical recovery and growth. The cycle concludes with the Rapid Eye Movement (REM) phase, characterized by high brain activity and vivid dreaming. Insomnia, a prevalent sleep disorder, involves difficulty falling asleep, staying...

You might also read

Related Articles

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

Sort by

Same author

Does the iPad Night Shift mode reduce melatonin suppression?

Lighting research & technology (London, England : 2001)·2019

Same author

Effect of exposure duration and light spectra on nighttime melatonin suppression in adolescents and adults.

Lighting research & technology (London, England : 2001)·2019

Same author

Non-visual effects of light: how to use light to promote circadian entrainment and elicit alertness.

Lighting research & technology (London, England : 2001)·2018

Same author

Toward the Development of Standards for Yellow Flashing Lights Used in Work Zones.

Lighting research & technology (London, England : 2001)·2018

Same author

Research Note: A self-luminous light table for persons with Alzheimer's disease.

Lighting research & technology (London, England : 2001)·2016

Same author

Comparisons of three practical field devices used to measure personal light exposures and activity levels.

Lighting research & technology (London, England : 2001)·2014

Search research articles

Related Experiment Video

Updated: Jul 24, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model

Published on: September 7, 2013

Human melatonin suppression by light: a case for scotopic efficiency.

M S Rea¹, J D Bullough, M G Figueiro

¹Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA. ream@rpi.edu

Neuroscience Letters

|February 13, 2001

Summary

Human nighttime light exposure significantly suppresses melatonin. This study found that rod-based vision, not cone-based vision, is key for regulating melatonin levels, suggesting rods play a crucial role.

More Related Videos

Blue-hazard-free Candlelight OLED

Blue-hazard-free Candlelight OLED

Published on: March 19, 2017

Investigating Migraine-Like Behavior Using Light Aversion in Mice

Investigating Migraine-Like Behavior Using Light Aversion in Mice

Published on: August 11, 2021

Related Experiment Videos

Last Updated: Jul 24, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model

Published on: September 7, 2013

Blue-hazard-free Candlelight OLED

Blue-hazard-free Candlelight OLED

Published on: March 19, 2017

Investigating Migraine-Like Behavior Using Light Aversion in Mice

Investigating Migraine-Like Behavior Using Light Aversion in Mice

Published on: August 11, 2021

Area of Science:

Ophthalmology
Endocrinology
Chronobiology

Background:

Melatonin, a hormone regulating sleep-wake cycles, is suppressed by light exposure.
The specific photoreceptor system mediating light-induced melatonin suppression in humans is not fully understood.

Purpose of the Study:

To investigate the relationship between different light conditions and acute melatonin suppression in human males.
To determine whether cone-based (photopic) or rod-based (scotopic) illuminance better predicts melatonin suppression.

Main Methods:

Human adult males participated in four nighttime laboratory sessions.
Participants were exposed to controlled combinations of two illuminances and two spectral power distributions.
Melatonin levels were measured to assess acute suppression in response to light stimuli.

Main Results:

A dose-dependent suppression of melatonin was observed in response to light.
Photopic illuminance was insufficient to accurately predict the degree of melatonin suppression.
Scotopic illuminance showed a strong, nearly monotonic correlation with melatonin suppression, implicating rod function.

Conclusions:

Rod-based visual mechanisms, or a rod-dominated system, appear critical for regulating human melatonin suppression.
While rods are implicated, novel photoreceptors cannot be excluded as potential mediators of this response.