May 14, 2024

Humans vs. Monkeys – Do We See Colors the Same Way?

The blue pedicle, a short wavelength delicate nerve cell, offers rise to complex circuitry that starts a neural code for color understanding. It is the part of the retina responsible for the sharp visual skill required to see essential details, such as words on a page or whats ahead while driving, and for color vision.
Other functions the researchers found in the nerve cell connections in human color vision were not anticipated, based on earlier nonhuman primate color vision designs.
The ability to find ripe fruit among the moving light of a forest, for example, might have provided a selective advantage for particular color visual circuity. The real results of environment and habits on color vision circuitry have not yet been established.

Bulb-like axon terminals of cone photoreceptors in the marmosets foveal retina. The blue pedicle, a short wavelength sensitive neuron, generates intricate circuitry that begins a neural code for color perception. Credit: Yeon Jin Kim/University of Washington Biological Structure
Research study shows that certain neural cell circuits accountable for color vision are exclusive to humans.
Research study in the field of color vision has actually discovered new proof recommending that humans have the capability to identify a wider spectrum of blue hues compared to monkeys.
According to researchers, “unique connections found in the human retina might show current evolutionary adaptations for sending boosted color vision signals from the eye to the brain.” Their findings were just recently published in the journal Proceedings of the National Academy of Sciences.
Yeon Jin Kim, acting instructor, and Dennis M. Dacey, teacher, both in the Department of Biological Structure at the University of Washington School of Medicine in Seattle, led the worldwide, collective project.

They were joined by Orin S. Packer of the Dacey laboratory; Andreas Pollreisz at the Medical University of Vienna, Austria; as well as Paul R. Martin, professor of experimental ophthalmology, and Ulrike Grünert, associate professor of ophthalmology and visual science, both at the University of Sydney, Australia, and the Save Sight Institute.
The researchers compared connections in between color-transmitting afferent neuron in the retinas of human beings with those in two monkeys, the Old World macaque and the New World typical marmoset. The ancestors of modern-day people diverged from these 2 other primate types roughly 25 million years back.
By utilizing a fine-scale tiny reconstruction method, the scientists wished to identify if the neural circuitry of the areas connected with color vision is saved across these 3 species, despite each taking their own independent evolutionary paths.
The scientists took a look at the lightwave-detecting cone cells of the fovea of the retina. This little dimple is largely packed with cone cells. It is the part of the retina responsible for the sharp visual acuity needed to see crucial information, such as words on a page or whats ahead while driving, and for color vision.
Cone cells come in three level of sensitivities: short, medium, and long wavelengths. Information about color comes from neural circuits that process info throughout various cone types.
The researchers discovered that a certain short-wave or blue-sensitive cone circuit discovered in human beings is absent in marmosets. It is also different from the circuit seen in the macaque monkey. Other functions the researchers discovered in the afferent neuron connections in human color vision were not anticipated, based on earlier nonhuman primate color vision designs.
A better understanding of the species-specific, complicated neural circuitry that codes for color understanding could eventually assist describe the origins of the color vision qualities that stand out to human beings.
The ability to identify ripe fruit among the moving light of a forest, for example, may have offered a selective benefit for specific color visual circuity. The real effects of environment and behavior on color vision circuitry have actually not yet been developed.
More generally, relative research studies of neural circuits at the level of connections and signaling in between afferent neuron, the researchers kept in mind, might help respond to many other questions. These include elucidating the underlying logic of neural circuit design and offering insight into how advancement has modified the nerve system to help shape understanding and behavior.
Referral: “Comparative connectomics exposes noncanonical circuitry for color vision in human foveal retina” by Yeon Jin Kim, Orin Packer, Andreas Pollreisz, Paul R. Martin, Ulrike Grünert and Dennis M. Dacey, 25 April 2023, Proceedings of the National Academy of Sciences.DOI: 10.1073/ pnas.2300545120.
The research study was funded by the National Institutes of Health and the National Eye Institute.