What is it about?

Comparative connectomics – the study of neural circuits at synaptic resolution across species or the life span – promises to reveal how evolution modifies the nervous system to shape behavior and perception. Here we compare the synaptic connectome for a color-coding circuit in the human retina with the comparable circuits in both marmoset and macaque monkey.

Featured Image

Why is it important?

We discover a circuit in human that is absent in the marmoset and show further that for the human retina synaptic motifs do not follow the canonical architecture established in macaque monkey. Our results may help to explain why some aspects of human color perception are not well predicted from physiological studies of macaque monkey visual system.


Some nerve cells circuits for colour vision are uniquely human, shows a new study led by Yeon Jin Kim and Dennis Dacey from the University of Seattle Washington, and including Save Sight researchers Ulrike Grünert and Paul Martin. Using a fine-scale electron microscopic reconstruction method, they compared the connections of colour-coding receptor cells in the retinas of humans with two species of non human primates (macaque and marmoset monkeys). They discovered that a short-wave sensitive (“blue”) cone circuit in humans is absent in marmosets, and is also different to the circuit seen in macaque monkey. The distinct connections of human retina may indicate recent evolutionary adaptations for sending enhanced colour vision signals from the eye to the brain. The study was published this week in the Proceedings of the National Academy of Sciences of the USA.

Yeon Jin Kim
University of Washington

Read the Original

This page is a summary of: Comparative connectomics reveals noncanonical wiring for color vision in human foveal retina, Proceedings of the National Academy of Sciences, April 2023, Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.2300545120.
You can read the full text:




The following have contributed to this page