What is Olo and How is Olo a New Color?

What is Olo?

Olo is a newly perceived color described as an intensely saturated blue-green or teal-like hue, discovered through experiments conducted by researchers at the University of California, Berkeley, and the University of Washington. The color was reported in a study published on April 18, 2025, in Science Advances. Unlike colors in the natural world, Olo cannot be seen with the naked eye under normal conditions—it requires a specialized technique called the "Oz Vision System," which uses laser pulses to selectively stimulate specific cells in the retina.

New Color – Olo

The name "Olo" comes from the binary code 010, representing the selective activation of only the medium-wavelength (M) cone cells in the retina, while leaving the long-wavelength (L) and short-wavelength (S) cones unstimulated. This is significant because, in natural vision, light always stimulates a combination of L, M, and S cones due to their overlapping sensitivities, limiting the range of colors we can perceive. By isolating M-cone stimulation, researchers created a color perception that lies outside the normal human "color gamut" (the range of colors we can naturally see).

How is Olo a New Color?

Olo is considered "new" because it represents a perceptual experience that cannot be achieved with natural light or conventional displays. Here’s why:

1. Unique Stimulation of M Cones:

   • Human color vision relies on three types of cone cells in the retina: L cones (sensitive to red/long wavelengths), M cones (green/medium wavelengths), and S cones (blue/short wavelengths). In nature, any light stimulates at least two cone types due to their overlapping sensitivities. For example, green light primarily activates M cones but also affects L and S cones to some extent.

     
     

   • The Oz Vision System uses precise lasers and eye-tracking to stimulate only M cones in a small patch of the retina (about 1,000 cells), creating a signal that the brain interprets as a color never encountered in natural conditions. This results in a blue-green hue with "unprecedented saturation," described as more vivid than even the most saturated natural colors, like those from a green laser pointer.

     
     

1. 
   
   • 
     

2. Beyond the Natural Color Gamut:

   • The human color gamut is defined by the combinations of L, M, and S cone activations possible with natural light. Olo lies outside this gamut because it’s produced by an artificial, pure M-cone signal. In experiments, participants couldn’t match Olo to any conventional color without adding white light to desaturate it, confirming it’s perceptually distinct.

     
     

   • Participants described Olo as a "jaw-dropping" blue-green, more intense than teal or peacock green. The closest displayable approximation is a teal shade (hex code #00ffcc), but researchers emphasize that this pales in comparison to the actual experience.

     
     

3. Novel Perceptual Experience:

   • Color is a subjective experience created by the brain’s interpretation of cone signals. Olo is new in the sense that it’s a sensation the brain doesn’t encounter in everyday life. As Professor Ren Ng, a study co-author, explained, it’s like seeing a color as vivid as "the most intense baby pink you’ve ever seen" and being told it’s a new color called red. The brain perceives Olo as distinct due to the unique M-cone-only signal.

     
     

Is Olo Truly a New Color? Skepticism and Debate

Some experts question whether Olo is genuinely a "new" color or simply an exaggerated version of an existing hue. Here’s the debate:

• Supporting Evidence:

  • Color-Matching Tests: In experiments, participants compared Olo to adjustable hues and consistently needed to add white light to match it to the closest monochromatic color (a teal-like shade). This suggests Olo’s saturation exceeds anything in the natural color space.

    
    

  • Perceptual Uniqueness: All five participants (four men, one woman, including researchers) described Olo similarly as a hyper-saturated blue-green, distinct from any known color. The consistency of their reports supports the claim of a novel perception.

    
    

  • Technological Breakthrough: The ability to isolate M-cone stimulation is unprecedented, as natural light cannot achieve this. This artificial signal creates a brain response that’s theoretically impossible in everyday vision, making Olo a new perceptual phenomenon.

    
    

• Skeptical Views:

  • Not a New Hue: Vision scientist John Barbur from City St George’s, University of London, argues that Olo isn’t a new color but a highly saturated green produced by M-cone stimulation. Since its hue is still within the blue-green range, it may not be a fundamentally new color, just an extreme version of an existing one.

    
    

  • Subjectivity of Color: Color is a brain construct, not a physical property. Critics note that calling Olo "new" depends on subjective interpretation, and its hue (blue-green) isn’t outside the known spectrum—it’s the saturation that’s unique.

    
    

  • Limited Practicality: Barbur and others suggest the discovery has "limited value" since Olo can only be seen in a lab with complex equipment, and its perceptual difference may not justify calling it a new color.

• Counter to Skepticism:

  • The Berkeley team argues that Olo’s novelty lies in its experiential uniqueness, not just its hue. Since no natural or artificial light source can replicate the pure M-cone signal, the brain’s response is a new phenomenon, even if the hue resembles blue-green.

    
    

  • The study’s color-matching results provide empirical evidence that Olo lies outside the normal gamut, as participants couldn’t replicate it without altering saturation. This supports the claim of a distinct perceptual experience.

    
    

How Do You Know If It’s Truly a New Color You’ve Never Seen?

Unfortunately, you can’t experience Olo yourself without participating twisted in a similar experiment, as it requires the Oz Vision System, which is currently limited to a lab setting. Here’s how you can evaluate whether Olo is a color you’ve never seen:

• You Can’t See It on Screens or in Nature:

  • Olo cannot be displayed on monitors, smartphones, or TVs because these devices use RGB (red, green, blue) technology, which mimics natural light and always stimulates multiple cone types. Any image claiming to show Olo (e.g., a turquoise square with hex #00ffcc) is only an approximation. If you’ve seen teal or peacock blue, you’ve seen the closest possible match, but Olo’s saturation is reportedly far more intense.

    
    

  • If you encounter Olo in a lab setting with the Oz system, you’d know it’s new because it would feel perceptually distinct—like a blue-green so vivid it surpasses any laser pointer or natural color you’ve seen. Participants described it as “jaw-dropping” and “unprecedented.”

    
    

• Perceptual Test:

  • If you were a participant, researchers would test your perception by asking you to match Olo to other colors using a dial. If you consistently need to desaturate Olo with white light to match it to a teal-like shade, it confirms Olo’s unique saturation, indicating it’s outside your normal color experience.

    
    

  • The “wow” factor reported by participants suggests you’d feel a sense of novelty, like seeing a color that doesn’t fit your mental map of hues.

    
    

• Trust the Science (with Caution):

  • The study’s methodology, published in a peer-reviewed journal, provides credibility. The researchers mapped participants’ retinas to target M cones precisely, and their consistent reports of a hyper-saturated blue-green support the claim.

    
    

  • However, independent replication is needed to confirm the findings, as one X user noted: “Per the scientific method, this experiment must be conducted by other scientists to determine if the theory these researchers put forth is verifiable.” Until replicated, Olo’s status as a “new” color remains theoretically compelling but not fully proven.

    
    

• Consider Your Own Vision:

  • If you have normal color vision, your cone cells work like those of the participants, so Olo would theoretically be as new to you as it was to them. If you’re colorblind (e.g., red-green colorblindness), your ability to perceive Olo might differ, as some forms of colorblindness affect M or L cone function. The study only included participants with normal vision.

Why Does This Matter?

The discovery of Olo is significant for several reasons:

• Vision Research: It proves that human color perception can be expanded beyond natural limits, opening avenues to study how the brain processes novel visual signals. This could lead to insights into color blindness, visual disorders, or even neural plasticity.

  
  

• Potential Applications: While Olo can’t be shown on screens now, the Oz technique might inspire future technologies, like advanced virtual reality or visual prosthetics, to simulate new colors or enhance vision for those with deficiencies.

  
  

• Philosophical Implications: Olo challenges our understanding of perception, suggesting there are sensory experiences beyond what we encounter in everyday life. It raises questions about the nature of color as a subjective, brain-generated phenomenon.