New Research Explains Universal Perception of Four Primary Colors
Researchers at UC Berkeley, including postdoctoral fellow Alexander Belsten and neuroscientist Bruno Olshausen, have developed a new theory explaining why humans universally perceive and categorize colors based on four 'pure' hues: red, yellow, green, and blue. This phenomenon has long puzzled biologists and linguists, as the human eye has three types of cone cells that detect different wavelengths of light, not four. The theory suggests that the brain, for simplicity, represents the restricted palette of colors found in the natural world as combinations of these four pure colors. This allows for a parsimonious representation of any hue as a combination of two of the four, and also enables mutually exclusive color pairs, such as red versus green and blue versus yellow. The study utilized recently developed datasets of the color or spectral distribution of natural scenes to simulate how the human eye's cones respond to natural images, revealing that the distribution of colors in nature is highly asymmetric ... 
