Baby-brains have built-in baseline for color categorization

Beauty may be in the eye of the beholder, but what about color? Color occupies a weird space in our visual perception, being both objectively measurable as a specific frequency of light, but also subject to personal and cultural influences. An oft-cited example is that a group of people might all be observing the same 490 nm  light, it might be perceived as a more distinct color to a Russian speaker thanks to the specific vocabulary that language has for blue versus light blue. To try to hone in on the line between nature and nurture on this issue, scientists have started looking at pre-verbal babies to see what they thought of color before pesky things like words muddle their perception too much.

Since communicating with babies that can’t talk isn’t very easy, researchers opted to just monitor brain activity directly. They were most interested in the occipitotemporal region of the brain, where a lot of visual processing is handled. The babies were then shown colors that would shift, either to a second color entirely, or to a different shade of the same color. If all colors were being treated as equally different light frequencies, the babies’ brains would respond to new colors with as much as they responded to new shades of the same color. The bigger distinctions adults make between red and blue would then have to be a learned concept from language or cultural emphasis.

Appreciating blue, green or white without words

The babies’ visual processing ended up indicating the opposite scenario. They responded more to shifts from red to blue than from light blue to dark blue. Activity took place in both hemispheres of the brain, rather than being focused on the language-heavy regions in the left hemisphere alone. This activity also matched the patterns seen in adult brains as well, further supporting the notion that these distinctions are wired into our perception rather than invented through culture and language. Researchers are now going to look at when in a child’s development the language influences do start to shape perception, helping us understand just how much culture can change this perceptual baseline.

Source: NEUROSCIENCE Babies’ Innate Sense of Color by Jordana Cepelewicz, Scientific American: Mind