Neuroscience suggests that yes, when you see purple, it's the same purple I see

A team led by a Canadian neurobiologist has used brain imaging technology to map how colours are processed in the brain, answering age old questions about colour perception.  We do, it seems, see colours similarly, as near as their technique can determine

Bevil Conway, chief of the U.S. National Eye Institute's sensation, cognition and action unit used magnetic encephalography to monitor the neurological activity in volunteers as they observed images of different colours.

He and his team then used a machine learning system to interpret the patterns of brain activity they recorded. The algorithm was then able to accurately predict from the brain activity patterns what colour the test subjects were observing.

Effectively that meant the researchers were able to read the minds of the volunteers, at least for the colour they were observing.

Brain activation patterns were not identical between participants, likely because of small variation in head and brain shape. They were, however, quite similar in that participants had similarly distinctive patterns of activation for both subtle and large differences in colour. 

One interesting finding was that patterns of brain activation were rich in all participants for shades and intensities of "warm" colours like red, orange and yellow.  For "cooler" colours like blue and green, participants shared weaker brain activation patterns. Essentially their brains devoted more energy and processing power to warmer colours than to cooler colours.

These similarities, according to Conway, suggest that human perceptions of colours are all quite similar, and likely due to evolutionary pressures.

The team's research study was published in the journal Current Biology.

Hear Bevil Conway's interview with Bob McDonald by clicking on the listen icon above.

Produced by Sonya Buyting.  Written by Jim Lebans