Large-scale color biases in the retinotopic functional architecture are shared across human brains

Abstract

AbstractAlthough the neural processing of chromatic and spatial features is intertwined, it is unknown how consistent this spatio-chromatic coding is across different brains. In this fMRI study we predicted the color a person was seeing using a classifier that has never been trained on chromatic responses from that same brain, solely by taking into account: (1) chromatic responses in other individuals’ brains and (2) commonalities between spatial coding in brains used for training and the test brain. Fitting shared response models to fMRI responses elicited by spatially defined and achromatic retinotopic mapping stimuli, we transformed subject-specific color responses to a common functional space. In this space we successfully decoded color across observers based on activity patterns in V1-V3, hV4 and LO1. Examining classification weights, we found that systematic large-scale retinotopic biases for the different colors may explain at least partially the observed agreement of neural color coding between brains.