Retinotopy Inspired Brain Encoding Model and the All-for-One Training
  Recipe
Huzheng Yang Jianbo Shi James Gee
Brain encoding models aim to predict brain voxel-wise responses to stimuli
images, replicating brain signals captured by neuroimaging techniques. There is
a large volume of publicly available data, but training a comprehensive brain
encoding model is challenging. The main difficulties stem from a) diversity
within individual brain, with functional heterogeneous brain regions; b)
diversity of brains from different subjects, due to genetic and developmental
differences; c) diversity of imaging modalities and processing pipelines. We
use this diversity to our advantage by introducing the All-for-One training
recipe, which divides the challenging one-big-model problem into multiple small
models, with the small models aggregating the knowledge while preserving the
distinction between the different functional regions. Agnostic of the training
recipe, we use biological knowledge of the brain, specifically retinotopy, to
introduce inductive bias to learn a 3D brain-to-image mapping that ensures a)
each neuron knows which image regions and semantic levels to gather
information, and b) no neurons are left behind in the model.
  We pre-trained a brain encoding model using over one million data points from
five public datasets spanning three imaging modalities. To the best of our
knowledge, this is the most comprehensive brain encoding model to the date. We
demonstrate the effectiveness of the pre-trained model as a drop-in replacement
for commonly used vision backbone models. Furthermore, we demonstrate the
application of the model to brain decoding. Code and the model checkpoint will
be made available.