Disparity-selective cells in visual cortical neurons have preferred disparities of only a few degrees whereas disparity in natural environments ranges over tens of degrees.
The possible explanation offered by Zhao et al. assumes that animals actively keep disparity within a small range, during development, and therefore only selectivity for small disparity develops.⇒
Zhao et al. present a model of joint development of disparity selectivity and vergence control.⇒
Zhao et al.'s model develops both disparity selection and vergence control in an effort to minimize reconstruction error.
It uses a form of sparse-coding to learn to approximate its input and a variation of the actor-critic learning algorithm called natural actor critic reinforcement learning algorithm (NACREL).
The teaching signal to the NACREL algorithm is the reconstruction error of the model after the action produced by it.⇒