Analysis of receptive fields.

<p>(A) Examples of receptive fields learned by the 81- and 36-hidden unit models after training on different training sets (rows). Each receptive field is shown on a 28 x 28 step grid. Heat maps show areas with high weight values, which represent highly sensitive zones. Samples were chosen to show a variety of receptive field morphologies. The number on the bottom left corner of each receptive field is the number of peaks returned by our peak counting algorithm, which measures receptive field complexity. (B) The average complexity of each network under different architectures and training sets. Each data point is the mean peak count of receptive fields from that model on one iteration, with grey violin plots showing the overall frequency distribution across the 20 iterations we performed for each architecture and training set.