Figure 8. Motion training induces decrease in noise correlations and increase in direction selectivity.

(a) Experimental timeline. Shortly after eye opening animals received 4–6 hours of motion training. (b) Example of (black point in d) direction selectivity increase following motion training. (c) Example of decrease in pairwise noise correlations following motion training. (d) Following motion training, noise correlations decrease and direction selectivity increases, while direction selectivity did not change and noise correlations increased following flash training. In control (no training) animals, noise correlations and direction selectivity remained unchanged. (e) Change in noise correlation as a function of training type, pooled across all animals. (f) Before training, noise correlation is highest in pairs for which the difference in preferred direction and cortical distance is small (map generated as in Fig. 4d–f using a Gaussian smoothing kernel, σ_x=15 micron, σ_y=15 deg). (g) The correlation in this group is reduced after training, primarily due to the subset of pairs maintaining a small difference in preferred direction, as opposed to those preferring opposite directions after training. (h–k): Discriminability measures in training data set. (h) Discriminability of the trained orientation increases with training. Switching the pre- and post-training variances (light green) does not change discriminability. (i) In larger groups of cells, the change in variance, but not noise correlation, had a detectable effect on discriminability. (j) Effect of eliminating noise correlations by trial shuffling on discriminability in training dataset. (k) Difference between solid and dashed lines from j. Shaded regions show ±1 SEM.