Correction to: Nature Neuroscience https://doi.org/10.1038/s41593-018-0314-y, published online 21 January 2018.
In the version of this article initially published, errors occurred in Fig. 5: in panel a, the leftmost label on the x axis should have read “COMP→2AFC” and the rightmost x axis marks in Fig. 5c should have been labeled “1.12”. The errors have been corrected in the HTML and PDF versions of the article.