Received: 15 June 2016
Accepted: 21 November 2016
First Online: 9 January 2017
Change Date: 11 January 2017
Change Type: Erratum
Change Details: In the version of this article initially published online, the annotation above the ChR2 bars in Figure 6k appeared as NNN instead of ***. Also, the third author's name was given as Zina Perova; the correct name is Zinaida Perova. The errors have been corrected in the print, PDF and HTML versions of this article.
: The authors declare no competing financial interests.
Free to read: This content has been made available to all.