A coaxial optrode as multifunction write-read probe for optogenetic studies in non-human primates.

•Developed powerful new device tool for optogenetic studies in non-human primates.•Multifunction “coaxial optrode” was deployed in non-human primates, rats, and mice.•Device achieved targeted optical stimulation safely with minimal cortical damage.•Device design and performance correlated well with computational models.•Device was able to quantify and map local opsin expression in the brain.