@article {Pisanello094524, author = {Ferruccio Pisanello and Gil Mandelbaum and Marco Pisanello and Ian A. Oldenburg and Leonardo Sileo and Jeffrey E. Markowitz and Ralph E. Peterson and Andrea Della Patria and Trevor M. Haynes and Mohamed S. Emara and Barbara Spagnolo and Sandeep R. Datta and Bernardo L. Sabatini and Massimo De Vittorio}, title = {Dynamically controlled light delivery over large brain volumes through tapered optical fibers}, elocation-id = {094524}, year = {2016}, doi = {10.1101/094524}, publisher = {Cold Spring Harbor Laboratory}, abstract = {Optogenetics promises spatiotemporal precise control of neural processes using light. However, the spatial extent of illumination within the brain is difficult to control and cannot be adjusted using standard fiber optics. We demonstrate that optical fibers with tapered tips can be used to illuminate either large brain volumes or dynamically selectable subregions. Remotely adjusting the light input angle to the fiber varies the light-emitting portion of the taper over several millimeters without movement of the implant. We use this mode to activate dorsal versus ventral striatum of individual mice and reveal different effects of each manipulation on motor behavior. Conversely injecting light over the full numerical aperture of the fiber results in light emission from the entire taper surface, achieving broader and more efficient optogenetic activation of neurons when compared to the standard flat-faced fiber stimulation. Thus, tapered fibers permit focal or broad illumination that can be precisely and dynamically matched to experimental needs.}, URL = {https://www.biorxiv.org/content/early/2016/12/15/094524}, eprint = {https://www.biorxiv.org/content/early/2016/12/15/094524.full.pdf}, journal = {bioRxiv} }