Three-dimensional multiwaveguide probe array for light delivery to distributed brain circuits

To deliver light to the brain for neuroscientific and neuroengineering applications like optogenetics, in which light is used to activate or silence neurons expressing specific photosensitive proteins, optical fibers are commonly used. However, an optical fiber is limited to delivering light to a single target within the three-dimensional structure of the brain. We here describe the design and fabrication of an array of thin microwaveguides which terminate at a 3-dimensionally distributed set of points, appropriate for delivering light to targets distributed in a 3-dimensional pattern throughout the brain.