Conventional brain implants are typically rigid and use materials that can irritate fragile tissue. Such devices have limited in-vivo lifetime and prevent more complicated functionality to be built into them. They typically do one task, such as drug delivery or neural sensing, and usually can’t deliver therapy while monitoring its effects in real time. Scientists at MIT have now developed a novel type of fibers that can simultaneously transmit electrical and optical stimulation, deliver drugs, and read the brain’s electric signals while causing little irritation to nearby tissue.
The polymer fibers in some ways mimic our own nerves but have electrodes, a tube, and an optical channel built. These are created by first making them relatively large and easy to work with. Once the components are built, positioned, and aligned, the device is heated to soften it up. Carefully sucking it through a narrow straw while still hot squishes it together into a very narrow fiber that maintains the functional components created earlier. Repeating this process makes the implant progressively narrower.
The new implants should help further develop the science of optogenetics, which uses light to stimulate small groups of brain neurons, as well as advance research into all kinds of brain therapies in which multi-modal stimulation and simultaneous monitoring can have a great benefit.
Study in Nature Biotechnology: Multifunctional fibers for simultaneous optical, electrical and chemical interrogation of neural circuits in vivo…