Implantable microtechnologies for the brain: Challenges and strategies for reliable operation

Implantable microtechnologies and microelectrodes are crucial for the success for the next generation of prosthetic devices for the brain. This paper reviews some of the challenges in developing reliable technologies that will interface with neurons in the brain. We also recount here some of the milestones in our own successful effort to create interfaces with neurons in the brain. We have used a novel approach of developing neural interfaces using MEMS technologies that can be moved within the brain after implantation. The strategy is to enhance reliability by either creating stable neuron-electrode interfaces or by seeking new neuron electrode interfaces in the event of failure or deterioration of function in the interface. We have developed novel microactuators, microelectrodes, packaging and interconnect technologies to achieve the above goals. The success of this technology in recording good quality neuronal signals in chronic experiments, analysis of failure modes, the packaging efforts and reliability analysis to improve the longevity of the implant is addressed below.