This project proposes the development of flexible multiple contact nerve cuff electrodes with an embedded integrated circuit (IC) electrically connected via a novel high density interconnect and advanced biocompatible packaging scheme. The proposed microfabricated polyimide/silicone hybrid cuff electrode arrays will provide capabilities for both selective stimulation and recording from compound peripheral nerves. The innovative fabrication process advances what is currently a labor-intensive manual process to batch microfabrication, and thereby allows an increase in the density and precision of electrode contacts. The innovative hybrid structure results in a highly flexible electrode, and the novel on-board IC and interconnects reduce the required number of lead wires, which are associated with failure and neural injury. We will demonstrate the utility of the device for closed-loop control of bladder function - including continence and emptying. In addition to extensive in vitro testing of prototype devices, active devices will be implanted into an animal model (i.e. cat) for acute and chronic in vivo testing of functionality, biocompatibility, and dielectric integrity of the packaging scheme. This work will be completed in collaboration with Prof. Warren Grill of Duke University. This technology is also applicable to neural prostheses in other areas of the peripheral nervous system, including peripheral motor nerve stimulation for re-animation of paralyzed limbs, hypoglossal nerve stimulation to treat obstructive sleep apnea, and vagus nerve stimulation for treatment of epilepsy, depression, and heart failure.
The integrated neural interface system proposed in this project will enable inclusion of a tightly coupled IC as part of a biocompatible, implantable flexible device, providing high bandwidth information exchange between neural interfaces and the IC. This capability is a vital requirement for fully-implantable, closed-loop biological- machine interface systems to restore motor and sensory function to people afflicted with irreversible nerve damage from injury, stroke, or neurodegenerative diseases. The technology being developed is directly applicable to a broad range of neural interface devices including advanced prosthetic limbs, visual prostheses, and systems for the treatment of obstructive sleep apnea, epilepsy, depression, and heart failure.