Selective stimulation with a chronic slowly penetrating interfascicular nerve electrode

The acute functional selectivity of the Slowly Penetrating Interfascicular Nerve Electrode (SPINE) has been demonstrated previously. The authors present a chronic SPINE design and results of chronic studies of functional selectivity and safety. Five cats were implanted up to 5 months without chronic physiologic deficit. One cat showing physiologic loss following surgery recovered within 3 weeks. Stimulation results show the chronic SPINE electrode selectively generates function in all directions of moment space. Stimulation results also show functional differences between pulse width and pulse amplitude modulation recruitment, suggesting advantages to simultaneous modulation of both pulse width and pulse amplitude.