Translator Disclaimer
11 March 2008 Laser stimulation of the auditory system at 1.94 μm and microsecond pulse durations
Author Affiliations +
Light can artificially stimulate nerve activity in vivo. A significant advantage of optical neural stimulation is the potential for higher spatial selectivity when compared with electrical stimulation. An increased spatial selectivity of stimulation could improve significantly the function of neuroprosthetics, such as cochlear implants. Cochlear implants restore a sense of hearing and communication to deaf individuals by directly electrically stimulating the remaining neural cells in the cochlea. However, performance is limited by overlapping electric fields from neighboring electrodes. Here, we report on experiments with a new laser, offering a previously unavailable wavelength, 1.94μm, and pulse durations down to 5μs, to stimulate cochlear neurons. Compound action potentials (CAP) were evoked from the gerbil cochlea with pulse durations as short as 1μs. Data show that water absorption of light is a significant factor in optical stimulation, as evidenced by the required distance between the optical fiber and the neurons during stimulation. CAP threshold measurements indicate that there is an optimal range of pulse durations over which to deposit the laser energy, less than ~100μs. The implications of these data could direct further research and design of an optical cochlear implant.
© (2008) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Agnella D. Izzo, Joseph T. Walsh Jr., Heather Ralph, Jim Webb, Jonathon Wells, Mark Bendett, and Claus-Peter Richter "Laser stimulation of the auditory system at 1.94 μm and microsecond pulse durations", Proc. SPIE 6854, Optical Interactions with Tissue and Cells XIX, 68540C (11 March 2008);


Back to Top