Laser Stimulation Control System Design of the Auditory Nerve

Abstract:

Optical stimulation of the inner ear, the cochlea, has been proved as a possible alternative to conventional cochlear implant with the hypothetical improvement of dynamic range and frequency resolution. Moreover, the laser has good directionality character and optical signal between adjacent fibers do not readily interfere. Therefore, cochlear implant based on optical stimulation is promising for further exploration and development. The design of an experimental system for optical stimulation of the cochlea is introduced in this paper. For the important part, the selection of NIR laser and the optical signal control methods were discussed. The pulsed laser light was coupled by fiber or fiber array and radiated to the cochlea. For each channel laser pulse, the width modulation was varied from 10us to 1ms, the pulse repetition rate from 5 Hz to 10 KHz, single pulse energy from 0 to 3.6mJ. The application of high precision DAC made the resolution of the pulse energy regulation up to 1uJ/div. The experiment results show that this design and implementation can meet the requirements on further optical stimulation of the cochlea research.

• Periodical: Advanced Materials Research (Volume 1046)
• Pages: 116-120
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1046.116
• Online since: October 2014
• Authors: Nan Yang, Jing Xuan Wang, Lan Tian*, Yong Wang
• Keywords: Cochlear Implant, D/A Conversion, FPGA, Laser Pulse Modulation

References

[1] von Ilberg C，Kiefer J et al. Electric-acoustic stimulation of the auditory system - New technology for severe hearing loss. ORL-JOURNAL FOR OTO-RHINO-LARYNGOLOGY AND ITS RELATED SPECIALTIES, 1999, 61: 334-340.

DOI: 10.1159/000027695

[2] Friesen LM, Shannon RV et al. Speech recognition in noise as a function of the number of spectral channels: Comparison of acoustic hearing and cochlear implants. JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, 2001, 110: 1150-1163.

DOI: 10.1121/1.1381538

[3] Leal MC, Shin YJ et al. Music perception in adult cochlear implant recipients. ACTA OTO-LARYNGOLOGICA, 2003, 123: 826-835.

DOI: 10.1080/00016480310000386

[4] Mens LH, Oostendrop T, van den Broek P. Cochlear implant generated surface potentials: current spread and side effects. Ear Hear , 1994，15(4): 339-345.

DOI: 10.1097/00003446-199408000-00008

[5] Teudt IU, Maier H, Richter CP et al. Acoustic Events and Optophonic, Cochlear Responses Induced by Pulsed Near-Infrared LASER. IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING 2011, 58: 1648-1655.

DOI: 10.1109/tbme.2011.2108297

[6] Littlefield P, Izzo AD et al. Characterization of single auditory nerve fibers in response to loser stimulation. OPTICAL INTERACTIONS WITH TISSUE AND CELLS XIX, (2008).

[7] Rajguru SM, Matic AI et al. Optical cochlear implants: Evaluation of surgical approach and laser parameters in cats. HEARING RESEARCH . 2010, 269: 102-111.

DOI: 10.1016/j.heares.2010.06.021