TY - JOUR
T1 - Infrared neural stimulation at different wavelengths and pulse shapes
AU - Xu, Yingyue
AU - Magnuson, Mario
AU - Agarwal, Aditi
AU - Tan, Xiaodong
AU - Richter, Claus Peter
N1 - Funding Information:
This work was supported by the NIH , R01-DC011855, R56DC017492 and by the Hugh Knowles Center for Clinical and Basic Science in Hearing and its Disorders at Northwestern University .
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/7
Y1 - 2021/7
N2 - Neural stimulation with infrared radiation has been explored for brain tissue, peripheral nerves, and cranial nerves including the auditory nerve. Initial experiments were conducted at wavelengths between λ = 1850 and λ = 2140 nm and the radiant energy was delivered with square pulses. Water absorption of the infrared radiation at λ = 1860 nm is similar to absorption at wavelengths between λ = 1310 and λ = 1600 nm, which are in the radiation wavelength range used for the communication industry. Technology for those wavelengths has already been developed and miniaturized and is readily available. The possibility of the infrared light to evoke compound action potentials (CAP) in the cochlea at λ = 1,375, λ = 1,460, and λ = 1550 nm was explored and compared to that of λ = 1860 nm in guinea pigs. Furthermore, rise and fall times of the 100 μs long pulses were changed and four basic pulse shapes (square, triangular, ramp-up, and ramp-down) were explored in their ability to evoke a CAP. In animals with pure tone threshold averages (PTAs) above 70 dB SPL, the results show that the favorable wavelength is λ = 1460 nm to reach threshold for stimulation and λ = 1375 nm or λ = 1460 nm for obtaining maximum amplitude. The most favorable pulse shape is either ramp-up or triangular.
AB - Neural stimulation with infrared radiation has been explored for brain tissue, peripheral nerves, and cranial nerves including the auditory nerve. Initial experiments were conducted at wavelengths between λ = 1850 and λ = 2140 nm and the radiant energy was delivered with square pulses. Water absorption of the infrared radiation at λ = 1860 nm is similar to absorption at wavelengths between λ = 1310 and λ = 1600 nm, which are in the radiation wavelength range used for the communication industry. Technology for those wavelengths has already been developed and miniaturized and is readily available. The possibility of the infrared light to evoke compound action potentials (CAP) in the cochlea at λ = 1,375, λ = 1,460, and λ = 1550 nm was explored and compared to that of λ = 1860 nm in guinea pigs. Furthermore, rise and fall times of the 100 μs long pulses were changed and four basic pulse shapes (square, triangular, ramp-up, and ramp-down) were explored in their ability to evoke a CAP. In animals with pure tone threshold averages (PTAs) above 70 dB SPL, the results show that the favorable wavelength is λ = 1460 nm to reach threshold for stimulation and λ = 1375 nm or λ = 1460 nm for obtaining maximum amplitude. The most favorable pulse shape is either ramp-up or triangular.
KW - Cochlea
KW - Infrared
KW - LASER
KW - Neural stimulation
KW - Pulse shape
KW - Wavelength
UR - http://www.scopus.com/inward/record.url?scp=85099288928&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85099288928&partnerID=8YFLogxK
U2 - 10.1016/j.pbiomolbio.2020.12.004
DO - 10.1016/j.pbiomolbio.2020.12.004
M3 - Article
C2 - 33359901
AN - SCOPUS:85099288928
VL - 162
SP - 89
EP - 100
JO - Progress in Biophysics and Molecular Biology
JF - Progress in Biophysics and Molecular Biology
SN - 0079-6107
ER -