Optical stimulation of neural tissue in vivo

Abstract

For more than a century, the traditional method of stimulating neural activity has been based on electrical methods, and it remains the gold standard to date. We report a technological breakthrough in neural activation in which low-level, pulsed infrared laser light is used to elicit compound nerve and muscle potentials in mammalian peripheral nerve in vivo. Optically induced neural action potentials are spatially precise, artifact free, and damage free and are generated by use of energies well below tissue ablation threshold. Thus optical stimulation presents a simple yet novel approach to contact-free in vivo neural activation that has major implications for clinical neurosurgery, basic neurophysiology, and neuroscience.

Thermal Transients Excite Neurons through Universal Intramembrane Mechanoelectrical Effects

“…This study explored the effects of temperature changes on membrane capacitance and its associated currents in a joint attempt to clarify the experimental results of a key recent study [16] and to pave the way towards predictive modeling of INS [2][3][4][5][6][7][8][9][10][11][12][13][14][15] and other thermal neurostimulation techniques [18][19][20], which could potentially facilitate the development of more advanced and multimodal methods for neural circuit control. Another key motivation to pursue this problem came from our noting the very similar temperature-related capacitance rates of change observed in very different model systems [ Fig.…”

“…Both approaches also offer the long-term prospect of remotely affecting aberrant localized neural circuits that underlie many neurological diseases. A multitude of INS-related studies explored the ability of short-wave infrared (IR) pulses to stimulate neural structures including peripheral [3,4] and cranial nerves [5][6][7][8][9][10], retinal and cortical neurons [10][11][12], as well as cardiomyocytes [13,14]. It is stipulated that the INS phenomenon is mediated by temperature transients induced by IR absorption [15][16][17]; such transients can alternatively be induced using other forms of photoabsorption [18][19][20], or potentially by any other physical form of thermal neurostimulation that can be driven rapidly enough [21,22].…”

In Vivo Application of Optogenetics for Neural Circuit Analysis

“…62 Heat generated by light could also produce tissue damage, though the exact damage is hard to evaluate. For example, heat alone may influence neurons' responses, as demonstrated by pulsed infrared light stimulation 63 or possibly by pulsed ultrasound stimulation. 62,64 Most optogenetic studies use light Electrode data was hardware filtered using two data acquisition channels operating in parallel, yielding a low-frequency component ("field potential channel") and a high-frequency component ("spike channel").…”

Optical Control of Living Cells Electrical Activity by Conjugated Polymers

“…In these studies, the absorption of IR laser beams by water is usually used as a transduction mechanism. [23][24][25] With respect to Infrared Neural Stimulation, the CSPP mechanism has distinct advantages, especially for in-vitro experimentation. CSPP is based on light in the visible range and of moderate intensity, so that stimulation can be provided by the excitation path of a standard fluorescence microscope.…”